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DATE: July 24, 2026 at 08:00AM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Learning a new skill triggers both temporary cell swelling and lasting structural growth in the human brain
A new study published in PLoS Biology has found that learning a new motor skill sets off two different types of cellular changes in the human brain. The findings suggest that the brain experiences a temporary swelling of cell bodies followed by a long-lasting growth of cellular extensions in specific regions. This dual response offers a deeper understanding of how the human brain physically adapts when we learn something new.
Neuroplasticity refers to the brain’s ability to remodel its physical structure in response to new experiences. This biological process supports learning and memory, and it also influences a person’s vulnerability to neurological conditions.
Valeria Della-Maggiore, an associate professor at the National University of San Martin and the University of Buenos Aires, led the research. She also serves as an adjunct professor at McGill University and directs the Physiology of Action Lab.
“Structural plasticity, the brain’s ability to remodel its connections in response to experience, is fundamental to learning and memory and shapes development and degenerative disorders,” she told PsyPost. She explained that most human studies over the past two decades have used standard MRI protocols to detect changes in brain microstructure, assuming these changes were always plastic in nature.
“Yet animal studies show that cells may undergo structural changes that do not always reflect synapse remodeling,” Della-Maggiore said. “To disambiguate plastic from non-plastic processes, we combined ultra-high-gradient diffusion MRI with SANDI, a biophysical model that allows making inferences at the level of cellular compartments, that is, cell bodies and cell processes.”
To measure structural changes in humans, scientists have typically relied on a brain scanning technique called diffusion tensor imaging, or DTI. This method measures how water molecules move and diffuse through brain tissue. By tracking this water movement, scientists can infer changes in the brain’s microscopic structure.
DTI blends the signals from various parts of the brain tissue together. “DTI captures a single, global signal: it can tell you that a change in one region lasts longer than in another, but not what underlies it,” Della-Maggiore said. Because of this blending, the technique cannot easily distinguish between a permanent structural change and a temporary biological reaction.
To address this limitation, the authors utilized highly sensitive magnetic resonance imaging paired with the specialized mathematical model called Soma and Neurite Density Imaging, or SANDI. Rather than grouping all tissue signals together, SANDI separates the scanning signals into three distinct categories. These categories include the cell bodies, the cellular extensions called neurites, and the extracellular fluid surrounding the cells.
“This study was only possible through a genuinely multidisciplinary effort, in which neuroscientists, experts in diffusion MRI, mathematicians and modeling specialists, and engineers worked together around a single scientific question,” Della-Maggiore said.
The collaboration included her lab along with the Athinoula A. Martinos Center for Biomedical Imaging at Massachusetts General Hospital, and the Cardiff University Brain Research Imaging Centre. “Bringing these different forms of expertise into alignment is what made it possible to extract biological insight from a non-invasive measurement, something no single discipline could have achieved on its own,” she added.
The study included 29 healthy adults between the ages of 18 and 36, consisting of 16 females and 13 males. All participants were right-handed and reported no history of neurological or psychiatric conditions. They completed a motor sequence learning task involving typing a specific five-number sequence on a keyboard using the four fingers of their left, non-dominant hand. The exact sequence was 4-1-3-2-4, with the number 4 representing the index finger and the number 1 representing the pinky finger.
Participants were instructed to type the sequence as quickly and accurately as possible. They completed 15 practice blocks of this finger-tapping sequence. Each block consisted of 12 sequences and was separated by 25 seconds of rest. The entire training session took about 15 to 20 minutes.
To assess how well the participants retained the skill overnight, they were asked to complete eight additional practice blocks 24 hours later. To track brain activity and physical changes, the scientists used an ultra-high-gradient MRI scanner, which offers exceptional sensitivity for capturing microscopic tissue details. They collected functional MRI scans to measure active brain regions during the task. They also collected advanced diffusion MRI scans at three specific points: before the practice session began, 30 minutes after the practice ended, and 24 hours later.
The behavioral data showed that participants improved their typing speed and accuracy primarily during the short rest periods between practice blocks. The functional brain scans aligned with this observation, revealing increased activity in the brain’s memory and motor regions during these brief breaks. However, the most specific discoveries emerged from the SANDI model used to track cellular changes.
“When you learn a new skill, two processes of different spatial and temporal dynamics take place in your brain at the cellular level,” Della-Maggiore said. “One is transient and occurs at the level of cell bodies, which increase in size across all brain regions engaged by the task. The other is persistent, confined to the regions specifically involved in learning, and occurs at the level of cell processes, compatible with structural plasticity.”
The researchers found that DTI scans alone missed a layer of detail. “Our approach revealed something DTI cannot see, that the regions showing lasting changes also carry a transient response,” Della-Maggiore explained. “In other words, beneath what DTI reads as a single persistent effect, there are in fact two distinct processes unfolding on different timescales.”
Specifically, the researchers found a temporary increase in the apparent density of cell bodies across all the brain areas engaged by the task. These areas included the hippocampus, the primary motor cortex, the posterior parietal cortex, and the precuneus. This physical change was observed 30 minutes after the practice session. By the 24-hour mark, the cell bodies in these regions had returned to their normal baseline size.
“The second [surprise] was the spatial pattern: a transient change at the level of the cell body appeared uniformly across all regions engaged by learning, whereas the sustained change in cellular processes was confined to those regions specific to the learned skill,” Della-Maggiore said. “It was this dissociation, in both space and time, that let us infer different biological processes underlying these responses: a homeostatic process such as swelling of cell bodies induced by increased neuronal activity, and cell-process remodeling mediating genuine structural plasticity.”
The authors propose that this short-lived cell expansion is a temporary biological reaction to balance out intense cellular activity. When brain cells are highly active, they experience an imbalance of ions. To correct this imbalance, water flows into the cells, causing them to temporarily swell.
In addition to the temporary swelling, the SANDI model revealed a second, longer-lasting change in specific areas of the brain. The researchers observed a sustained increase in the density of cellular extensions in the precuneus and the posterior parietal cortex. These cellular extensions include structures like dendrites and axons, which connect different brain cells to one another.
This increase in cellular extensions persisted a full day after the learning task. The researchers noticed a direct link to task performance. “Notably, the more a person improved, the stronger this second change was,” Della-Maggiore said.
Interestingly, this long-lasting structural remodeling did not occur in the hippocampus. The hippocampus is a brain region known for helping encode new memories early in the learning process. The findings suggest that while the hippocampus is engaged initially, the long-term structural changes required to retain a motor skill happen in the outer layers of the brain, known as the cortex.
“The broader message is that a change in brain structure is not, in itself, evidence of learning-related plasticity,” Della-Maggiore said. “Being able to separate these processes in a living brain, non-invasively, provides something that did not exist before in human neuroscience: a mechanistic window onto brain plasticity, allowing us to begin inferring biological mechanisms directly in humans rather than relying on animal models.”
Interpreting these findings requires acknowledging a few limitations related to the scanning technology. The SANDI model estimates relative signal fractions of cell components rather than providing a direct physical measurement of cellular volume. The technique relies on specific mathematical assumptions about how water moves in the brain.
“Our approach does not quantify cells or cell processes directly,” Della-Maggiore explained. “It infers how much different cellular components contribute to the MRI signal, based on a biophysical model whose interpretation is grounded in animal and histological evidence.”
She added that referring to changes in cell bodies or cell processes involves principled inferences, not microscopic observations. “The strength of the method lies in tracking how these signals evolve over time, compared against the person’s own baseline,” she said.
The study focused on a specific finger-tapping task in a small group of healthy young adults. Different types of learning, such as studying a new language or solving complex math problems, might engage different cellular mechanisms. “Our broader aim is to keep refining this approach to probe the biological mechanisms of plasticity in ever greater detail, directly in humans,” Della-Maggiore said.
The researchers hope to apply this multi-compartment imaging approach to other areas of neuroscience. “Beyond learning, distinguishing genuine, adaptive remodeling from other processes could prove valuable in contexts such as development, aging, and disease, including conditions like neurodegeneration or neuroinflammation, where telling apart healthy from harmful structural change is both difficult and clinically important,” she said.
“The results move the field beyond descriptive diffusion changes toward mechanistic inference, which is particularly valuable for studies of learning, development, and disease,” Della-Maggiore concluded.
The study, “Learning engages transient and sustained cellular mechanisms in the human brain,” was authored by Guillermina Griffa, Marco Palombo, Abraham Yeffal, Hong-Hsi Lee, Agustin Solano, Susie Y. Huang, and Valeria Della-Maggiore.
-------------------------------------------------
Private, vetted email list for mental health professionals: https://www.clinicians-exchange.org
Unofficial Psychology Today Xitter to toot feed at Psych Today Unofficial Bot @PTUnofficialBot
-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #BrainPlasticity #Neurobiology #LearningAndMemory #Neuroimaging #SANDI #DTI #MotorSkillLearning #DiffusionMRI #Hippocampus #Cortex
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DATE: July 24, 2026 at 08:00AM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Learning a new skill triggers both temporary cell swelling and lasting structural growth in the human brain
A new study published in PLoS Biology has found that learning a new motor skill sets off two different types of cellular changes in the human brain. The findings suggest that the brain experiences a temporary swelling of cell bodies followed by a long-lasting growth of cellular extensions in specific regions. This dual response offers a deeper understanding of how the human brain physically adapts when we learn something new.
Neuroplasticity refers to the brain’s ability to remodel its physical structure in response to new experiences. This biological process supports learning and memory, and it also influences a person’s vulnerability to neurological conditions.
Valeria Della-Maggiore, an associate professor at the National University of San Martin and the University of Buenos Aires, led the research. She also serves as an adjunct professor at McGill University and directs the Physiology of Action Lab.
“Structural plasticity, the brain’s ability to remodel its connections in response to experience, is fundamental to learning and memory and shapes development and degenerative disorders,” she told PsyPost. She explained that most human studies over the past two decades have used standard MRI protocols to detect changes in brain microstructure, assuming these changes were always plastic in nature.
“Yet animal studies show that cells may undergo structural changes that do not always reflect synapse remodeling,” Della-Maggiore said. “To disambiguate plastic from non-plastic processes, we combined ultra-high-gradient diffusion MRI with SANDI, a biophysical model that allows making inferences at the level of cellular compartments, that is, cell bodies and cell processes.”
To measure structural changes in humans, scientists have typically relied on a brain scanning technique called diffusion tensor imaging, or DTI. This method measures how water molecules move and diffuse through brain tissue. By tracking this water movement, scientists can infer changes in the brain’s microscopic structure.
DTI blends the signals from various parts of the brain tissue together. “DTI captures a single, global signal: it can tell you that a change in one region lasts longer than in another, but not what underlies it,” Della-Maggiore said. Because of this blending, the technique cannot easily distinguish between a permanent structural change and a temporary biological reaction.
To address this limitation, the authors utilized highly sensitive magnetic resonance imaging paired with the specialized mathematical model called Soma and Neurite Density Imaging, or SANDI. Rather than grouping all tissue signals together, SANDI separates the scanning signals into three distinct categories. These categories include the cell bodies, the cellular extensions called neurites, and the extracellular fluid surrounding the cells.
“This study was only possible through a genuinely multidisciplinary effort, in which neuroscientists, experts in diffusion MRI, mathematicians and modeling specialists, and engineers worked together around a single scientific question,” Della-Maggiore said.
The collaboration included her lab along with the Athinoula A. Martinos Center for Biomedical Imaging at Massachusetts General Hospital, and the Cardiff University Brain Research Imaging Centre. “Bringing these different forms of expertise into alignment is what made it possible to extract biological insight from a non-invasive measurement, something no single discipline could have achieved on its own,” she added.
The study included 29 healthy adults between the ages of 18 and 36, consisting of 16 females and 13 males. All participants were right-handed and reported no history of neurological or psychiatric conditions. They completed a motor sequence learning task involving typing a specific five-number sequence on a keyboard using the four fingers of their left, non-dominant hand. The exact sequence was 4-1-3-2-4, with the number 4 representing the index finger and the number 1 representing the pinky finger.
Participants were instructed to type the sequence as quickly and accurately as possible. They completed 15 practice blocks of this finger-tapping sequence. Each block consisted of 12 sequences and was separated by 25 seconds of rest. The entire training session took about 15 to 20 minutes.
To assess how well the participants retained the skill overnight, they were asked to complete eight additional practice blocks 24 hours later. To track brain activity and physical changes, the scientists used an ultra-high-gradient MRI scanner, which offers exceptional sensitivity for capturing microscopic tissue details. They collected functional MRI scans to measure active brain regions during the task. They also collected advanced diffusion MRI scans at three specific points: before the practice session began, 30 minutes after the practice ended, and 24 hours later.
The behavioral data showed that participants improved their typing speed and accuracy primarily during the short rest periods between practice blocks. The functional brain scans aligned with this observation, revealing increased activity in the brain’s memory and motor regions during these brief breaks. However, the most specific discoveries emerged from the SANDI model used to track cellular changes.
“When you learn a new skill, two processes of different spatial and temporal dynamics take place in your brain at the cellular level,” Della-Maggiore said. “One is transient and occurs at the level of cell bodies, which increase in size across all brain regions engaged by the task. The other is persistent, confined to the regions specifically involved in learning, and occurs at the level of cell processes, compatible with structural plasticity.”
The researchers found that DTI scans alone missed a layer of detail. “Our approach revealed something DTI cannot see, that the regions showing lasting changes also carry a transient response,” Della-Maggiore explained. “In other words, beneath what DTI reads as a single persistent effect, there are in fact two distinct processes unfolding on different timescales.”
Specifically, the researchers found a temporary increase in the apparent density of cell bodies across all the brain areas engaged by the task. These areas included the hippocampus, the primary motor cortex, the posterior parietal cortex, and the precuneus. This physical change was observed 30 minutes after the practice session. By the 24-hour mark, the cell bodies in these regions had returned to their normal baseline size.
“The second [surprise] was the spatial pattern: a transient change at the level of the cell body appeared uniformly across all regions engaged by learning, whereas the sustained change in cellular processes was confined to those regions specific to the learned skill,” Della-Maggiore said. “It was this dissociation, in both space and time, that let us infer different biological processes underlying these responses: a homeostatic process such as swelling of cell bodies induced by increased neuronal activity, and cell-process remodeling mediating genuine structural plasticity.”
The authors propose that this short-lived cell expansion is a temporary biological reaction to balance out intense cellular activity. When brain cells are highly active, they experience an imbalance of ions. To correct this imbalance, water flows into the cells, causing them to temporarily swell.
In addition to the temporary swelling, the SANDI model revealed a second, longer-lasting change in specific areas of the brain. The researchers observed a sustained increase in the density of cellular extensions in the precuneus and the posterior parietal cortex. These cellular extensions include structures like dendrites and axons, which connect different brain cells to one another.
This increase in cellular extensions persisted a full day after the learning task. The researchers noticed a direct link to task performance. “Notably, the more a person improved, the stronger this second change was,” Della-Maggiore said.
Interestingly, this long-lasting structural remodeling did not occur in the hippocampus. The hippocampus is a brain region known for helping encode new memories early in the learning process. The findings suggest that while the hippocampus is engaged initially, the long-term structural changes required to retain a motor skill happen in the outer layers of the brain, known as the cortex.
“The broader message is that a change in brain structure is not, in itself, evidence of learning-related plasticity,” Della-Maggiore said. “Being able to separate these processes in a living brain, non-invasively, provides something that did not exist before in human neuroscience: a mechanistic window onto brain plasticity, allowing us to begin inferring biological mechanisms directly in humans rather than relying on animal models.”
Interpreting these findings requires acknowledging a few limitations related to the scanning technology. The SANDI model estimates relative signal fractions of cell components rather than providing a direct physical measurement of cellular volume. The technique relies on specific mathematical assumptions about how water moves in the brain.
“Our approach does not quantify cells or cell processes directly,” Della-Maggiore explained. “It infers how much different cellular components contribute to the MRI signal, based on a biophysical model whose interpretation is grounded in animal and histological evidence.”
She added that referring to changes in cell bodies or cell processes involves principled inferences, not microscopic observations. “The strength of the method lies in tracking how these signals evolve over time, compared against the person’s own baseline,” she said.
The study focused on a specific finger-tapping task in a small group of healthy young adults. Different types of learning, such as studying a new language or solving complex math problems, might engage different cellular mechanisms. “Our broader aim is to keep refining this approach to probe the biological mechanisms of plasticity in ever greater detail, directly in humans,” Della-Maggiore said.
The researchers hope to apply this multi-compartment imaging approach to other areas of neuroscience. “Beyond learning, distinguishing genuine, adaptive remodeling from other processes could prove valuable in contexts such as development, aging, and disease, including conditions like neurodegeneration or neuroinflammation, where telling apart healthy from harmful structural change is both difficult and clinically important,” she said.
“The results move the field beyond descriptive diffusion changes toward mechanistic inference, which is particularly valuable for studies of learning, development, and disease,” Della-Maggiore concluded.
The study, “Learning engages transient and sustained cellular mechanisms in the human brain,” was authored by Guillermina Griffa, Marco Palombo, Abraham Yeffal, Hong-Hsi Lee, Agustin Solano, Susie Y. Huang, and Valeria Della-Maggiore.
-------------------------------------------------
Private, vetted email list for mental health professionals: https://www.clinicians-exchange.org
Unofficial Psychology Today Xitter to toot feed at Psych Today Unofficial Bot @PTUnofficialBot
-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #BrainPlasticity #Neurobiology #LearningAndMemory #Neuroimaging #SANDI #DTI #MotorSkillLearning #DiffusionMRI #Hippocampus #Cortex
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DATE: July 22, 2026 at 08:00PM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Tiny vesicles in breast milk carry stress signals to the infant brain
URL: https://www.psypost.org/enriched-environments-protect-infant-brains-from-maternal-immune-stress/
When a parent experiences an infection while breastfeeding, their body can pass biological stress signals to the newborn through tiny particles hidden in the milk. A recent study reveals that modifying the parent’s environment to be more engaging and supportive can block these stress signals, protecting the infant’s developing brain and future behavior. The research was published in the journal Molecular Psychiatry.
Breast milk provides more than simple calories and basic nutrition. It contains a massive variety of hormones, immune cells, and microscopic bubbles called extracellular vesicles. These tiny, membrane-bound packages operate like biological mail carriers. They travel safely through the harsh environment of the infant gut, enter the bloodstream, and drop off genetic material in distant tissues.
Inside these vesicles are regulatory molecules known as microRNAs. To understand microRNAs, it helps to look at how cells normally function. Your DNA acts as a master instruction manual, filled with blueprints for keeping the body alive. When a cell needs to function, it creates messenger RNA to carry those instructions to the cellular factories that build proteins.
MicroRNAs are small pieces of genetic code that act like a dimmer switch, attaching to the messenger RNA and stopping it from building proteins. Because they pause the construction phase, this process is known as post-transcriptional regulation. By delivering these microRNAs to an infant, milk vesicles can turn specific cellular functions on or off in the developing body.
Scientists understand that maternal illness during pregnancy can alter fetal brain development. Less is known about how infections during the postnatal nursing period might change the genetic messages passed through milk. Julia Martz of the Massachusetts College of Pharmacy and Health Sciences, Baila Hammer of Touro University, and a team of colleagues set out to investigate this dynamic.
The researchers wanted to see if an immune challenge in a lactating parent alters milk composition enough to change the trajectory of an infant’s brain. They also wanted to know if a better living environment could buffer the mother and infant against these biological changes. To test this, the researchers divided lactating rats into two different living conditions. Half the animals lived in standard, plain laboratory cages, while the other half lived in enriched environments featuring extra space, climbing structures, and toys.
On the tenth day of nursing their pups, half the mothers in each housing group received an injection of a bacterial component known as lipopolysaccharide. This component is derived from Escherichia coli bacteria. It does not cause a real infection, but it tricks the body into sensing an invader, prompting temporary inflammation and mild sickness behaviors like lethargy. Researchers often use this substance because it creates a predictable, uniform immune response without the chaotic variables of a live, replicating pathogen.
The remaining mothers received a harmless saline placebo injection. Two hours later, researchers collected milk from all the experimental groups. They used a high-speed centrifuge to isolate the extracellular vesicles from the milk and sequence the genetic cargo hidden inside.
The researchers found that simulated infections heavily altered the composition of the milk. Not only did the fat content of the milk drop, but the levels of a stress hormone called corticosterone increased. Beyond basic nutrition, the immune challenge also changed the profile of the microRNAs packaged into the milk vesicles.
This effect was mostly seen in the mothers housed in standard cages. For these mothers, the immune challenge resulted in dozens of altered microRNAs compared to the healthy control group. The enriched environment provided a strong protective effect against this outcome. Sick mothers living in the complex environments saw a much less drastic shift in their milk’s genetic cargo, and their milk’s fat content remained normal.
The researchers then looked at the brains of the nursing pups, focusing specifically on the hippocampus. The hippocampus is a brain structure located deep within the temporal lobe, and it heavily regulates learning, memory, and emotional processing. Like the milk vesicles, the pups nursing from sick, standard-housed mothers showed altered microRNA profiles in their hippocampus.
In many cases, the specific microRNAs altered in the infant brain matched the ones found in the mothers’ milk. This overlap suggests that the milk vesicles may reach the brain to deposit their instructions, or at least trigger a chain reaction that shifts the infant’s brain chemistry. Just like the milk samples, pups nursing from enriched-housed mothers largely avoided these widespread genetic changes.
This genetic shift had lasting behavioral consequences for the developing animals. When the pups grew into adulthood, they underwent behavioral testing. One test involved placing the rats in an open, brightly lit arena to measure anxiety. Animals that feel anxious tend to hug the walls, while more relaxed animals will freely explore the exposed center.
A second test evaluated how much the animals preferred interacting with a new, unfamiliar rat versus an inanimate object. This kind of social preference test helps researchers measure sociability and developmental milestones in rodents. The adult offspring of sick, standard-housed mothers showed higher levels of anxiety-like behaviors in the open arena, and they also exhibited a reduced preference for socializing with other rats.
The enriched living spaces entirely prevented these adult behavioral changes. Even though the mothers in the enriched cages experienced the exact same immune challenge, their adult offspring behaved just like the healthy control groups. The researchers also noted that maternal stress hormones could not explain this behavioral rescue. Milk corticosterone levels remained high even in the enriched mothers, meaning the protected vesicle cargo was a more likely source of the behavioral buffer.
The researchers noted that this was a small study, utilizing seven or eight litters per testing condition, for a total of about thirty litters. This sample size carries a few inherent limitations. Milk composition changes constantly across the natural nursing timeline of any mammal, adapting to the growing infant’s daily needs. Because this experiment only sampled milk over a narrow two-day window in the middle of the lactation phase, it remains unknown how early or late stages of nursing might respond to immune stress.
Another limitation involves the exact physical pathway of the genetic cargo. While the researchers found matching microRNAs in the milk and the infant brains, they did not visually trace the physical journey of the vesicles. It is entirely possible the milk vesicles act indirectly in the body. For instance, the vesicles might alter the infant’s gut bacteria, which in turn send signals that influence the hippocampus.
Future studies will need to use fluorescent markers to track exactly where these maternal vesicles travel inside the offspring. Other components of the milk, such as structural fats and immune proteins, might also work alongside the microRNAs to shape infant brain development. Isolating these microscopic variables takes immense resources and time.
Despite these open questions, the findings suggest a very physical link between a caregiver’s environment and the biological quality of their care. Supporting nursing parents with better environmental conditions and reduced daily stress might do more than just improve their mood. It could directly shape the genetic instructions passed on to the next generation, building a more resilient infant brain.
The study, “Investigating milk-derived extracellular vesicles as mediators of maternal stress and environmental intervention,” was authored by Julia Martz, Baila Hammer, Tristen J. Langen, Benjamin N. Berkowitz, Benzion Berkowitz, Jasmyne A. Storm, Jueqin Lu, Deepali Lehri, Sanoji Wijenayake, Jordan Marrocco, and Amanda C. Kentner.
URL: https://www.psypost.org/enriched-environments-protect-infant-brains-from-maternal-immune-stress/
-------------------------------------------------
Private, vetted email list for mental health professionals: https://www.clinicians-exchange.org
Unofficial Psychology Today Xitter to toot feed at Psych Today Unofficial Bot @PTUnofficialBot
-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #milkvesicles #extracellularvesicles #microRNAs #breastmilkbiology #maternalstress #infantbraindevelopment #hippocampus #enrichedenvironment #protectivecare #neuroscienceresearch
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DATE: July 22, 2026 at 08:00PM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Tiny vesicles in breast milk carry stress signals to the infant brain
URL: https://www.psypost.org/enriched-environments-protect-infant-brains-from-maternal-immune-stress/
When a parent experiences an infection while breastfeeding, their body can pass biological stress signals to the newborn through tiny particles hidden in the milk. A recent study reveals that modifying the parent’s environment to be more engaging and supportive can block these stress signals, protecting the infant’s developing brain and future behavior. The research was published in the journal Molecular Psychiatry.
Breast milk provides more than simple calories and basic nutrition. It contains a massive variety of hormones, immune cells, and microscopic bubbles called extracellular vesicles. These tiny, membrane-bound packages operate like biological mail carriers. They travel safely through the harsh environment of the infant gut, enter the bloodstream, and drop off genetic material in distant tissues.
Inside these vesicles are regulatory molecules known as microRNAs. To understand microRNAs, it helps to look at how cells normally function. Your DNA acts as a master instruction manual, filled with blueprints for keeping the body alive. When a cell needs to function, it creates messenger RNA to carry those instructions to the cellular factories that build proteins.
MicroRNAs are small pieces of genetic code that act like a dimmer switch, attaching to the messenger RNA and stopping it from building proteins. Because they pause the construction phase, this process is known as post-transcriptional regulation. By delivering these microRNAs to an infant, milk vesicles can turn specific cellular functions on or off in the developing body.
Scientists understand that maternal illness during pregnancy can alter fetal brain development. Less is known about how infections during the postnatal nursing period might change the genetic messages passed through milk. Julia Martz of the Massachusetts College of Pharmacy and Health Sciences, Baila Hammer of Touro University, and a team of colleagues set out to investigate this dynamic.
The researchers wanted to see if an immune challenge in a lactating parent alters milk composition enough to change the trajectory of an infant’s brain. They also wanted to know if a better living environment could buffer the mother and infant against these biological changes. To test this, the researchers divided lactating rats into two different living conditions. Half the animals lived in standard, plain laboratory cages, while the other half lived in enriched environments featuring extra space, climbing structures, and toys.
On the tenth day of nursing their pups, half the mothers in each housing group received an injection of a bacterial component known as lipopolysaccharide. This component is derived from Escherichia coli bacteria. It does not cause a real infection, but it tricks the body into sensing an invader, prompting temporary inflammation and mild sickness behaviors like lethargy. Researchers often use this substance because it creates a predictable, uniform immune response without the chaotic variables of a live, replicating pathogen.
The remaining mothers received a harmless saline placebo injection. Two hours later, researchers collected milk from all the experimental groups. They used a high-speed centrifuge to isolate the extracellular vesicles from the milk and sequence the genetic cargo hidden inside.
The researchers found that simulated infections heavily altered the composition of the milk. Not only did the fat content of the milk drop, but the levels of a stress hormone called corticosterone increased. Beyond basic nutrition, the immune challenge also changed the profile of the microRNAs packaged into the milk vesicles.
This effect was mostly seen in the mothers housed in standard cages. For these mothers, the immune challenge resulted in dozens of altered microRNAs compared to the healthy control group. The enriched environment provided a strong protective effect against this outcome. Sick mothers living in the complex environments saw a much less drastic shift in their milk’s genetic cargo, and their milk’s fat content remained normal.
The researchers then looked at the brains of the nursing pups, focusing specifically on the hippocampus. The hippocampus is a brain structure located deep within the temporal lobe, and it heavily regulates learning, memory, and emotional processing. Like the milk vesicles, the pups nursing from sick, standard-housed mothers showed altered microRNA profiles in their hippocampus.
In many cases, the specific microRNAs altered in the infant brain matched the ones found in the mothers’ milk. This overlap suggests that the milk vesicles may reach the brain to deposit their instructions, or at least trigger a chain reaction that shifts the infant’s brain chemistry. Just like the milk samples, pups nursing from enriched-housed mothers largely avoided these widespread genetic changes.
This genetic shift had lasting behavioral consequences for the developing animals. When the pups grew into adulthood, they underwent behavioral testing. One test involved placing the rats in an open, brightly lit arena to measure anxiety. Animals that feel anxious tend to hug the walls, while more relaxed animals will freely explore the exposed center.
A second test evaluated how much the animals preferred interacting with a new, unfamiliar rat versus an inanimate object. This kind of social preference test helps researchers measure sociability and developmental milestones in rodents. The adult offspring of sick, standard-housed mothers showed higher levels of anxiety-like behaviors in the open arena, and they also exhibited a reduced preference for socializing with other rats.
The enriched living spaces entirely prevented these adult behavioral changes. Even though the mothers in the enriched cages experienced the exact same immune challenge, their adult offspring behaved just like the healthy control groups. The researchers also noted that maternal stress hormones could not explain this behavioral rescue. Milk corticosterone levels remained high even in the enriched mothers, meaning the protected vesicle cargo was a more likely source of the behavioral buffer.
The researchers noted that this was a small study, utilizing seven or eight litters per testing condition, for a total of about thirty litters. This sample size carries a few inherent limitations. Milk composition changes constantly across the natural nursing timeline of any mammal, adapting to the growing infant’s daily needs. Because this experiment only sampled milk over a narrow two-day window in the middle of the lactation phase, it remains unknown how early or late stages of nursing might respond to immune stress.
Another limitation involves the exact physical pathway of the genetic cargo. While the researchers found matching microRNAs in the milk and the infant brains, they did not visually trace the physical journey of the vesicles. It is entirely possible the milk vesicles act indirectly in the body. For instance, the vesicles might alter the infant’s gut bacteria, which in turn send signals that influence the hippocampus.
Future studies will need to use fluorescent markers to track exactly where these maternal vesicles travel inside the offspring. Other components of the milk, such as structural fats and immune proteins, might also work alongside the microRNAs to shape infant brain development. Isolating these microscopic variables takes immense resources and time.
Despite these open questions, the findings suggest a very physical link between a caregiver’s environment and the biological quality of their care. Supporting nursing parents with better environmental conditions and reduced daily stress might do more than just improve their mood. It could directly shape the genetic instructions passed on to the next generation, building a more resilient infant brain.
The study, “Investigating milk-derived extracellular vesicles as mediators of maternal stress and environmental intervention,” was authored by Julia Martz, Baila Hammer, Tristen J. Langen, Benjamin N. Berkowitz, Benzion Berkowitz, Jasmyne A. Storm, Jueqin Lu, Deepali Lehri, Sanoji Wijenayake, Jordan Marrocco, and Amanda C. Kentner.
URL: https://www.psypost.org/enriched-environments-protect-infant-brains-from-maternal-immune-stress/
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#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #milkvesicles #extracellularvesicles #microRNAs #breastmilkbiology #maternalstress #infantbraindevelopment #hippocampus #enrichedenvironment #protectivecare #neuroscienceresearch
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DATE: July 17, 2026 at 02:00PM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Brain structure variations are linked to different types of traumatic memories
New research reveals that the microstructural integrity of specific brain pathways is associated with how intensely a person experiences intrusive memories after a trauma. Published in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, the study suggests that distinct white matter connections correspond to different physical and emotional qualities of these recurring flashbacks.
Trauma-related intrusive memories are spontaneous and emotionally overwhelming sensory recollections. Individuals who experience them often feel as though the traumatic event is occurring in the present moment, blurring the line between past trauma and current reality. These intrusive flashbacks are a defining symptom of post-traumatic stress disorder, or PTSD, and they frequently dictate the overall severity of a person’s condition.
Despite the massive impact these intrusive memories have on quality of life, the precise neurobiological mechanisms that govern their unique properties remain poorly understood. Many people experience intrusive memories differently. Some might find that their memories are dominated by intense visual fragments, while others might feel an overwhelming sense of reliving the event physically and emotionally.
To develop better therapeutic interventions, scientists are attempting to understand the exact physical wiring in the brain that supports these varied experiences. Theoretical models propose that the sensory details of traumatic flashbacks stem from a disruption in the way different brain regions communicate.
The hippocampus, a seahorse-shaped region deep in the brain, is fundamentally responsible for forming and retrieving episodic memories. When a memory is recalled, the hippocampus usually communicates with posterior cortical systems. These outer layers of the brain are involved in processing sensory information, reconstructing mental scenes, and maintaining a person’s internal sense of self.
Steven J. Granger, a researcher at McLean Hospital and Harvard Medical School, led a team to investigate the structural pathways that bridge these distinct neural systems. The researchers hypothesized that the microscopic organization of these specific cellular pathways might explain why some people have trauma memories characterized primarily by sudden intrusiveness, while others experience memories defined by a profound sense of reliving the event.
The human brain relies on white matter to facilitate this complex communication. White matter tissue acts as a biological scaffolding, built from insulated nerve fibers called axons that bundle together to connect disparate brain regions. These pathways dictate which parts of the brain can interact, controlling the speed and efficiency with which electrical signals travel.
Prior functional brain imaging indicated that the subjective qualities of intrusive memories tend to correspond with how frequently the hippocampus activates alongside other brain networks. Still, the physical structure supporting these functional networks had not yet been evaluated in relation to the everyday experience of traumatic memories.
To capture the true nature of traumatic memories as they happen, Granger and his colleagues recruited 114 adults who had survived a traumatic event. These participants were experiencing regular intrusive memories, and a majority met the criteria for a formal PTSD diagnosis.
Most laboratory studies of trauma rely on asking patients to voluntarily recall their distressing experiences in a clinical setting. To avoid this artificial environment, the research team used a smartphone application to administer periodic surveys to the participants over the course of two weeks.
This technique, known as ecological momentary assessment, allowed the team to track spontaneous memories as they struck in the real world. Several times a day, participants received prompts to report if an intrusive memory had occurred since their last check-in. If they said yes, they immediately rated the memory’s vividness, visual detail, emotional intensity, intrusiveness, and the degree to which they felt they were actively reliving the event.
After the two-week reporting period, the participants underwent a specialized type of magnetic resonance imaging. The researchers used a technique called diffusion-weighted imaging, which tracks the tiny movements of water molecules within brain tissue. Because water diffuses differently alongside cellular barriers, mapping this movement allows scientists to visualize the direction and density of white matter fibers.
Using this imaging data, the researchers calculated a metric called fractional anisotropy. This metric serves as an index of white matter microstructural integrity, essentially measuring how organized and tightly bundled the nerve fibers are within a specific pathway.
The team focused their analysis on two separate white matter pathways that connect the hippocampus to the back of the brain. The first target was the parahippocampal-parietal cingulum, a localized branch of nerve fibers linking the memory center to regions involved in mental imagery and the integration of internal thoughts.
The second target was the inferior longitudinal fasciculus. This thick band of white matter provides a direct communication route between the brain’s temporal memory areas and the visual cortex, which processes sights.
The researchers analyzed their brain scans alongside the thousands of real-world smartphone survey responses. To ensure their mathematical models were as accurate as possible, they incorporated information from their previous functional imaging studies, a statistical approach that anchors new structural data to known patterns of biological activity.
They found that the microscopic integrity of the two separate pathways corresponded to entirely different features of the trauma memories. Specifically, they discovered that a lower level of structural integrity in the parahippocampal-parietal cingulum was associated with a higher degree of memory intrusiveness.
To confirm that this association was unique to the examined memory pathway, the researchers also tested a control tract in the frontal lobe of the brain. They found no relationship between the frontal pathway and memory intrusiveness, supporting their hypothesis that the specific connection between the hippocampus and the parietal cortex plays a distinct role in managing unwanted thoughts.
This particular brain bundle projects to posterior regions that help govern memory suppression and the allocation of attention. If the structural integrity of this pathway is degraded, the brain might have a compromised ability to suppress unwanted memories, opening the door for the spontaneous and unprompted intrusions that define traumatic flashbacks.
In contrast, the researchers found that lower microstructural organization in the inferior longitudinal fasciculus was linked to a stronger sense of reliving the trauma in the present moment. This associative pathway connects memory areas to the visual cortex, playing a unique role in integrating incoming visual signals with emotional information.
When this secondary pathway is compromised, individuals might experience a failure to separate internal traumatic memories from their current visual reality. This biological blurring of boundaries could contribute to the overwhelming sensation that makes severe trauma memories so disorienting.
Because the research team conducted their brain imaging at a single point in time, the study cannot definitively determine the directionality of these relationships. It remains entirely unknown whether a natural variation in white matter integrity serves as a preexisting vulnerability that predisposes a person to intense traumatic memories after an event occurs.
Alternatively, the structural differences observed in the scans could be a biological consequence of repeatedly experiencing severe intrusive thoughts over time. The constant, repetitive retrieval of highly charged traumatic memories might physically alter the brain’s white matter pathways, similar to how repeated use changes a physical path through a forest.
Future research will require scientists to image trauma survivors repeatedly during the early aftermath of a distressing event, tracking how both the brain structure and the psychological symptoms evolve over several months or years. Additional studies involving controlled laboratory recall and naturalistic tracking in the exact same individuals could also clarify the biological overlap between voluntary and involuntary memories.
Through integrating the real-world tracking of memory experiences with advanced mapping of anatomical brain connections, researchers are gaining a deeper understanding of PTSD. Eventually, translating these physical variations into clinical profiles could help doctors pinpoint specific neural circuits, opening the door for treatments that target the specific memory symptoms a patient struggles with most.
The study, “Microstructural Integrity of Hippocampal–Posterior Cortical White Matter Is Associated With Phenomenological Properties of Trauma-Related Intrusive Memories,” was authored by Steven J. Granger, Boyu Ren, Kevin J. Clancy, Yara Pollmann, Justin T. Baker, and Isabelle M. Rosso.
-------------------------------------------------
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-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #TraumaMemories #PTSDResearch #Hippocampus #WhiteMatter #Neuroimaging #DiffusionTensorImaging #IntrusiveMemories #MemoryReliving #BrainStructure #MentalHealthScience
-
DATE: July 17, 2026 at 02:00PM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Brain structure variations are linked to different types of traumatic memories
New research reveals that the microstructural integrity of specific brain pathways is associated with how intensely a person experiences intrusive memories after a trauma. Published in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, the study suggests that distinct white matter connections correspond to different physical and emotional qualities of these recurring flashbacks.
Trauma-related intrusive memories are spontaneous and emotionally overwhelming sensory recollections. Individuals who experience them often feel as though the traumatic event is occurring in the present moment, blurring the line between past trauma and current reality. These intrusive flashbacks are a defining symptom of post-traumatic stress disorder, or PTSD, and they frequently dictate the overall severity of a person’s condition.
Despite the massive impact these intrusive memories have on quality of life, the precise neurobiological mechanisms that govern their unique properties remain poorly understood. Many people experience intrusive memories differently. Some might find that their memories are dominated by intense visual fragments, while others might feel an overwhelming sense of reliving the event physically and emotionally.
To develop better therapeutic interventions, scientists are attempting to understand the exact physical wiring in the brain that supports these varied experiences. Theoretical models propose that the sensory details of traumatic flashbacks stem from a disruption in the way different brain regions communicate.
The hippocampus, a seahorse-shaped region deep in the brain, is fundamentally responsible for forming and retrieving episodic memories. When a memory is recalled, the hippocampus usually communicates with posterior cortical systems. These outer layers of the brain are involved in processing sensory information, reconstructing mental scenes, and maintaining a person’s internal sense of self.
Steven J. Granger, a researcher at McLean Hospital and Harvard Medical School, led a team to investigate the structural pathways that bridge these distinct neural systems. The researchers hypothesized that the microscopic organization of these specific cellular pathways might explain why some people have trauma memories characterized primarily by sudden intrusiveness, while others experience memories defined by a profound sense of reliving the event.
The human brain relies on white matter to facilitate this complex communication. White matter tissue acts as a biological scaffolding, built from insulated nerve fibers called axons that bundle together to connect disparate brain regions. These pathways dictate which parts of the brain can interact, controlling the speed and efficiency with which electrical signals travel.
Prior functional brain imaging indicated that the subjective qualities of intrusive memories tend to correspond with how frequently the hippocampus activates alongside other brain networks. Still, the physical structure supporting these functional networks had not yet been evaluated in relation to the everyday experience of traumatic memories.
To capture the true nature of traumatic memories as they happen, Granger and his colleagues recruited 114 adults who had survived a traumatic event. These participants were experiencing regular intrusive memories, and a majority met the criteria for a formal PTSD diagnosis.
Most laboratory studies of trauma rely on asking patients to voluntarily recall their distressing experiences in a clinical setting. To avoid this artificial environment, the research team used a smartphone application to administer periodic surveys to the participants over the course of two weeks.
This technique, known as ecological momentary assessment, allowed the team to track spontaneous memories as they struck in the real world. Several times a day, participants received prompts to report if an intrusive memory had occurred since their last check-in. If they said yes, they immediately rated the memory’s vividness, visual detail, emotional intensity, intrusiveness, and the degree to which they felt they were actively reliving the event.
After the two-week reporting period, the participants underwent a specialized type of magnetic resonance imaging. The researchers used a technique called diffusion-weighted imaging, which tracks the tiny movements of water molecules within brain tissue. Because water diffuses differently alongside cellular barriers, mapping this movement allows scientists to visualize the direction and density of white matter fibers.
Using this imaging data, the researchers calculated a metric called fractional anisotropy. This metric serves as an index of white matter microstructural integrity, essentially measuring how organized and tightly bundled the nerve fibers are within a specific pathway.
The team focused their analysis on two separate white matter pathways that connect the hippocampus to the back of the brain. The first target was the parahippocampal-parietal cingulum, a localized branch of nerve fibers linking the memory center to regions involved in mental imagery and the integration of internal thoughts.
The second target was the inferior longitudinal fasciculus. This thick band of white matter provides a direct communication route between the brain’s temporal memory areas and the visual cortex, which processes sights.
The researchers analyzed their brain scans alongside the thousands of real-world smartphone survey responses. To ensure their mathematical models were as accurate as possible, they incorporated information from their previous functional imaging studies, a statistical approach that anchors new structural data to known patterns of biological activity.
They found that the microscopic integrity of the two separate pathways corresponded to entirely different features of the trauma memories. Specifically, they discovered that a lower level of structural integrity in the parahippocampal-parietal cingulum was associated with a higher degree of memory intrusiveness.
To confirm that this association was unique to the examined memory pathway, the researchers also tested a control tract in the frontal lobe of the brain. They found no relationship between the frontal pathway and memory intrusiveness, supporting their hypothesis that the specific connection between the hippocampus and the parietal cortex plays a distinct role in managing unwanted thoughts.
This particular brain bundle projects to posterior regions that help govern memory suppression and the allocation of attention. If the structural integrity of this pathway is degraded, the brain might have a compromised ability to suppress unwanted memories, opening the door for the spontaneous and unprompted intrusions that define traumatic flashbacks.
In contrast, the researchers found that lower microstructural organization in the inferior longitudinal fasciculus was linked to a stronger sense of reliving the trauma in the present moment. This associative pathway connects memory areas to the visual cortex, playing a unique role in integrating incoming visual signals with emotional information.
When this secondary pathway is compromised, individuals might experience a failure to separate internal traumatic memories from their current visual reality. This biological blurring of boundaries could contribute to the overwhelming sensation that makes severe trauma memories so disorienting.
Because the research team conducted their brain imaging at a single point in time, the study cannot definitively determine the directionality of these relationships. It remains entirely unknown whether a natural variation in white matter integrity serves as a preexisting vulnerability that predisposes a person to intense traumatic memories after an event occurs.
Alternatively, the structural differences observed in the scans could be a biological consequence of repeatedly experiencing severe intrusive thoughts over time. The constant, repetitive retrieval of highly charged traumatic memories might physically alter the brain’s white matter pathways, similar to how repeated use changes a physical path through a forest.
Future research will require scientists to image trauma survivors repeatedly during the early aftermath of a distressing event, tracking how both the brain structure and the psychological symptoms evolve over several months or years. Additional studies involving controlled laboratory recall and naturalistic tracking in the exact same individuals could also clarify the biological overlap between voluntary and involuntary memories.
Through integrating the real-world tracking of memory experiences with advanced mapping of anatomical brain connections, researchers are gaining a deeper understanding of PTSD. Eventually, translating these physical variations into clinical profiles could help doctors pinpoint specific neural circuits, opening the door for treatments that target the specific memory symptoms a patient struggles with most.
The study, “Microstructural Integrity of Hippocampal–Posterior Cortical White Matter Is Associated With Phenomenological Properties of Trauma-Related Intrusive Memories,” was authored by Steven J. Granger, Boyu Ren, Kevin J. Clancy, Yara Pollmann, Justin T. Baker, and Isabelle M. Rosso.
-------------------------------------------------
Private, vetted email list for mental health professionals: https://www.clinicians-exchange.org
Unofficial Psychology Today Xitter to toot feed at Psych Today Unofficial Bot @PTUnofficialBot
-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #TraumaMemories #PTSDResearch #Hippocampus #WhiteMatter #Neuroimaging #DiffusionTensorImaging #IntrusiveMemories #MemoryReliving #BrainStructure #MentalHealthScience
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A new review paper on __The vicarious nature of hippocampal theta sequences__ in Philosophical Transactions of the Royal Society B. Reviewing the data and evidence that they really are about vicarious futures.
-
A new review paper on __The vicarious nature of hippocampal theta sequences__ in Philosophical Transactions of the Royal Society B. Reviewing the data and evidence that they really are about vicarious futures.
-
DATE: July 10, 2026 at 02:00PM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Neuroimaging study of 30,000 adults links the size of six brain areas to stronger working memory
A recent study published in the journal Neuropsychology suggests that having more physical tissue volume in six specific areas of the brain predicts better working memory in middle-aged and older adults. These findings provide evidence that preserving brain structure as we age supports our ability to temporarily hold and manipulate information. This knowledge could eventually guide new strategies to help slow cognitive decline in aging populations.
Working memory is the mental workspace that allows people to temporarily store and process information. People rely on this cognitive skill for everyday tasks like making decisions, learning new things, reading comprehension, and mental math. However, this mental capacity tends to decline as people reach their later years.
“Working memory is a fundamental cognitive function that we rely on every day, from following conversations, to planning tasks, and making decisions,” said study author Sarah Ellen Carnemolla, a postgraduate psychology student at Charles Sturt University.
In healthy aging, physical changes in the brain often happen before people notice any outward memory problems. Finding a link between the physical size of specific brain areas and memory performance might help experts identify who is most at risk for cognitive decline. This could also provide targets for therapies designed to protect the aging brain.
“We wanted to explore the topic of working memory in aging to deepen our understanding of the brain regions that support this crucial cognitive function, given that it naturally declines with age,” Carnemolla said. “Understanding the neurological basis of working memory is becoming more important with globally aging populations and increasingly common neurological and psychiatric conditions that affect working memory, such as ADHD and dementia.” By identifying the brain structures involved, the authors hope to contribute to future research aimed at improving quality of life for people experiencing memory impairments.
To measure working memory, experts often use a digit span task. In this traditional test, a person receives a sequence of numbers and must repeat them back. The backward version of this test requires the person to mentally reverse the order of the numbers. This demands extra mental effort and engages active manipulation skills.
Psychologists generally think of working memory as having a few separate parts. One part handles visual and spatial information, acting like a mental sketchpad. Another part handles verbal and auditory information, acting like a mental recording loop. An overarching executive system controls attention and coordinates these two storage areas to manage goal-directed behavior.
Past studies looking at the brain anatomy behind these skills have often relied on very small groups of people or individuals with severe brain injuries. Many previous projects also failed to account for outside factors that affect brain size, like a person’s age, biological sex, years of education, and overall head size. To address these gaps, authors wanted to test these relationships in a massive, healthy population using advanced brain scans.
To conduct the research, scientists analyzed data from the UK Biobank, which is a massive health database in the United Kingdom. The final sample included exactly 30,640 healthy adults between the ages of 51 and 80. Each participant completed a computerized memory assessment called the Numeric Memory Test.
During this visual test, a sequence of numbers appeared on a screen and then vanished after three seconds. Participants then had to type the numbers in reverse order using a digital keypad. The sequences became longer and more difficult as the test progressed, up to a maximum of 12 digits. The test ended when a person made too many consecutive mistakes.
Alongside the memory test, every participant underwent a magnetic resonance imaging (MRI) scan of their brain. This imaging technology uses strong magnets and radio waves to take detailed pictures of the body’s internal structures. The scientists used these images to measure the physical volume of 25 specific brain regions that previous literature linked to memory tasks.
Before running their statistical models, the scientists used specialized software to map out the different tissues in the brain. They separated the images into gray matter, white matter, and cerebrospinal fluid. This allowed them to isolate and measure the exact volume of the targeted areas with high precision.
The research team then used math to see if the sizes of these brain regions could predict how well someone performed on the memory test. They adjusted their equations to account for each person’s age, biological sex, years of education, and total intracranial volume. Intracranial volume simply refers to the total size of a person’s head and brain cavity.
The authors found that people with larger volumes in six specific brain areas tended to score higher on the memory test. One of these areas was the cerebellum, a region at the back of the brain traditionally known for coordinating movement. In this context, it likely helps people silently repeat the numbers to themselves, a strategy known as inner speech.
Another predictive region was the hippocampus, a seahorse-shaped structure deep in the brain. The hippocampus is famously linked to long-term memory formation, but this study suggests it also helps encode short-term visual information.
The other predictive areas included the superior temporal cortex and the insula, located on the sides of the brain. These regions typically help process sounds and manage attention. The insula in particular might help people switch their focus and ignore distractions while trying to remember the number sequence.
The left inferior parietal cortex and the left lateral occipital cortex also showed strong links to better test scores. These outer layers of the brain help people process visual and spatial information. Having more tissue in these regions likely assists in mentally picturing and rearranging the numbers like items on a mental chalkboard. “Our findings suggest that a network of brain regions plays an important role in supporting working memory throughout middle-age and older adulthood, and that the integrity of these brain structures matters for cognitive performance,” Carnemolla said.
However, the results also contained unexpected findings. When the statistical models accounted for all variables at once, three specific brain areas seemed to show a negative relationship with memory performance.
“Some brain regions showed associations with working memory performance that were in the opposite direction to what we expected (that is, for some regions, smaller size was associated with better performance),” Carnemolla told PsyPost. “We think this reflects the brain’s highly interconnected nature, where the influence of one region can be affected by its relationships with neighboring regions, making these patterns more complex than they first appear.”
Beyond brain anatomy, the study provides evidence that demographic factors heavily influence numeric memory. Older participants tended to remember fewer numbers than younger participants. At the same time, people with more years of formal education generally performed much better on the task than those with fewer years of schooling. “Our study also highlights the potential protective role of higher education in maintaining working memory as we age,” Carnemolla noted.
Interestingly, the researchers found no noticeable differences in performance between men and women. The overall size of a person’s head also did not predict how many numbers they could remember.
As a secondary goal, the researchers used this massive dataset to create benchmark scoring tables for the Numeric Memory Test. These tables group people by age, sex, and education level. Doctors can now use these charts to compare a new patient’s score against healthy peers, which makes it easier to spot abnormal memory problems.
The findings offer a detailed look at the aging brain, but the study does have some limitations. Because the data was collected at a single point in time, the researchers cannot prove that shrinking brain regions actually cause memory loss. It is only possible to say that brain volume and memory performance are related.
Additionally, the participant pool was not entirely representative of the general population. “Our study used data from the UK Biobank, whose participants tend to be more highly educated, of higher socioeconomic status, and predominantly of White ethnic backgrounds than the general population,” Carnemolla said. “This means the findings may not fully generalize to more diverse populations, highlighting the need for future research in broader and more representative groups.”
The visual format of the computerized test also allows people to simply read the numbers from right to left in their heads. This visual strategy might change how the brain tackles the problem compared to hearing numbers spoken aloud.
Future research should follow the same participants over many years to track how gradual brain shrinkage affects memory over time. The authors also suggest using a combination of different brain imaging techniques to build a more complete picture of how these regions communicate.
“As this was an Honors research project, my involvement with the study has now concluded,” Carnemolla said. “However, this work provides a foundation for future research into the brain networks that support working memory, including the potential for investigating how these findings might inform strategies to maintain or improve cognitive function across the lifespan.”
These future studies could help guide efforts to develop interventions that support or improve working memory. These strategies would take advantage of the brain’s natural capacity for change, a concept known as neuroplasticity. “Overall, the study reminds us that the health of our brain underpins many everyday abilities we often take for granted, and that understanding these relationships is an important step toward supporting cognitive health across the lifespan,” Carnemolla said.
To conclude, she offered gratitude to those who made the large-scale analysis possible. “We would like to sincerely thank the thousands of volunteers who generously contributed their time and data to the UK Biobank to advance our understanding of brain health and cognitive aging,” Carnemolla said.
The study, “Integrity in Six Key Brain Regions Predicts Numeric Working Memory Performance in 30,000 Middle-Aged and Older Adults: A UK Biobank Magnetic Resonance Imaging Study,” was authored by Sarah Ellen Carnemolla, Tanmoy Debnath, Md Geaur Rahman, and Minh Chau.
-------------------------------------------------
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-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #WorkingMemory #BrainHealth #AgingBrain #NeuroImaging #CognitiveAging #Hippocampus #Cerebellum #BrainVolume #UKBiobank #Neuroscience
-
DATE: July 10, 2026 at 02:00PM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Neuroimaging study of 30,000 adults links the size of six brain areas to stronger working memory
A recent study published in the journal Neuropsychology suggests that having more physical tissue volume in six specific areas of the brain predicts better working memory in middle-aged and older adults. These findings provide evidence that preserving brain structure as we age supports our ability to temporarily hold and manipulate information. This knowledge could eventually guide new strategies to help slow cognitive decline in aging populations.
Working memory is the mental workspace that allows people to temporarily store and process information. People rely on this cognitive skill for everyday tasks like making decisions, learning new things, reading comprehension, and mental math. However, this mental capacity tends to decline as people reach their later years.
“Working memory is a fundamental cognitive function that we rely on every day, from following conversations, to planning tasks, and making decisions,” said study author Sarah Ellen Carnemolla, a postgraduate psychology student at Charles Sturt University.
In healthy aging, physical changes in the brain often happen before people notice any outward memory problems. Finding a link between the physical size of specific brain areas and memory performance might help experts identify who is most at risk for cognitive decline. This could also provide targets for therapies designed to protect the aging brain.
“We wanted to explore the topic of working memory in aging to deepen our understanding of the brain regions that support this crucial cognitive function, given that it naturally declines with age,” Carnemolla said. “Understanding the neurological basis of working memory is becoming more important with globally aging populations and increasingly common neurological and psychiatric conditions that affect working memory, such as ADHD and dementia.” By identifying the brain structures involved, the authors hope to contribute to future research aimed at improving quality of life for people experiencing memory impairments.
To measure working memory, experts often use a digit span task. In this traditional test, a person receives a sequence of numbers and must repeat them back. The backward version of this test requires the person to mentally reverse the order of the numbers. This demands extra mental effort and engages active manipulation skills.
Psychologists generally think of working memory as having a few separate parts. One part handles visual and spatial information, acting like a mental sketchpad. Another part handles verbal and auditory information, acting like a mental recording loop. An overarching executive system controls attention and coordinates these two storage areas to manage goal-directed behavior.
Past studies looking at the brain anatomy behind these skills have often relied on very small groups of people or individuals with severe brain injuries. Many previous projects also failed to account for outside factors that affect brain size, like a person’s age, biological sex, years of education, and overall head size. To address these gaps, authors wanted to test these relationships in a massive, healthy population using advanced brain scans.
To conduct the research, scientists analyzed data from the UK Biobank, which is a massive health database in the United Kingdom. The final sample included exactly 30,640 healthy adults between the ages of 51 and 80. Each participant completed a computerized memory assessment called the Numeric Memory Test.
During this visual test, a sequence of numbers appeared on a screen and then vanished after three seconds. Participants then had to type the numbers in reverse order using a digital keypad. The sequences became longer and more difficult as the test progressed, up to a maximum of 12 digits. The test ended when a person made too many consecutive mistakes.
Alongside the memory test, every participant underwent a magnetic resonance imaging (MRI) scan of their brain. This imaging technology uses strong magnets and radio waves to take detailed pictures of the body’s internal structures. The scientists used these images to measure the physical volume of 25 specific brain regions that previous literature linked to memory tasks.
Before running their statistical models, the scientists used specialized software to map out the different tissues in the brain. They separated the images into gray matter, white matter, and cerebrospinal fluid. This allowed them to isolate and measure the exact volume of the targeted areas with high precision.
The research team then used math to see if the sizes of these brain regions could predict how well someone performed on the memory test. They adjusted their equations to account for each person’s age, biological sex, years of education, and total intracranial volume. Intracranial volume simply refers to the total size of a person’s head and brain cavity.
The authors found that people with larger volumes in six specific brain areas tended to score higher on the memory test. One of these areas was the cerebellum, a region at the back of the brain traditionally known for coordinating movement. In this context, it likely helps people silently repeat the numbers to themselves, a strategy known as inner speech.
Another predictive region was the hippocampus, a seahorse-shaped structure deep in the brain. The hippocampus is famously linked to long-term memory formation, but this study suggests it also helps encode short-term visual information.
The other predictive areas included the superior temporal cortex and the insula, located on the sides of the brain. These regions typically help process sounds and manage attention. The insula in particular might help people switch their focus and ignore distractions while trying to remember the number sequence.
The left inferior parietal cortex and the left lateral occipital cortex also showed strong links to better test scores. These outer layers of the brain help people process visual and spatial information. Having more tissue in these regions likely assists in mentally picturing and rearranging the numbers like items on a mental chalkboard. “Our findings suggest that a network of brain regions plays an important role in supporting working memory throughout middle-age and older adulthood, and that the integrity of these brain structures matters for cognitive performance,” Carnemolla said.
However, the results also contained unexpected findings. When the statistical models accounted for all variables at once, three specific brain areas seemed to show a negative relationship with memory performance.
“Some brain regions showed associations with working memory performance that were in the opposite direction to what we expected (that is, for some regions, smaller size was associated with better performance),” Carnemolla told PsyPost. “We think this reflects the brain’s highly interconnected nature, where the influence of one region can be affected by its relationships with neighboring regions, making these patterns more complex than they first appear.”
Beyond brain anatomy, the study provides evidence that demographic factors heavily influence numeric memory. Older participants tended to remember fewer numbers than younger participants. At the same time, people with more years of formal education generally performed much better on the task than those with fewer years of schooling. “Our study also highlights the potential protective role of higher education in maintaining working memory as we age,” Carnemolla noted.
Interestingly, the researchers found no noticeable differences in performance between men and women. The overall size of a person’s head also did not predict how many numbers they could remember.
As a secondary goal, the researchers used this massive dataset to create benchmark scoring tables for the Numeric Memory Test. These tables group people by age, sex, and education level. Doctors can now use these charts to compare a new patient’s score against healthy peers, which makes it easier to spot abnormal memory problems.
The findings offer a detailed look at the aging brain, but the study does have some limitations. Because the data was collected at a single point in time, the researchers cannot prove that shrinking brain regions actually cause memory loss. It is only possible to say that brain volume and memory performance are related.
Additionally, the participant pool was not entirely representative of the general population. “Our study used data from the UK Biobank, whose participants tend to be more highly educated, of higher socioeconomic status, and predominantly of White ethnic backgrounds than the general population,” Carnemolla said. “This means the findings may not fully generalize to more diverse populations, highlighting the need for future research in broader and more representative groups.”
The visual format of the computerized test also allows people to simply read the numbers from right to left in their heads. This visual strategy might change how the brain tackles the problem compared to hearing numbers spoken aloud.
Future research should follow the same participants over many years to track how gradual brain shrinkage affects memory over time. The authors also suggest using a combination of different brain imaging techniques to build a more complete picture of how these regions communicate.
“As this was an Honors research project, my involvement with the study has now concluded,” Carnemolla said. “However, this work provides a foundation for future research into the brain networks that support working memory, including the potential for investigating how these findings might inform strategies to maintain or improve cognitive function across the lifespan.”
These future studies could help guide efforts to develop interventions that support or improve working memory. These strategies would take advantage of the brain’s natural capacity for change, a concept known as neuroplasticity. “Overall, the study reminds us that the health of our brain underpins many everyday abilities we often take for granted, and that understanding these relationships is an important step toward supporting cognitive health across the lifespan,” Carnemolla said.
To conclude, she offered gratitude to those who made the large-scale analysis possible. “We would like to sincerely thank the thousands of volunteers who generously contributed their time and data to the UK Biobank to advance our understanding of brain health and cognitive aging,” Carnemolla said.
The study, “Integrity in Six Key Brain Regions Predicts Numeric Working Memory Performance in 30,000 Middle-Aged and Older Adults: A UK Biobank Magnetic Resonance Imaging Study,” was authored by Sarah Ellen Carnemolla, Tanmoy Debnath, Md Geaur Rahman, and Minh Chau.
-------------------------------------------------
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-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #WorkingMemory #BrainHealth #AgingBrain #NeuroImaging #CognitiveAging #Hippocampus #Cerebellum #BrainVolume #UKBiobank #Neuroscience
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RE: https://neuromatch.social/@elduvelle_neuro/116850195155224254
Hi all, please check our latest preprint (Tirole et al., 2026) that breaks the dogma of #HippocampalReplay being value-dependent!!
(but of course if there's anything we did not account for, please let us know, that's what preprints are for!!)
-
RE: https://neuromatch.social/@elduvelle_neuro/116850195155224254
Hi all, please check our latest preprint (Tirole et al., 2026) that breaks the dogma of #HippocampalReplay being value-dependent!!
(but of course if there's anything we did not account for, please let us know, that's what preprints are for!!)
-
~ New preprint, new thread! ~
My former colleagues at UCL Margot Tirole and Dan Bendor (not on Masto) have a new #HippocampalReplay preprint out, to which I contributed a little! Check out our thread and don't hesitate to share and comment!Why do we remember some experiences more than others?
Reactivations of neurons in the #Hippocampus (“replay”), particularly during sleep, may help consolidate memories; but when many experiences occur before going to bed, the brain must sort out what is worth replaying 😴
We investigated whether reward or recency helped prioritize experiences for replay in freely-moving rats. Surprisingly, we found that reward value does not influence replay! Instead, episode recency has a major effect, with the most recent episode being replayed the most!
Check the preprint for more: Time, but not reward, shapes replay-based episodic prioritization
... or read on for a thread on the main results! ⏬#NeuroRat #SpatialMemory #MemoryConsolidation #Neuroscience #MastoThread
1/12 🧵 -
~ New preprint, new thread! ~
My former colleagues at UCL Margot Tirole and Dan Bendor (not on Masto) have a new #HippocampalReplay preprint out, to which I contributed a little! Check out our thread and don't hesitate to share and comment!Why do we remember some experiences more than others?
Reactivations of neurons in the #Hippocampus (“replay”), particularly during sleep, may help consolidate memories; but when many experiences occur before going to bed, the brain must sort out what is worth replaying 😴
We investigated whether reward or recency helped prioritize experiences for replay in freely-moving rats. Surprisingly, we found that reward value does not influence replay! Instead, episode recency has a major effect, with the most recent episode being replayed the most!
Check the preprint for more: Time, but not reward, shapes replay-based episodic prioritization
... or read on for a thread on the main results! ⏬#NeuroRat #SpatialMemory #MemoryConsolidation #Neuroscience #MastoThread
1/12 🧵 -
DATE: June 30, 2026 at 10:00AM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Researchers discover a neural bridge between fear and physical reactions
New research reveals how different regions of the brain synchronize to connect the memory of a frightening event with the physical reaction it triggers. The discovery highlights a collaborative mechanism between two sides of the hippocampus during fear learning as groups of nerve cells coordinate their firing patterns. The findings were published in PNAS.
Research has historically divided the hippocampus into two functional halves. The top half, known as the dorsal region, was typically associated with mapping physical spaces and remembering contexts. The bottom half, called the ventral region, was thought to handle emotional processing and anxiety states.
These distinct roles are both necessary when an animal learns to fear a specific threat. The brain must encode the emotional weight of the danger while also remembering the environment where it occurred. Researchers have only recently begun to ask how these two distinct halves communicate to produce a cohesive memory of fear.
Marco N. Pompili, a neuroscientist at Aix-Marseille University, led the investigation alongside colleagues Noé Hamou and Sidney I. Wiener at the Collège de France. The team set out to directly compare the electrical activity in both halves of the rat hippocampus. They wanted to see if and how the two regions might combine their specific capacities during moments of stress.
To investigate this, the researchers continuously monitored individual nerve cells in four male rats. The animals wore a custom-built apparatus holding dozens of microscopic twisted wires. These wires were thin enough to pick up the faint electrical impulses from individual neurons without damaging the surrounding brain tissue.
Before any negative events occurred, the rats spent two days exploring the testing enclosures. They listened to audio tones without any negative consequences. This habituation phase established a baseline measurement for both their physical movement and their standard brain activity.
During this early phase, the animals occasionally stopped moving and rested. The researchers noted that this resting behavior looked physically similar to fearful freezing. By recording the baseline neural activity during true rest, the researchers could distinguish it from the brain activity of genuine terror later on.
The actual conditioning phase took place in a specific square box. The researchers played a warning tone for the rats, immediately followed by a mild foot shock. The animals quickly associated the sound with the unpleasant sensation.
In response to the association, the rats began to display a defensive behavior called freezing. Freezing is an evolutionary reaction where an animal remains completely immobile, serving as a biological indicator of fear expression.
During the test, the team had to account for basic movement altering the brain signals. The dorsal hippocampus is known to change its firing rate based purely on how fast an animal is walking. To ensure their results were accurate, the research team used mathematical formulas to subtract any changes in nerve cell activity caused simply by fluctuations in walking speed.
After filtering out the effects of basic movement, the unique responses to the fear conditioning emerged. The recorded brain activity shifted across the entire hippocampus as the rats learned to predict the shock. In the ventral region, nerve cells began firing rapidly in direct response to the warning tone.
This heightened firing confirmed the traditional expectation for the bottom half of the hippocampus. The ventral area processes the emotional meaning of a learned threat, reacting strongly to the cue that predicts pain.
However, the dorsal region of the hippocampus provided an unexpected result. Nerve cells in this upper area strongly altered their activity during the actual moments when the rats were frozen in fear. The neurons largely reduced their firing rates during this physical expression of terror, acting as a direct mirror to the behavioral state.
This discovery challenges older models of brain function because it shows that the dorsal hippocampus is not just a spatial map. Instead, it actively represents the physical state of fear expression, responding directly to the behavioral reality of the animal. It provides a more comprehensive representation of the animal’s state than previously believed.
The most striking discovery occurred when the researchers looked at how these two regions interacted with each other. They identified tight groups of neurons that fired in precise synchrony across both the top and bottom halves of the hippocampus. These synchronous groups are known as cell assemblies.
To find these cell assemblies, the team used advanced mathematical algorithms similar to tools designed to isolate individual voices in a crowded room. This allowed them to detect faint patterns of synchronized firing hidden within the noise of hundreds of active brain cells. The algorithms successfully picked out groups of neurons that consistently spiked in unison.
These mixed assemblies acted as brief bridges between the two distinct brain regions. They contained ventral nerve cells that were responding to the warning tone alongside dorsal nerve cells that were responding to the freezing behavior. By firing together at the exact same millisecond, these individual cells created a unified brain network.
A single mixed assembly could theoretically bind the emotional memory of a threat to the physical response it demands. The researchers suggest this bridging mechanism allows the brain to build a multifaceted record of a frightening experience. The brain can coordinate what happened, the emotional weight of the event, and what the body did to survive.
The brain must rapidly link the recognition of a threat with a defensive physical state. The coordinated firing of these mixed cell assemblies provides a biological pathway for that rapid connection. It indicates the hippocampus functions as an integrated whole rather than two isolated compartments.
The study relies entirely on male rats, which presents a basic limitation. Biological differences between sexes can influence brain activity and learning processes. The authors note that future research must include female rodents to confirm if these brain synchronization patterns are universal.
Additionally, observing the synchronization of these cell assemblies does not prove that they directly command the animal to freeze. The researchers suggest that future experiments could artificially trigger these synchronized cell groups using optogenetics or other precise stimulation tools. This would clarify whether the assemblies merely record the fearful experience or actively drive the animal’s physical behavior.
The study, “Integration of fear learning and fear expression across the dorsoventral axis of the hippocampus,” was authored by Marco N. Pompili, Noé Hamou, and Sidney I. Wiener.
-------------------------------------------------
Private, vetted email list for mental health professionals: https://www.clinicians-exchange.org
Unofficial Psychology Today Xitter to toot feed at Psych Today Unofficial Bot @PTUnofficialBot
-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #FearLearning #Hippocampus #NeuralSynchronization #DorsalVsVentralHippocampus #CellAssemblies #FearExpression #NeuroscienceNews #BrainResearchers #PNAS #NeuralBridges
-
DATE: June 30, 2026 at 10:00AM
SOURCE: PSYPOST.ORG** Research quality varies widely from fantastic to small exploratory studies. Please check research methods when conclusions are very important to you. **
-------------------------------------------------TITLE: Researchers discover a neural bridge between fear and physical reactions
New research reveals how different regions of the brain synchronize to connect the memory of a frightening event with the physical reaction it triggers. The discovery highlights a collaborative mechanism between two sides of the hippocampus during fear learning as groups of nerve cells coordinate their firing patterns. The findings were published in PNAS.
Research has historically divided the hippocampus into two functional halves. The top half, known as the dorsal region, was typically associated with mapping physical spaces and remembering contexts. The bottom half, called the ventral region, was thought to handle emotional processing and anxiety states.
These distinct roles are both necessary when an animal learns to fear a specific threat. The brain must encode the emotional weight of the danger while also remembering the environment where it occurred. Researchers have only recently begun to ask how these two distinct halves communicate to produce a cohesive memory of fear.
Marco N. Pompili, a neuroscientist at Aix-Marseille University, led the investigation alongside colleagues Noé Hamou and Sidney I. Wiener at the Collège de France. The team set out to directly compare the electrical activity in both halves of the rat hippocampus. They wanted to see if and how the two regions might combine their specific capacities during moments of stress.
To investigate this, the researchers continuously monitored individual nerve cells in four male rats. The animals wore a custom-built apparatus holding dozens of microscopic twisted wires. These wires were thin enough to pick up the faint electrical impulses from individual neurons without damaging the surrounding brain tissue.
Before any negative events occurred, the rats spent two days exploring the testing enclosures. They listened to audio tones without any negative consequences. This habituation phase established a baseline measurement for both their physical movement and their standard brain activity.
During this early phase, the animals occasionally stopped moving and rested. The researchers noted that this resting behavior looked physically similar to fearful freezing. By recording the baseline neural activity during true rest, the researchers could distinguish it from the brain activity of genuine terror later on.
The actual conditioning phase took place in a specific square box. The researchers played a warning tone for the rats, immediately followed by a mild foot shock. The animals quickly associated the sound with the unpleasant sensation.
In response to the association, the rats began to display a defensive behavior called freezing. Freezing is an evolutionary reaction where an animal remains completely immobile, serving as a biological indicator of fear expression.
During the test, the team had to account for basic movement altering the brain signals. The dorsal hippocampus is known to change its firing rate based purely on how fast an animal is walking. To ensure their results were accurate, the research team used mathematical formulas to subtract any changes in nerve cell activity caused simply by fluctuations in walking speed.
After filtering out the effects of basic movement, the unique responses to the fear conditioning emerged. The recorded brain activity shifted across the entire hippocampus as the rats learned to predict the shock. In the ventral region, nerve cells began firing rapidly in direct response to the warning tone.
This heightened firing confirmed the traditional expectation for the bottom half of the hippocampus. The ventral area processes the emotional meaning of a learned threat, reacting strongly to the cue that predicts pain.
However, the dorsal region of the hippocampus provided an unexpected result. Nerve cells in this upper area strongly altered their activity during the actual moments when the rats were frozen in fear. The neurons largely reduced their firing rates during this physical expression of terror, acting as a direct mirror to the behavioral state.
This discovery challenges older models of brain function because it shows that the dorsal hippocampus is not just a spatial map. Instead, it actively represents the physical state of fear expression, responding directly to the behavioral reality of the animal. It provides a more comprehensive representation of the animal’s state than previously believed.
The most striking discovery occurred when the researchers looked at how these two regions interacted with each other. They identified tight groups of neurons that fired in precise synchrony across both the top and bottom halves of the hippocampus. These synchronous groups are known as cell assemblies.
To find these cell assemblies, the team used advanced mathematical algorithms similar to tools designed to isolate individual voices in a crowded room. This allowed them to detect faint patterns of synchronized firing hidden within the noise of hundreds of active brain cells. The algorithms successfully picked out groups of neurons that consistently spiked in unison.
These mixed assemblies acted as brief bridges between the two distinct brain regions. They contained ventral nerve cells that were responding to the warning tone alongside dorsal nerve cells that were responding to the freezing behavior. By firing together at the exact same millisecond, these individual cells created a unified brain network.
A single mixed assembly could theoretically bind the emotional memory of a threat to the physical response it demands. The researchers suggest this bridging mechanism allows the brain to build a multifaceted record of a frightening experience. The brain can coordinate what happened, the emotional weight of the event, and what the body did to survive.
The brain must rapidly link the recognition of a threat with a defensive physical state. The coordinated firing of these mixed cell assemblies provides a biological pathway for that rapid connection. It indicates the hippocampus functions as an integrated whole rather than two isolated compartments.
The study relies entirely on male rats, which presents a basic limitation. Biological differences between sexes can influence brain activity and learning processes. The authors note that future research must include female rodents to confirm if these brain synchronization patterns are universal.
Additionally, observing the synchronization of these cell assemblies does not prove that they directly command the animal to freeze. The researchers suggest that future experiments could artificially trigger these synchronized cell groups using optogenetics or other precise stimulation tools. This would clarify whether the assemblies merely record the fearful experience or actively drive the animal’s physical behavior.
The study, “Integration of fear learning and fear expression across the dorsoventral axis of the hippocampus,” was authored by Marco N. Pompili, Noé Hamou, and Sidney I. Wiener.
-------------------------------------------------
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Unofficial Psychology Today Xitter to toot feed at Psych Today Unofficial Bot @PTUnofficialBot
-------------------------------------------------
#psychology #counseling #socialwork #psychotherapy @psychotherapist @psychotherapists @psychology @socialpsych @socialwork @psychiatry #mentalhealth #psychiatry #healthcare #depression #psychotherapist #FearLearning #Hippocampus #NeuralSynchronization #DorsalVsVentralHippocampus #CellAssemblies #FearExpression #NeuroscienceNews #BrainResearchers #PNAS #NeuralBridges
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🧠 How does the #hippocampus keep a spatial map stable while adding aversive context?
Miguel-López et al. show that in mice running on a linear belt, #CA3 #axonal population activity preserved a common spatial #manifold across baseline, air puff and probe sessions. The aversive cue did not erase the map, but deformed it, embedding affective information into the same #representational geometry:
-
🧠 How does the #hippocampus keep a spatial map stable while adding aversive context?
Miguel-López et al. show that in mice running on a linear belt, #CA3 #axonal population activity preserved a common spatial #manifold across baseline, air puff and probe sessions. The aversive cue did not erase the map, but deformed it, embedding affective information into the same #representational geometry:
-
🐭Did we meet? Just like humans, sleepy mice forget their social encounters after a bad night.
Neuroscientist Robbert Havekes & UG team found that the asthma drug roflumilast brings back these social memories after sleep deprivation.😴
Curious? Read more 👇
🔗https://www.rug.nl/fse/news/highlighted-papers/2026/slaperige-muis-vergeet-ontmoetingen-een-astmamedicijn-brengt-herinneringen-terug🧪 #SciComm #ScienceNewsroom #neuroscience #biology #neurobiology #nature #memory #hippocampus #research #science #engineering #scientistsOnMastodon
@universityofgroningen -
🐭Did we meet? Just like humans, sleepy mice forget their social encounters after a bad night.
Neuroscientist Robbert Havekes & UG team found that the asthma drug roflumilast brings back these social memories after sleep deprivation.😴
Curious? Read more 👇
🔗https://www.rug.nl/fse/news/highlighted-papers/2026/slaperige-muis-vergeet-ontmoetingen-een-astmamedicijn-brengt-herinneringen-terug🧪 #SciComm #ScienceNewsroom #neuroscience #biology #neurobiology #nature #memory #hippocampus #research #science #engineering #scientistsOnMastodon
@universityofgroningen -
🗺️🐀 How does the #brain map uneven terrain? New paper by @rmgrieves, @elduvelle_neuro & Taube suggests that the #hippocampal map is shaped by terrain #geometry itself, not only by where the animal runs. Slopes, ridges & surface contours may act as spatial structure for #PlaceCells. Read more about in the 🧵👇
📄 https://doi.org/10.1126/sciadv.adz9893
"Hippocampal #PlaceCells map terrain geometry independently of #behavior"#Hippocampus #SpatialNavigation #Neuroscience https://fediscience.org/@rmgrieves/116692850991318267
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🗺️🐀 How does the #brain map uneven terrain? New paper by @rmgrieves, @elduvelle_neuro & Taube suggests that the #hippocampal map is shaped by terrain #geometry itself, not only by where the animal runs. Slopes, ridges & surface contours may act as spatial structure for #PlaceCells. Read more about in the 🧵👇
📄 https://doi.org/10.1126/sciadv.adz9893
"Hippocampal #PlaceCells map terrain geometry independently of #behavior"#Hippocampus #SpatialNavigation #Neuroscience https://fediscience.org/@rmgrieves/116692850991318267
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RE: https://fediscience.org/@rmgrieves/116692850991318267
“This is a hill I’ll die on!” - says the scientist feeding smelly paste to rats running in a home-made maze with hills and troughs just like the waves in the rat’s brain and the emotions in the scientist’s life… 🏔️ 🌊 🧠
@rmgrieves 's latest paper is out, with rats on hills, #PlaceCells recordings and modelling looking at how the brain maps real-life environments: Hippocampal place cells map terrain geometry independently of behavior
It was great fun to work with him and Jeff Taube on this, even with all the emotional rollercoasters (inherent to science-making)!
#Neuroscience #Hippocampus #3DMapping #NeuroRat #SpatialCognition
-
RE: https://fediscience.org/@rmgrieves/116692850991318267
“This is a hill I’ll die on!” - says the scientist feeding smelly paste to rats running in a home-made maze with hills and troughs just like the waves in the rat’s brain and the emotions in the scientist’s life… 🏔️ 🌊 🧠
@rmgrieves 's latest paper is out, with rats on hills, #PlaceCells recordings and modelling looking at how the brain maps real-life environments: Hippocampal place cells map terrain geometry independently of behavior
It was great fun to work with him and Jeff Taube on this, even with all the emotional rollercoasters (inherent to science-making)!
#Neuroscience #Hippocampus #3DMapping #NeuroRat #SpatialCognition
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💁🏻♀️ TIL: Using ultra-thin Neuropixels probes, #Baylor College researchers found the #hippocampus processes #speech and predicts upcoming #words during #anesthesia. 🧠
Over 70% of #neurons distinguished unexpected #sounds from predictable ones. This challenges the idea that understanding #language requires consciousness. 😪
👉 https://www.sciencenews.org/article/brain-cells-listen-under-anesthesia
#neuroscience #brain #hearing #science #houston #nature #learning
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💁🏻♀️ TIL: Using ultra-thin Neuropixels probes, #Baylor College researchers found the #hippocampus processes #speech and predicts upcoming #words during #anesthesia. 🧠
Over 70% of #neurons distinguished unexpected #sounds from predictable ones. This challenges the idea that understanding #language requires consciousness. 😪
👉 https://www.sciencenews.org/article/brain-cells-listen-under-anesthesia
#neuroscience #brain #hearing #science #houston #nature #learning
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How does the #brain adapt when goals change? This study shows that coordinated neural rhythms between medial #OrbitofrontalCortex & #hippocampus underlie flexible #navigation, allowing animals to rapidly update internal maps & switch between target locations @PLOSBiology https://plos.io/4x5yN2M
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How does the #brain adapt when goals change? This study shows that coordinated neural rhythms between medial #OrbitofrontalCortex & #hippocampus underlie flexible #navigation, allowing animals to rapidly update internal maps & switch between target locations @PLOSBiology https://plos.io/4x5yN2M
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Modeling suggests that sparse #CA3 input can speed up #learning of new #SpatialMaps, while dense #CA1 coding provides a more efficient, compressed representation for large-scale #navigation.
🧵2/2
#Neuroscience #Hippocampus #SpatialNavigation #NeuralDynamics
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Modeling suggests that sparse #CA3 input can speed up #learning of new #SpatialMaps, while dense #CA1 coding provides a more efficient, compressed representation for large-scale #navigation.
🧵2/2
#Neuroscience #Hippocampus #SpatialNavigation #NeuralDynamics
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New paper by Maimon et al (Ulanovsky lab): recordings from #bats flying through tunnels up to 200 m reveal a sparse-to-dense transformation between #hippocampal #CA3 and #CA1.
In small environments, CA3 and CA1 #PlaceCells look similar. At large spatial scales, however, CA3 #neurons mostly show single, ultrasparse #PlaceFields, while CA1 neurons show dense multifield coding.
🌍 https://doi.org/10.1038/s41586-026-10537-0
🧵1/2
#Neuroscience #Hippocampus #SpatialNavigation #NeuralDynamics
-
New paper by Maimon et al (Ulanovsky lab): recordings from #bats flying through tunnels up to 200 m reveal a sparse-to-dense transformation between #hippocampal #CA3 and #CA1.
In small environments, CA3 and CA1 #PlaceCells look similar. At large spatial scales, however, CA3 #neurons mostly show single, ultrasparse #PlaceFields, while CA1 neurons show dense multifield coding.
🌍 https://doi.org/10.1038/s41586-026-10537-0
🧵1/2
#Neuroscience #Hippocampus #SpatialNavigation #NeuralDynamics
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Stress disrupts hippocampal integration of overlapping events, memory inference
https://www.science.org/doi/10.1126/sciadv.aea5496?user_id=66c4bf745d78644b3aa57b08
#HackerNews #stress #memory #neuroscience #hippocampus #research #science
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Stress disrupts hippocampal integration of overlapping events, memory inference
https://www.science.org/doi/10.1126/sciadv.aea5496?user_id=66c4bf745d78644b3aa57b08
#HackerNews #stress #memory #neuroscience #hippocampus #research #science
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#EmotionalIntelligence #MemoryScience #FutureMindset #BrainHealth #Hippocampus #PsychologyExplained #ConsciousMind #wellnesscoaching #wellnessfitness #wellnesscenter #wellnesscommunity #wellnesslife #EmotionsMatter #PersonalGrowth #MentalWellness #NeuroReels https://mastodon.social/@biohackingpathway/116648373479758838
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#EmotionalIntelligence #MemoryScience #FutureMindset #BrainHealth #Hippocampus #PsychologyExplained #ConsciousMind #wellnesscoaching #wellnessfitness #wellnesscenter #wellnesscommunity #wellnesslife #EmotionsMatter #PersonalGrowth #MentalWellness #NeuroReels https://mastodon.social/@biohackingpathway/116648373479758838
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🧠 New preprint by Lu et al: Recordings from the human #hippocampus and anterior cingulate #cortex during three distinct tasks reveal that #NeuralPopulation activity is not fully task-specific. About half of the low-dimensional #NeuralSubspace structure was shared across tasks, suggesting a stable population geometry that may support flexible #cognition across different #behaviors.
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🧠 New preprint by Lu et al: Recordings from the human #hippocampus and anterior cingulate #cortex during three distinct tasks reveal that #NeuralPopulation activity is not fully task-specific. About half of the low-dimensional #NeuralSubspace structure was shared across tasks, suggesting a stable population geometry that may support flexible #cognition across different #behaviors.
-
Pharma-Insider enthüllt: So werden Pandemien geplant
https://friendica.ambag.es/display/e0590d38-1669-d1de-932e-61b205480560
-
Pharma-Insider enthüllt: So werden Pandemien geplant
https://friendica.ambag.es/display/e0590d38-1669-d1de-932e-61b205480560
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Sleep, Stress, and Your IQ: How Everyday Habits Quietly Shape Your Cognitive Performance
If sleep deprivation is the blunt instrument that batters cognitive performance, chronic stress is the slow poison. The biological mechanism is well understood, and its effects on the brain regions most critical to intelligence are profound.
https://iqcertificate.org/blog/sleep-stress-and-your-iq
#sleep #stre #iq #intelligence #brain #cortisol #memory #health #Hippocampus #neuroscience #psychiatry #nutrition #caffeine #meditation
-
Sleep, Stress, and Your IQ: How Everyday Habits Quietly Shape Your Cognitive Performance
If sleep deprivation is the blunt instrument that batters cognitive performance, chronic stress is the slow poison. The biological mechanism is well understood, and its effects on the brain regions most critical to intelligence are profound.
https://iqcertificate.org/blog/sleep-stress-and-your-iq
#sleep #stre #iq #intelligence #brain #cortisol #memory #health #Hippocampus #neuroscience #psychiatry #nutrition #caffeine #meditation
-
Preparing some slides on my favourite topic of the moment - #HippocampalReplay - for some colleagues, starting from lecture slides I made about 8 years ago...
and I keep crossing stuff or adding "BUT see xx" or "actually not" or "Now controversial!" to about half of the results that I was taking from granted 8 years ago 👀Is there any such thing as a scientific fact?!
-
Preparing some slides on my favourite topic of the moment - #HippocampalReplay - for some colleagues, starting from lecture slides I made about 8 years ago...
and I keep crossing stuff or adding "BUT see xx" or "actually not" or "Now controversial!" to about half of the results that I was taking from granted 8 years ago 👀Is there any such thing as a scientific fact?!
-
Tom is now listening to baseball
https://open.spotify.com/track/5lO1htX1UPjwyItDLurhR5 -
#studien zeigen, dass anhaltender Stress mit strukturellen Veränderungen im #hippocampus und im präfrontalen Kortex in Verbindung steht – Bereiche, die für #gedächtnis #Emotionsregulation und Entscheidungsprozesse wichtig sind. #Stresshormone wie #cortisol spielen dabei eine zentrale Rolle.
Quellen: McEwen, B. S. (2007). Physiology and neurobiology of stress and adaptation: Central role of the brain. Physiological Reviews, 87(3), 873–904.
-
Mehrteilig:
Gedanken allein lassen das Gehirn nicht „wachsen“ oder „schrumpfen“. Doch chronischer Stress kann messbare Auswirkungen auf bestimmte Hirnregionen haben.
Quellen: McEwen, B. S. (2007). Physiology and neurobiology of stress and adaptation: Central role of the brain. Physiological Reviews, 87(3), 873–904.
#Stress #Neuroplastizität #Gehirn #Psychologie #Hippocampus #fblifestyle
-
Mehrteilig:
Gedanken allein lassen das Gehirn nicht „wachsen“ oder „schrumpfen“. Doch chronischer Stress kann messbare Auswirkungen auf bestimmte Hirnregionen haben.
Quellen: McEwen, B. S. (2007). Physiology and neurobiology of stress and adaptation: Central role of the brain. Physiological Reviews, 87(3), 873–904.
#Stress #Neuroplastizität #Gehirn #Psychologie #Hippocampus #fblifestyle
-
Tom is now listening to Bambi
https://open.spotify.com/track/5dmPNuHmRRJuHmJTDa7NuJ -
🧠 New preprint by Chericoni et al: #NeuralPopulation activity in the #hippocampus encodes spatial information for different agents (self, prey, gaze) in distinct but related low-dimensional subspaces. The study shows that these representations can be linearly transformed between each other, suggesting a shared geometric code supporting flexible spatial #cognition and multi-agent navigation.
