Scientists discover a surprising brain benefit of eating peanuts every day

 Eating peanuts every day may offer surprising benefits for the aging brain. Researchers at Maastricht University Medical Center in the Netherlands have found that regularly consuming unsalted, skin-roasted peanuts can improve how certain brain regions respond to insulin in older adults. The findings come from the Institute of Nutrition and Translational Research in Metabolism (NUTRIM) and were published in the peer-reviewed journal Food & Function.

Although insulin is best known for regulating blood sugar, it also plays an essential role in the brain. It helps nerve cells grow, survive, and communicate with one another, supporting memory and other cognitive abilities. Healthy insulin signaling may also help protect against processes associated with Alzheimer's disease.

After participants consumed peanuts daily for 16 weeks, researchers observed improved insulin responsiveness in a group of brain regions in the right hemisphere. These included portions of the lingual gyrus, hippocampus, parahippocampal gyrus, and posterior cingulate gyrus, all of which contribute to memory-related processes.

"The hormone insulin plays an important role in the brain, where it supports memory and other cognitive processes. As people age, the brain may become less responsive to insulin, which has been linked to age-related cognitive decline," says Dr. Peter Joris, the study's senior author and an associate professor in the Department of Nutrition and Movement Sciences, NUTRIM, Maastricht University Medical Center. "Our study found that daily peanut consumption beneficially affected insulin responsiveness in memory-related brain regions in older adults. These findings suggest that enhanced regional brain insulin responsiveness may contribute to the cognitive benefits of unsalted, skin-roasted peanut intake."

Daily Peanuts Linked to Better Memory and Brain Blood Flow

The study included 31 healthy adults between the ages of 60 and 75. During the peanut consumption phase, participants ate 60 grams (approximately two servings) of peanuts each day for 16 weeks. Researchers used a randomized, controlled crossover trial, a rigorous study design that allowed them to compare the effects of eating peanuts with those of avoiding them.

The new findings build on earlier research by Joris published in 2025. That investigation found that consuming peanuts for 16 weeks increased overall cerebral blood flow (CBF) by 3.6% and improved verbal memory performance by 5.8%.

Cerebral blood flow measures how much blood circulates through the brain, carrying oxygen and nutrients that brain cells need to function properly. It is an important indicator of the health of the brain's blood vessels. Those earlier results appeared in the peer-reviewed journal Clinical Nutrition.

How Scientists Measured the Effects of Peanuts on the Brain

One distinguishing feature of the NUTRIM research was its combination of a carefully controlled dietary intervention lasting several months with sophisticated brain imaging technology.

To examine changes in brain function, researchers used arterial spin labeling magnetic resonance imaging (ASL-MRI), a technique that measures blood flow in different regions of the brain. They evaluated insulin responsiveness by tracking changes in regional cerebral blood flow after insulin was administered through the nose.

The team also used abdominal MRI scans to measure fat accumulation in the liver, known as intrahepatic lipid (IHL) content. Cognitive abilities were assessed using the Cambridge Neuropsychological Test Automated Battery (CANTAB), a standardized collection of computerized tests.

Researchers believe several components of peanuts may contribute to their observed effects on brain health, rather than any single nutrient being responsible.

"Multiple nutrients present in peanuts, including unsaturated fats, dietary fiber, vitamins and minerals and bioactive phytochemicals, could potentially contribute to the observed brain benefits," says Joris. "Peanuts are also a good source of plant-based protein and are especially rich in L-arginine. L-arginine is a key precursor of nitric oxide (NO), which has been reported to facilitate learning and memory performance."

What Participants Ate During the 16-Week Study

To ensure participants consumed a consistent amount, researchers supplied premeasured packets of skin-roasted peanuts throughout the peanut intervention period.

Participants were instructed to eat their peanuts in the morning or afternoon, but they could choose how to incorporate them into their daily routine. They could consume the entire portion at once, divide it into smaller amounts throughout the day, or include the peanuts in their meals.

During the control phase, participants avoided peanuts entirely. After 16 weeks, they switched to the opposite study condition, allowing researchers to compare brain health measurements under both dietary approaches.

Source: ScienceDaily

Wearable ultrasound patch boosts REM sleep without drugs or surgery

 Researchers led by the University of Texas at Austin have created a soft wearable patch that improved REM sleep in real-world testing without medication or surgery. Known as NEUSLeeP, the device combines gentle ultrasound stimulation with electrodes that track brain activity as it happens. This allows the patch to influence deep areas of the brain involved in sleep while also monitoring the brain's response.

"This is the first time we've been able to noninvasively target deep brain regions involved in REM sleep, while simultaneously monitoring brain activity," said Kai Wing "Kevin" Tang, a recent UT biomedical engineering Ph.D. graduate who led the research effort. "Our skin-attached NEUSLeeP patch opens up new possibilities for understanding sleep and treating sleep disorders in home settings," added Huiliang "Evan" Wang, assistant professor in the Cockrell School of Engineering's Department of Biomedical Engineering, who supervised Tang's work and served as the principal investigator (PI) directing the overall project.

Wearable Patch Helps People Reach REM Faster

The researchers tested the technology in a study involving 28 people, with the results published in Nature Communications. On average, participants entered REM sleep 43 minutes sooner and remained in that stage for about 16 minutes longer.

The benefits were observed in both healthy sleepers and participants experiencing some sleep difficulties. Users also described the patch as comfortable and safe, and the study reported minimal adverse effects.

Possible Benefits for Stress and Emotional Health

Among healthy participants, NEUSLeeP stimulation also increased heart rate variability, which is commonly used as an indicator of the body's ability to respond to stress. Brain imaging revealed changes in circuits associated with emotion, raising the possibility that the technology could support mood regulation and psychological resilience.

"REM sleep is not just about dreaming -- it's about emotional reset and stress adaptation," explained Gregory Fonzo, assistant professor in the Dell Medical School's Department of Psychiatry and Behavioral Sciences and one of the project's co-PIs. "By enhancing REM, we may help people better cope with stress and improve their overall well-being."

REM sleep disruptions have been associated with depression, anxiety and post-traumatic stress disorder (PTSD). Current approaches to sleep problems, including medication and behavioral therapy, may cause side effects or may not directly address the underlying factors that interfere with REM sleep.

Future Trials for Insomnia, Depression and PTSD

The team plans to conduct larger studies to verify the initial results and evaluate whether NEUSLeeP could help people with PTSD, depression and chronic insomnia. The researchers also see potential uses in home sleep monitoring, neuroscience research and personalized sleep treatments.

"Our vision is a future where patients with mental health disorders can optimize their sleep with a noninvasive and safe treatment," said Vincent Mysliwiec, M.D., a professor at UT Health San Antonio, a leading expert in sleep disorders, and another co-PI on the project. "This technology could help millions of people get the restorative sleep they need."

Researchers Move Toward Commercialization

The team is collaborating with Discovery to Impact, UT's commercialization unit, in an effort to move the technology toward the market. A patent application has also been filed for the device.

Other team members are William D. Moscoso-Barrera, Mengxia Yu, Mengmeng Yao, Jinmo Jeong, Ilya Pyatnitskiy, Anakaren Romero Lozano, Jiachen Wang, Ju-Chun Hsieh, Tony Sungjin Chae, Daniel Song, Julieta Garcia, Rithvik Mittapalli and Adam Bush of the Department of Biomedical Engineering; Benjamin Baird of the College of Natural Sciences' Department of Psychology; and Wynn Legon of Virginia Tech's Fralin Biomedical Research Institute.

Source: ScienceDaily

Depression may shut down the brain’s ability to make new neurons

 Most of the brain's roughly 100 billion neurons are produced before birth. However, the small number of new neurons that continue to form in the adult hippocampus may play an important role in protecting against depression, according to new research from Columbia University Vagelos College of Physicians and Surgeons.

The findings provide the first evidence that neurogenesis, the process of producing new neurons, stalls in the brains of adults with major depressive disorder. Researchers also identified molecular programs involved in controlling this process, offering potential clues for developing new treatments.

"Historically, depression was thought to be a disease of neurotransmitter deficiency, especially serotonin, but we now think that depression stems from multiple issues that affect our neurons' ability to adapt to stress and changing environments," says Maura Dupont, professor of psychiatry, who led the research.

"Without the ability to create new neurons, people with depression may not have the resilience to effectively adapt to the environment."

How New Neurons May Shape Memory and Emotion

The researchers focused on the hippocampus, a brain region that plays a major role in episodic memory and emotional responses to the environment. It is also one of the few areas of the adult brain that continues to generate new neurons.

Although the hippocampus is not the only brain region involved in depression, its influence over both memory and emotion has made it an important area of study. Researchers believe changes there may contribute to the tendency of people with depression to interpret experiences more negatively.

"The hippocampus is important for our ability to distinguish between similar but different memories and separate the emotional connotation of past memories and current events," Dupont says.

This ability is known as pattern separation. When it becomes impaired, individual memories and the emotions attached to them may become less distinct, allowing separate experiences to blend together.

"You may be out with a friend for lunch, but she's tired and doesn't talk much. With intact pattern separation, you remember this as a unique event. With impaired pattern separation, it becomes mixed with previous memories of feeling rejected, leading you to think, 'They're upset with me'," Dupont explains. "And I see this a lot in my patients, where they can only retrieve negative information from their memories."

Research in mice has shown that adult neurogenesis is necessary for pattern separation. A recent study involving patients with brain tumors, in whom neurogenesis was eliminated by radiation therapy directed at the hippocampus, suggests that the same relationship may exist in humans.

"It's important to emphasize that we do not yet know the complete mechanism, particularly in humans, but the newborn neurons seem to enhance pattern separation because they are especially responsive to new experiences and can be incorporated into new memory circuits more easily, allowing new memories to be stored separately from the old ones," Dupont says. "Turning neurogenesis back on may be a way to treat depression in some people by rewiring their hippocampus circuit."

Depression Affects More Than New Neuron Growth

The researchers found that the changes linked to depression extended well beyond neurogenesis. New neuron formation operates within a larger hippocampal circuit that stores episodic memories along with their emotional significance, and molecular disruptions appeared throughout that system.

The affected genes included those involved in building new connections between neurons, supporting communication among brain cells, supplying cellular energy, and moving materials within cells.

The trisynaptic circuit, the hippocampus's primary pathway for establishing new emotional memories, also displayed evidence of inflammation and cellular stress in people with depression.

To identify these changes, researchers studied nearly half a million brain cells collected from people with depression and control subjects shortly after each donor's death.

Using an array of recently developed techniques, the team measured the activity of every gene within individual cells and examined whether cellular proteins had been altered. This enormous dataset allowed researchers to see what individual cells were doing and determine exactly where affected cells were located within the hippocampal circuit.

Genes, Environment, and the Biology of Depression

The analysis revealed altered activity in several genes whose genetic variants have previously been associated with major depression.

Other disrupted genes showed epigenetic changes that may reflect the influence of environmental factors. Epigenetic mechanisms can adjust how strongly genes are turned on or off without altering the underlying DNA sequence.

"These are like dimmer switches that control how active genes are, and they are affected by life experiences such as stress, learning, aging, chemicals, etc.," Dupont says.

The diversity of molecular changes may also help explain why depression can look so different from one person to another.

"Overall, the wide range of effects we found could reflect different pathogenetic mechanisms, perhaps indicating that depression is not just one disease," she adds.

Researchers still have only a limited understanding of depression's underlying biology, according to Dupont. By defining the disorder more precisely at the cellular and molecular levels, studies like this one could eventually provide new targets for treatment.

Source: ScienceDaily

Children at risk for depression get “stuck” on sad faces

 A smile or a frown may reveal more than emotion alone. The faces that capture a child's attention could provide important clues about their mental health and how depression develops.

New research from Binghamton University, State University of New York, suggests that depression may influence how strongly children focus on emotional expressions such as happy or sad faces. The pattern appears to differ depending on whether a child has a family history of depression.

Researchers at the Mood Disorders Institute at Binghamton University study how depression develops in children and adolescents, with particular attention to how family history and emotional experiences may influence vulnerability over time. By identifying these patterns while children are still developing, scientists hope to better understand who may be at greater risk and eventually improve prevention strategies.

"Most of the vulnerabilities that we focus on are still developing during this time period," said Brandon Gibb, director of the Mood Disorders Institute and SUNY distinguished professor of psychology. "You can catch things as they're developing, rather than only studying them once they're already there and pretty stable."

Following Children's Attention Over Time

Earlier research has linked depression with greater attention to sad faces. However, those associations have generally been modest, and scientists have not been sure whether biased attention contributes to depression or develops because of it.

The Binghamton study was designed to investigate that question by tracking both depressive symptoms and attention patterns over time. According to the researchers, it is the first study to examine how changes in each may predict later changes in the other among children.

"The real novel piece is that we looked at these transactional relations," said Kelly Gair, a PhD student at Binghamton and lead author of the paper. "Between attentional biases and depressive symptoms, we looked at the way that they were mutually predicting one another across the time points, which is especially novel and hasn't been done before."

The research team, which also included Leslie A. Brick from the University of New Mexico, followed 242 children and their mothers for two years. Participants were assessed every six months.

During each visit, children viewed pairs of faces on a screen. One face showed a neutral expression, while the other displayed an emotion (happy, sad, or angry). Eye tracking technology measured which face held the child's attention and for how long.

Children in the study looked at faces conveying different emotions onscreen, and eye tracking technology recorded where their attention veered. Photo credit: NimStim Set of Facial Expressions (Tottenham et al., 2009).

Family History Changes the Pattern

The results suggest that increasing depressive symptoms do not affect every child's attention in the same way. Family history appeared to play an important role.

Among children whose mothers had a history of major depressive disorder, rising depressive symptoms were associated with greater attention to sad faces. In other words, as these children experienced more symptoms themselves, their attention became increasingly drawn toward expressions of sadness.

"For those who are already at risk, the more these children experience depression themselves, the more they lose their ability to pull their attention away from the sad things around them," Gibb said.

"We know that when you're depressed, it changes what you pay attention to," Gair said. "Our results suggest that these changes may be more long-lasting and may differ depending on family history. One thought is that for children of mothers with depression, who are exposed to more facial displays of sadness from interactions with their mom, these types of facial expressions become even more salient when they experience depression themselves, so their attention becomes increasingly stuck on sad expressions."

Happy Faces May Lose Their Pull

A different pattern emerged among children whose mothers had no history of depression.

When depressive symptoms increased in these children, they did not become more focused on sad expressions. Instead, they paid less attention to happy faces.

"In our lower-risk children, what seems to be happening is that experiences of depression are eroding a protective factor, which is how much they pay attention to happy faces," Gibb said.

The distinction suggests that depression may alter emotional attention through different pathways depending on a child's underlying level of familial risk. For some children, sadness may become increasingly difficult to ignore. For others, positive emotional signals may simply become less likely to capture their attention.

Source: ScienceDaily

What happens in the brain when cannabis makes you anxious?

 Northwestern scientists have identified, for the first time, a specific group of neurons -- cells in the brain -- that appear to contribute to anxiety caused by cannabinoid drugs, particularly when those drugs are combined with stressful conditions. Cannabinoids are a category of substances that includes THC, the main psychoactive ingredient in cannabis.

To investigate how cannabinoids influence fear and anxiety, researchers exposed mice to a threatening smell derived from fox urine. Before encountering the odor, the animals were given either a placebo or a synthetic cannabinoid drug.

Mice that received the cannabinoid froze more frequently and spent less time exploring the predator scent. Researchers traced these anxiety related behaviors to increased activity in a small population of brain cells known as somatostatin neurons. These neurons are located in the central amygdala, an area of the brain involved in processing fear and stress.

When the researchers genetically silenced the somatostatin neurons, the mice that received the cannabinoid became less likely to avoid the predator odor. The result suggested that these cells play an important role in producing the anxious response.

"The results of this study could explain why a good trip can turn bad pretty quickly if people consume too much cannabis or the situation they are in turns stressful or scary," said study senior author Dr. Sachin Patel, chair of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine.

The study was published on Oct. 2 in Nature Communications.

Tracking the Brain During a Threat

Patel and his colleagues gave mice several different doses of the synthetic cannabinoid and measured their reactions to the predator odor. The researchers recorded how much time the animals spent near the scent and whether they responded by freezing or fleeing.

At the same time, the team monitored activity inside the brain by implanting a small microscope into the mice's brain.

Researchers also studied brain tissue to determine how cannabinoids changed communication between neurons. Their experiments showed that the drug weakened a natural brain mechanism that normally acts as a "brake" on somatostatin neurons. With that restraint reduced, the neurons became more active.

"Higher doses of cannabinoids and environmental stress worked together to synergistically release the 'brake' on the central amygdala, which in turn drove excessive anxiety," Patel explained.

Why Cannabis and Anxiety Matter

Cannabis use in the U.S. has steadily increased in recent years. At the same time, emergency department visits involving adverse effects from the drug have also risen.

Previous studies have found an association between cannabis use and a higher long term risk of anxiety. Anxiety and mood disorders are also on the rise globally.

"Understanding how cannabis affects brain function to generate its psychoactive effects could ultimately reveal new ways to counteract negative consequences should they arise in some people," Patel said.

The researchers believe the findings may also have relevance beyond cannabis related side effects. Patel said the same neurons could potentially represent a broader target for understanding or reducing anxiety.

"Suppressing the activity of somatostatin neurons in the central amygdala could represent a final pathway for reducing anxiety symptoms, not just in the context of cannabis side effects," he explained.

Other Northwestern co-authors are Farhana Yasmin, Saptarnab Naskar, Danyal Zaidi, Isaac Kandil, Michelle Kwon and Dr. Luis Rosas-Vidal.

The study is titled, "Cannabinoid Modulation of Central Amygdala Population Dynamics During Threat Investigation." It was supported by the National Institutes of Health (grants MH100785 and K08 MH126166) and the Brain & Behavior Research Foundation's Young Investigator Awards.

Source: ScienceDaily

Scientists discover 5 hidden brain patterns behind depression

 Two people diagnosed with depression can experience vastly different symptoms. One might struggle with persistent anxiety and repetitive negative thoughts, while another may experience trauma related symptoms or substance abuse. But do these differences also appear in the way their brains function?

Researchers at the University of Helsinki investigated this question and uncovered a striking finding: people with the same depression diagnosis can have dramatically different patterns of brain activity. In some cases, communication between brain regions was unusually strong, while in others, it was weaker than normal.

Depression is a major global health concern. According to the World Health Organization (WHO, 2025), approximately 332 million (5.2%) adults worldwide are affected. In Finland, depression is the leading individual cause of both extended sick leave and disability pensions.

Brain Study Reveals Five Distinct Depression Profiles

To investigate the biological differences associated with depression, researchers examined brain activity in 263 people diagnosed with major depressive disorder and 75 healthy participants who served as a comparison group.

The analysis revealed five distinct groups based on differences in functional connectivity, a measure of how closely activity in different brain regions is coordinated. When two regions show synchronized activity, it suggests they are working together as part of a larger brain network. However, stronger connectivity does not necessarily mean the brain is functioning better.

"What was particularly interesting was the contrasting patterns of brain activity found under the umbrella of the same depression diagnoses. In some individuals, the functional connectivity between brain regions was stronger than usual, while in others it was weaker," says Director Satu Palva of the Neuroscience Center, University of Helsinki.

These differences were also associated with particular symptoms. Participants in one group showed especially strong connections between brain regions, along with more pronounced substance abuse problems. Another group displayed weaker connections and a greater prominence of post-traumatic stress disorder (PTSD) symptoms.

The contrasting results could help explain why earlier studies examining the brains of people with depression have sometimes reached conflicting conclusions. If researchers study different combinations of patients, they may observe very different patterns, even though everyone involved has received the same diagnosis.

The findings add to growing evidence that depression may not have a single, consistent biological signature. Instead, the condition could involve several distinct patterns of brain function.

The Five Brain Patterns Linked to Depression

The researchers classified participants with depression into five groups based on how strongly different brain areas communicated and the frequencies at which their activity was coordinated.

Each group had a characteristic pattern of brain connectivity and associated symptoms:

Group 1: Strong connectivity and severe symptoms

Participants generally showed relatively strong connections between brain regions. This profile was associated with more severe symptoms across several areas, including depression, anxiety, rumination, and reduced ability to function in daily life. Rumination refers to repeatedly dwelling on distressing thoughts, worries, or negative experiences.

Group 2: Weaker connectivity and milder depression

This group was characterized by relatively weak communication between brain regions. Compared with the other groups, participants generally experienced milder symptoms.

Group 3: Widespread weak connectivity and trauma symptoms

People in this group showed reduced connectivity across substantial portions of the brain. Symptoms associated with post-traumatic stress disorder (PTSD) were particularly prominent.

Group 4: Mixed connectivity and multiple challenges

This profile combined unusually strong connections in some brain regions with weaker connections in others. Participants tended to experience more severe depression, greater substance abuse problems, and lower overall well-being.

Group 5: The strongest connectivity and substance abuse symptoms

Participants in the fifth group had the strongest connections between brain regions of any group identified in the study. Substance abuse was a particularly prominent issue, while trauma related symptoms were less pronounced than in the other groups.

Source:ScienceDaily

Yale scientists discover how stress changes the brain to make memories stronger

 Stress does more than influence how we feel. It can also change what we remember, particularly when an experience is emotionally intense or personally meaningful. Scientists have long known that cortisol, a hormone released during stressful situations, can strengthen emotional memories. What has been less clear is exactly how this happens inside the brain.

Researchers at Yale University have now uncovered important clues. Their study reveals that cortisol strengthens emotional memories by changing how brain networks involved in emotion and memory function and communicate with one another. The findings offer a deeper understanding of why certain experiences leave such powerful impressions while others quickly fade.

"We all experience stress, and my lab is interested in understanding how stress can be helpful," said corresponding author Elizabeth Goldfarb, an assistant professor of psychiatry at Yale School of Medicine and of psychology in the Faculty of Arts and Sciences.

The findings were published in the journal Science Advances.

How Stress Hormones Influence Memory

Previous research involving both humans and rodents has shown that stress and cortisol can improve memory for emotional events. Scientists also know that certain brain regions, including the amygdala, play an essential role in this process. The amygdala is particularly important for processing emotions and identifying experiences that may be significant.

However, understanding precisely how cortisol strengthens memories has been challenging. Many brain regions participate in several mental functions, making it difficult to determine whether the hormone is influencing emotional responses, memory formation, or both.

"Forming memories for emotional experiences involves different processes in the brain: first, perceiving an experience as emotional or intense, and second, encoding that experience into long-term memory," said Goldfarb, who is also a member of Yale's Wu Tsai Institute, an interdisciplinary research initiative that explores cognition.

The researchers wanted to examine these processes separately to determine how cortisol affects the brain's ability to recognize emotional significance and preserve an experience as a lasting memory.

Watching the Brain Form Emotional Memories

To investigate, the Yale team conducted an experiment in which participants took a pill containing either hydrocortisone, a form of cortisol, or an inactive placebo. They then viewed a series of pictures while undergoing functional MRI (fMRI) scanning.

This imaging technique measures changes in blood flow and oxygen levels associated with brain activity, allowing researchers to identify which areas of the brain are more active during different tasks.

As participants examined the pictures, they reported their emotional reactions to each image. The following day, researchers tested how well they remembered what they had seen.

Each person completed the experiment twice, once after receiving hydrocortisone and once after receiving the placebo. The study used a double blind design, meaning neither the participants nor the experimenter knew which substance had been administered during a particular session.

This approach allowed the scientists to compare how the same person's brain responded with and without the additional cortisol.

A Five-Second Look at Brain Network Activity

One of the study's most important advances came from the way researchers analyzed the brain scans.

Scientists often study a measurement called functional connectivity, which describes how closely activity in different parts of the brain fluctuates together. When two regions show synchronized patterns of activity, it can indicate that they are participating in related processes.

Traditionally, examining these relationships requires several minutes of brain imaging data. The Yale team instead analyzed functional connectivity during individual trials lasting only around five seconds.

Using these brief snapshots, the researchers tested whether patterns of brain activity could predict two different outcomes: how emotionally intense participants found a picture and whether they would remember that picture the following day.

The approach worked for both. By identifying patterns associated with emotional intensity and memory formation separately, the scientists were able to examine how cortisol influenced each network and the interactions between them.

This gave the researchers a more detailed picture of the changing brain activity associated with emotional memory formation.

Source: ScienceDaily