Category: Mental Health

Categories : Mental Health NeurologyTags :

Improper ‘Pruning’ of Brain Connections may Cause Teen Mental Health Disorders

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Problems with the brain’s ability to ‘prune’ itself of unnecessary connections may underlie a wide range of mental health disorders that begin during adolescence, according to research published in Nature Medicine.

The findings, from an international collaboration, led by researchers in the UK, China and Germany, may help explain why people are often affected by more than one mental health disorder, and may in future help identify those at greatest risk.

One in seven adolescents (aged 10-19 years old) worldwide experiences mental health disorders, according to the World Health Organization (WHO). Depression, anxiety and behavioural disorders, such as attention deficit hyperactivity disorder (ADHD), are among the leading causes of illness and disability among young people, and adolescents will commonly have more than one mental health disorder.

Many mental health problems emerge during adolescence, such as depression and anxiety, which manifest as ‘internalising’ symptoms, including low mood and worrying. Other conditions such as attention deficit hyperactivity disorder (ADHD) manifest as ‘externalising’ symptoms, such as impulsive behaviour.

Professor Barbara Sahakian from the Department of Psychiatry at the University of Cambridge said: “Young people often experience multiple mental health disorders, beginning in adolescence and continuing – and often transforming – into adult life. This suggests that there’s a common brain mechanism that could explain the onset of these mental health disorders during this critical time of brain development.”

In the study, the researchers say they have identified a characteristic pattern of brain activity among these adolescents, which they have termed the ‘neuropsychopathological factor’, or NP factor for short.

The team examined data from 1,750 adolescents, aged 14 years, from the IMAGEN cohort, a European research project examining how biological, psychological, and environmental factors during adolescence may influence brain development and mental health. In particular, they examined imaging data from brain scans taken while participants took part in cognitive tasks, looking for patterns of brain connectivity – in other words, how different regions of the brain communicate with each other.

Adolescents who experienced mental health problems – regardless of whether their disorder was one of internalising or externalising symptoms, or whether they experienced multiple disorders – showed similar patterns of brain activity. These patterns – the NP factor – were largely apparent in the frontal lobes, the area at the front of the brain responsible for executive function which, among other functions, controls flexible thinking, self-control and emotional behaviour.

The researchers confirmed their findings by replicating them in 1799 participants from the ABCD Study in the USA, a long-term study of brain development and child health, and by studying patients who had received psychiatric diagnoses.

When the team looked at genetic data from the IMAGEN cohort, they found that the NP factor was strongest in individuals who carried a particular variant of the gene IGSF11 that has been previously associated with multiple mental health disorders. This gene is known to play an important role in synaptic pruning, a process whereby unnecessary brain connections – synapses – are discarded. Problems with pruning may particularly affect the frontal lobes, since these regions are the last brain areas to complete development in adolescents and young adults.

Dr Tianye Jia from the Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China and the Institute of Psychiatry, Psychology & Neuroscience, King’s College London, London, UK said: “As we grow up, our brains make more and more connections. This is a normal part of our development. But too many connections risk making the brain inefficient. Synaptic pruning helps ensure that brain activity doesn’t get drowned out in ‘white noise’.

“Our research suggests that when this important pruning process is disrupted, it affects how brain regions talk to each other. As this impact is seen most in the frontal lobes, this then has implications for mental health.”

The researchers say that the discovery of the NP factor could help identify those young people at greatest risk of compounding mental health problems.

Professor Jianfeng Feng from Fudan University in Shanghai, China, and the University of Warwick, UK, said: “We know that many mental health disorders begin in adolescence and that individuals who develop one disorder are at increased risk of developing other disorders, too. By examining brain activity and looking for this NP factor, we might be able to detect those at greatest risk sooner, offering us more opportunity to intervene and reduce this risk.”

Source: University of Cambridge

Categories : Mental Health Substance UseTags :

Suicide Attempts Show Increasing Exposures to Cannabis

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Analysis of US poison centre data has shown that suspected suicidal cannabis exposures have increased 17% annually, over a period of 12 years. According to the study published in the journal JAMA Network Open, more than 92%, involved other substances in addition to cannabis, and the data cannot show a direct causal link between cannabis and suicide attempts.

Still, the findings are cause for concern, the researchers said, especially since the increase was more pronounced among children and women during and after the pandemic.

“This study adds to already ample evidence that cannabis use, particularly by younger people, has significant implications for mental health,” said study co-author Tracy Klein, a WSU associate professor of nursing. “We don’t have evidence that cannabis alone was the primary driver of a suicide attempt, but we do know that cannabis can worsen certain mental health conditions and increase impulsivity.”

The researchers found 18,698 cases of intentional, suspected suicide cannabis exposures reported to U.S. poison centers from 2009 to 2021. Of these cases, 9.6% resulted in death or major outcomes such as permeant disability. The researchers noted that while more of these exposures involved younger people, severe consequences occurred more often among people 65 and older.  

U.S. poison centers take calls 24-hours a day from households and healthcare facilities to provide toxicology expertise in suspected poisoning cases. They also investigate the causes, often following up with patients and doctors to determine if patients took substances intentionally or not.

It is well known that accidental cannabis poisonings have been increasing since many states legalized cannabis. Some policies can help prevent these unintentional cases, Klein said, such as packaging guidelines so edible cannabis products are not mistaken for candy.

Intentional cannabis poisonings, on the other hand, have not been well studied, which is one of the reasons the researchers undertook this analysis, and their findings point to the need for more mental health services.

“We have a significant shortage of mental health and primary care providers in the United States,” Klein said. “We know that mental health needs not only changed but became even more acute during the COVID-19 emergency. Cannabis is one part of that.”

Other research has shown that cannabis use is associated with depression and anxiety in youth and that it may interfere with brain development as well. Recent studies have also suggested a link between suicidal ideation and cannabis use in young people. Given this evidence, it is especially important to limit youth access to cannabis, said Janessa Graves, first author and a WSU nursing associate professor.  

“Children and adolescents shouldn’t be able to purchase or access cannabis,” Graves said. “We also need to educate kids and parents around the risks of cannabis. I think many people just aren’t aware the impacts cannabis can have on brain development, and on behavioural and mental health, especially in adolescents and young adults.”

Source: Washington State University

Categories : Addiction Mental HealthTags :

ADHD Stimulant Drugs have Potential for Abuse at Schools that Carry Them

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Researchers have identified a strong association between prevalence of prescription stimulant therapy for attention-deficit/hyperactivity disorder (ADHD) and rates of prescription stimulant misuse by students in US middle and high schools. Published in JAMA Network Open, the study highlights the need for assessments and education in schools and communities to prevent medication-sharing among teens. This is especially important considering non-medical use of prescription stimulants among teens remains more prevalent [PDF] than misuse of any other prescription drug, including opioids and benzodiazepines.  

The study used data collected between 2005 and 2020 by the Monitoring the Future (MTF) study. MTF is a large, multicohort survey of legal and illicit drug use among American adolescents in eighth, 10th, and 12th grade.

“The drug supply has rapidly changed, and what looks like medications – bought online or shared among friends or family members – can contain fentanyl or other potent illicit substances that can result in overdoses. It’s important to raise awareness of these new risks for teens,” said NIDA Director Nora Volkow, MD. “It’s also essential to provide the necessary resources and education to prevent misuse and support teens during this critical period in their lives when they encounter unique experiences and new stressors.”

Stimulant therapy is an evidence-based treatment for ADHD, but it can also be harmful if used without prescription or guidance from clinicians. Prolonged stimulant misuse can lead to several detrimental health effects including cardiovascular conditions, depressed mood, overdoses, psychosis, anxiety, seizures, and stimulant use disorder.

Previous studies have shown that more than half of adolescents who misuse prescription stimulants get the medication for free from friends or relatives. While diagnoses of ADHD and prescribing of stimulant therapy for ADHD have increased significantly in the United States over the past 20 years, few studies have looked at the relationship between stimulant therapy and prescription stimulant misuse in schools. This is the first large, national study to examine prevalence of prescription stimulant misuse and factors correlating with prevalence among students in eighth, 10th, and 12th grade across the U.S.

Researchers at the University of Michigan examined both school- and individual-level characteristics associated with prescription stimulant misuse. Across 231 141 student participants surveyed at 3,284 secondary schools, the school-level prevalence of nonmedical use varied from 0% to over 25% of students. Schools with a greater number of students (12% or higher) reporting prescription stimulant therapy for ADHD tended to have the highest percentages of their student body reporting prescription stimulant misuse (8% of total student body). By comparison, schools with fewer students (0 to 6% of student body) reporting stimulant therapy for ADHD were associated with lower rates of prescription stimulant misuse (4 to 5% of student body).

Other features of schools that were associated with increased rates of misuse included having a higher proportion of parents with higher levels of education, being located in non-Northeastern regions of the US and in suburban areas, having a higher proportion of non-Hispanic white students, and showing “medium-level” (10-19% of total student body) binge drinking. However, the association between school prevalence of stimulant therapy for ADHD and prescription stimulant misuse remained strong when accounting for prevalence of other types of substance use and numerous other individual- and school-level sociodemographics.

Recent research from this team expands on the associations found in this study, including a study that suggested teens with a history of taking both stimulant or non-stimulant medications for ADHD are at high risk for prescription stimulant misuse, as well as cocaine and methamphetamine use. The researchers note that it is important to interpret these results as associations, not causations, and that the primary goal of these kinds of studies is to inform effective preventative and support [PDF] strategies for teens.

“The key takeaway here is not that we need to lessen prescribing of stimulants for students who need them, but that we need better ways to store, monitor, and screen for stimulant access and use among youth to prevent misuse,” said study author Sean Esteban McCabe, PhD. “There’s variation in stimulant misuse across different schools, so it’s important to assess schools and implement personalised interventions that work best for each school. It’s also critical to treat and educate teens on prescription stimulants as the medications they are intended to be and limit their availability as drugs of misuse.”

Source: National Institutes of Health

Categories : Gender Mental HealthTags :

Researchers Tie Sex-specific Genes to Depression

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Depression is widely reported to be more common in women than in men, with women twice as likely to receive a diagnosis than men. A new study published in Nature has found that there are differences between male and female genes and how they relate to depression.

In a genome-wide association(GWA} study, the McGill University researchers analysed the genomes of more than 270 000 individuals. They found that sex-specific prediction methods were more accurate in forecasting an individual’s genetic risk of developing depression than prediction methods that did not specify sex. The researchers found 11 areas of DNA that were linked to depression in females, and only one area in males.

In both males and females, genetic correlations were significant between the broad depression GWA and other psychopathologies; however, correlations with educational attainment and metabolic features including body fat, waist circumference, waist-to-hip ratio and triglycerides were significant only in females. Gene-based analysis showed 147 genes significantly associated with broad depression in the total sample, 64 in the females and 53 in the males.

Despite the biological processes involved in depression being similar in males and females, researchers found that different genes were involved for each sex. This information can be useful to identify future sex-specific treatments for depression.  “This is the first study to describe sex-specific genetic variants associated with depression, which is a very prevalent disease in both males and females. These findings are important to inform the development of specific therapies that will benefit both men and women while accounting for their differences,” says Dr Patricia Pelufo Silveira, lead author and Associate Professor in the Department of Psychiatry. “In the clinic, the presentation of depression is very different for men and women, as well as their response to treatment, but we have very little understanding of why this happens at the moment.”

Source: McGill University

Categories : Exercise Mental Health PaediatricsTags :

Regular Physical Activity can Improve Mental Health of Young Adolescents

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Regular physical activity can improve young adolescents’ mental health and help with behavioural difficulties, suggests research published in Mental Health and Physical Activity. Investigators found that engaging in regular moderate to vigorous physical activity at age 11 was associated with better mental health between the ages of 11 and 13.

Physical activity was also associated with reduced hyperactivity and behavioural problems, such as loss of temper, fighting with other children, lying, and stealing, in young people.

Researchers from the Universities of Edinburgh, Strathclyde, Bristol, and Georgia in the United States explored data from the Children of the 90s study (also known as the Avon Longitudinal Study of Parents and Children; ALSPAC). They looked at the levels of physical activity of 4755 11-year-olds which was measured using devices.

The devices recorded levels of moderate physical activity, typically defined as brisk walking or cycling, as well as vigorous activity which boosts heart rate and breathing, such as aerobic dancing, jogging or swimming.

The young people and their parents reported on their levels of depressive symptoms from age 11 and at age 13 years. Participants’ parents and teachers were also quizzed about the young people’s general behaviour and emotional difficulties.

In analysing the impact of moderate to vigorous exercise on the young people’s mental health and behaviour, the team also considered factors such as age, sex and socio-economic status.

They found that higher levels of moderate or intense physical activity had a small but detectable association with decreases in depressive symptoms and emotional difficulties.

Regular exercise had a small but detectable association with reduced behavioural problems, even after controlling for other possible influences, the study found.

The findings suggest regular moderate and intense physical activity may have a small protective influence on mental health in early adolescence, researchers say.

Dr Josie Booth, of the University of Edinburgh’s Moray House School of Education and Sport, said: “This study adds to the increasing evidence base about how important physical activity is for all aspects of young people’s development – it can help them feel better, and do better at school. Supporting young people to lead healthy active lives should be prioritised.”

Researchers say the study is the first to offer such a comprehensive approach to examining mental health and exercise in young people.

Professor John Reilly, at the University of Strathclyde, said: “While it might seem obvious that physical activity improves mental health the evidence for such a benefit in children and young people has been scarce, so the study findings are important. The findings are also important because levels of moderate-to-vigorous intensity activity globally are so low in pre-teens globally – less than a third achieve the 60 minutes per day recommended by the WHO and UK Health Departments.”

The study is a long-term health-research project that enrolled more than 14 000 pregnant women in 1991 and 1992.

Children of the 90s has been following the health and development of the parents and their children in detail and is currently recruiting the children and the siblings of the original children into the study. It receives core funding from the Medical Research Council, the Wellcome Trust and the University of Bristol.

Source: University of Edinburgh

Categories : Mental HealthTags :

Exercise for Managing Depression has Greater Efficacy than Meds or Counselling

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University of South Australia researchers are calling for exercise to be a mainstay approach for managing depression as a new study shows that physical activity is 1.5 times more effective than counselling or the leading medications.

Published in the British Journal of Sports Medicine, the review is the most comprehensive to date, encompassing 97 reviews, 1039 trials and 128 119 participants. It shows that physical activity is extremely beneficial for improving symptoms of depression, anxiety, and distress.

Specifically, the review showed that exercise interventions that were 12 weeks or shorter were the most effective at reducing mental health symptoms, highlighting the speed at which physical activity can make a change.

The largest benefits were seen among people with depression, pregnant and postpartum women, healthy individuals, and people diagnosed with HIV or kidney disease.

According to the World Health Organization, one in every eight people worldwide (970 million people) live with a mental disorder. 

Lead UniSA researcher, Dr Ben Singh, says physical activity must be prioritised to better manage the growing cases of mental health conditions.

“Physical activity is known to help improve mental health. Yet despite the evidence, it has not been widely adopted as a first-choice treatment,” Dr Singh says.

“Our review shows that physical activity interventions can significantly reduce symptoms of depression and anxiety in all clinical populations, with some groups showing even greater signs of improvement.

“Higher intensity exercise had greater improvements for depression and anxiety, while longer durations had smaller effects when compared to short and mid-duration bursts.

“We also found that all types of physical activity and exercise were beneficial, including aerobic exercise such as walking, resistance training, Pilates, and yoga.

“Importantly, the research shows that it doesn’t take much for exercise to make a positive change to your mental health.”

Senior researcher, UniSA’s Prof Carol Maher, says the study is the first to evaluate the effects of all types of physical activity on depression, anxiety, and psychological distress in all adult populations.

“Examining these studies as a whole is an effective way for clinicians to easily understand the body of evidence that supports physical activity in managing mental health disorders.

“We hope this review will underscore the need for physical activity, including structured exercise interventions, as a mainstay approach for managing depression and anxiety.”

Source: University of South Australia

Categories : Mental Health NeurologyTags :

Receptor Location is Key when Rebuilding Neural Connections with Psychedelic Drugs

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When using psychedelic drugs to treat mental illness, it’s all down to location when rapidly rebuilding connections between nerve cells. In their paper published in Science, scientists show that engaging serotonin 2A receptors inside neurons promotes growth of new connections – but engaging the same receptor on the surface of nerve cells does not.

The findings will help guide efforts to discover new drugs for depression, PTSD and other disorders, according to senior author David E. Olson, associate professor at the University of California, Davis.

Drugs such as LSD, MDMA and psilocybin show great promise for treating a wide range of mental disorders that are characterised by a loss of neural connections. In laboratory studies, a single dose of these drugs can cause rapid growth of new dendrites from nerve cells, and formation of new spines on those dendrites.

Olson calls this group of drugs “psychoplastogens” because of their ability to regrow and remodel connections in the brain.

Earlier work from Olson’s and other labs showed that psychedelic drugs work by engaging the serotonin 2A receptor (5-HT2AR). But other drugs that engage the same receptor, including serotonin, do not have the same growth effects.

Maxemiliano Vargas, a graduate student in Olson’s lab, Olson and colleagues experimented with chemically tweaking drugs and using transporters to make it easier or harder for compounds to slip across cell membranes. Serotonin itself is polar, meaning it dissolves well in water but does not easily cross the lipid membranes that surround cells. The psychedelics, on the other hand, are much less polar and can easily enter the interior of a cell.

They found that the growth-promoting ability of compounds was correlated with the ability to cross cell membranes.

Drug receptors are usually thought of as being located on the cell membrane, facing out. But the researchers found that in nerve cells, serotonin 2A receptors were concentrated inside cells, mostly around a structure called the Golgi body, with some receptors on the cell surface. Other types of signalling receptors in the same class were on the surface.

The results show that there is a location bias in how these drugs work, Olson said. Engaging the serotonin 2A receptor when it is inside a cell produces a different effect from triggering it when it is on the outside.

“It gives us deeper mechanistic insight into how the receptor promotes plasticity, and allows us to design better drugs,” Olson said.

Source: University of California – Davis

Categories : Mental Health Metabolic DisordersTags :

Self-stigma Linked to Worse Blood Glucose Control in Type 1 Diabetes

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Because of their illness, patients with chronic medical conditions may experience self-stigma, or negative beliefs, emotional reactions, and behaviours towards themselves. New research published in the Journal of Diabetes Investigation found a link between self-stigma and glycated haemoglobin (HbA1c) in adults with type 1 diabetes.

The study included 109 adults in Japan with type 1 diabetes who completed questionnaires that generated scores based on a self-stigma scale. Although the findings support a link between self-stigma and sub-optimal HbA1c, additional studies are needed to show whether this is a causal relationship.

“We focused on this issue through clinical experiences with people with type 1 diabetes, whose glycaemic management improved markedly by social supports of eliminating diabetes-related stigma. Although the finding of an association between self-stigma and HbA1c is significant, further longitudinal research is required to determine whether self-stigma leads to sub-optimal HbA1c,” said corresponding author Yukiko Onishi MD, PhD, of the Institute of Medical Science, Asahi Life Foundation, in Tokyo. “This research does support and highlight the importance of eliminating self-stigma when treating people with type 1 diabetes.”

Source: Wiley

Categories : Mental Health Obstetrics & GynaecologyTags :

During Pregnancy, Experiencing Racism Worsens Depression

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In a recent study published in The Journal of Advanced Nursing that included pregnant Black women from multiple US states, feeling upset by experiences of racism in the 12 months prior to delivery was associated with significantly higher odds of depression during pregnancy.

Perinatal depression is defined as major or minor depressive episodes that occur during pregnancy or in the first 12 months after birth. Mothers with perinatal depression often report symptoms including depressed mood; loss of interest or pleasure in daily activities; changes in weight, appetite and sleep; poor concentration; feelings of hopelessness; and suicidal ideations. Non-Hispanic Black women are twice as likely to experience symptoms of depression and suicidal ideations during the perinatal period than White women.

For this study, 7328 women answered survey questions. The findings showed that 11.4% of respondents reported feeling upset due to experiences of racism, and 11.4% reported experiencing depression during pregnancy. After adjusting for confounding factors, respondents who reported feeling upset due to the experience of racism had over two-fold higher odds of experiencing depression during pregnancy compared with respondents who did not report feeling upset due to the experience of racism.

“Our findings reinforce the importance of respectful maternity care, given the mental health impacts of experiences of racism during the perinatal period,” the authors wrote. “Racism is a powerful structural determinant of health with roots in a historical system of oppression that persists today in health care practices and policies. Perinatal health care providers, in collaboration with public health and other health disciplines, are ideally positioned to address inequities in maternal and child health that are rooted in racism.”

Source: Wiley

Categories : Mental Health NeurologyTags :

Why do People Remember Emotional Events Better?

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Most people remember emotional events, like their wedding day, very clearly, but researchers are not sure how the human brain prioritises emotional events in memory. In a study published in Nature Human Behaviour, Joshua Jacobs, associate professor of biomedical engineering at Columbia Engineering, and his team identified a specific neural mechanism in the human brain that tags information with emotional associations for enhanced memory.

The team demonstrated that high-frequency brain waves in the amygdala, a hub for emotional processes, and the hippocampus, a hub for memory processes, are critical to enhancing memory for emotional stimuli. Disruptions to this neural mechanism, brought on either by electrical brain stimulation or depression, impair memory specifically for emotional stimuli.

Rising prevalence of memory disorders

The rising prevalence of memory disorders such as dementia has highlighted the damaging effects that memory loss has on individuals and society. Disorders such as depression, anxiety, and post-traumatic stress disorder (PTSD) can also feature imbalanced memory processes, especially with the COVID pandemic. Understanding how the brain naturally regulates what information gets prioritised for storage and what fades away could provide critical insight for developing new therapeutic approaches to strengthening memory for those at risk of memory loss, or for normalising memory processes in those at risk of dysregulation.

“It’s easier to remember emotional events, like the birth of your child, than other events from around the same time,” says Salman E. Qasim, lead author of the study, who started this project during his PhD in Jacobs’ lab at Columbia Engineering. “The brain clearly has a natural mechanism for strengthening certain memories, and we wanted to identify it.”

The difficulty of studying neural mechanisms in humans

Most investigations into neural mechanisms take place in animals such as rats, because such studies require direct access to the brain to record brain activity and perform experiments that demonstrate causality, such as careful disruption of neural circuits. But it is difficult to observe or characterise a complex cognitive phenomenon like emotional memory enhancement in animal studies.

To study this process directly in humans. Qasim and Jacobs analysed data from memory experiments conducted with epilepsy patients undergoing direct, intracranial brain recording for seizure localisation and treatment. During these recordings, epilepsy patients memorised lists of words while the electrodes placed in their hippocampus and amygdala recorded the brain’s electrical activity.

Studying brain-wave patterns of emotional words

Qasim found that participants remembered more emotionally rated words, such as “dog” or “knife,” better than more neutral words, such as “chair.” Whenever participants successfully remembered emotional words, high-frequency neural activity (30-128 Hz) would become more prevalent in the amygdala-hippocampal circuit, a pattern which was absent when participants remembered more neutral words, or failed to remember a word altogether. Analysing 147 participant, they found a clear link between participants’ enhanced memory for emotional words and the prevalence in their brains of high-frequency brain waves across the amygdala-hippocampal circuit.

“Finding this pattern of brain activity linking emotions and memory was very exciting to us, because prior research has shown how important high-frequency activity in the hippocampus is to non-emotional memory,” said Jacobs. “It immediately cued us to think about the more general, causal implications – if we elicit high-frequency activity in this circuit, using therapeutic interventions, will we be able to strengthen memories at will?”

Electrical stimulation disrupts memory for emotional words

In order to establish whether this high-frequency activity actually reflected a causal mechanism, Jacobs and his team formulated a unique approach to replicate the kind of experimental disruptions typically reserved for animal research. First, they analysed a subset of these patients who had performed the memory task while direct electrical stimulation was applied to the hippocampus for half of the words that participants had to memorise. They found that electrical stimulation, which has a mixed history of either benefiting or diminishing memory depending on its usage, clearly and consistently impaired memory specifically for emotional words.

Uma Mohan, another PhD student in Jacobs’ lab at the time and co-author on the paper, noted that this stimulation also diminished high-frequency activity in the hippocampus. This provided causal evidence that, by knocking out the brain activity pattern correlating with emotional memory, stimulation was also selectively diminishing emotional memory.

Depression acts similarly to brain stimulation

Qasim further hypothesized that depression, which can involve dysregulated emotional memory, might act similarly to brain stimulation. He analyzed patients’ emotional memory in parallel with mood assessments the patients took to characterize their psychiatric state. And, in fact, in the subset of patients with depression, the team observed a concurrent decrease in emotion-mediated memory and high-frequency activity in the hippocampus and amygdala.

“By combining stimulation, recording, and psychometric assessment, they were able to demonstrate causality to a degree that you don’t always see in studies with human brain recordings,” said Bradley Lega, a neurosurgeon and scientist at the University of Texas Southwestern Medical Center and not an author on the paper. “We know high-frequency activity is associated with neuronal firing, so these findings open new avenues of research in humans and animals about how certain stimuli engage neurons in memory circuits.”

Next steps

Qasim is now investigating how individual neurons in the human brain fire during emotional memory processes. Qasim and Jacobs hope that their work might also inspire animal research exploring how this high-frequency activity is linked to norepinephrine, a neurotransmitter linked to attentional processes that they theorise might be behind the enhanced memory for emotional stimuli. They also hope that future research will target high-frequency activity in the amygdala-hippocampal circuit to protect memory.

“Our emotional memories are one of the most critical aspects of the human experience, informing everything from our decisions to our entire personality,” Qasim added. “Any steps we can take to mitigate their loss in memory disorders or prevent their hijacking in psychiatric disorders is hugely exciting.”

Source: Columbia University School of Engineering and Applied Science.