Personality Traits Linked to Differences in Brain Structure

Researchers report on how differences in cortical anatomy relates to each of the five factors of personality.

Our personality may be shaped by how our brain works, but in fact the shape of our brain can itself provide surprising clues about how we behave – and our risk of developing mental health disorders – suggests a study published today.

According to psychologists, the extraordinary variety of human personality can be broken down into the so-called ‘Big Five’ personality traits, namely neuroticism (how moody a person is), extraversion (how enthusiastic a person is), openness (how open-minded a person is), agreeableness (a measure of altruism), and conscientiousness (a measure of self-control).

In a study published today in the journal Social Cognitive and Affective Neuroscience, an international team of researchers from the UK, US, and Italy have analyzed a brain imaging dataset from over 500 individuals that has been made publicly available by the Human Connectome Project, a major US initiative funded by the National Institutes of Health. In particular, the researchers looked at differences in the brain cortical anatomy (the structure of the outer layer of the brain) as indexed by three measures – the thickness, area, and amount of folding in the cortex – and how these measures related to the Big Five personality traits.


The researchers looked at differences in the brain cortical anatomy (the structure of the outer layer of the brain) as indexed by three measures – the thickness, area, and amount of folding in the cortex – and how these measures related to the Big Five personality traits. NeuroscienceNews.com image is adapted from the University of Cambridge press release.

“Evolution has shaped our brain anatomy in a way that maximizes its area and folding at the expense of reduced thickness of the cortex,” explains Dr. Luca Passamonti from the Department of Clinical Neurosciences at the University of Cambridge. “It’s like stretching and folding a rubber sheet – this increases the surface area, but at the same time the sheet itself becomes thinner. We refer to this as the cortical stretching hypothesis”.

“Cortical stretching is a key evolutionary mechanism that enabled human brains to expand rapidly while still fitting into our skulls, which grew at a slower rate than the brain,” adds Professor Antonio Terracciano from the Department of Geriatrics at the Florida State University. “Interestingly, this same process occurs as we develop and grow in the womb and throughout childhood, adolescence, and into adulthood: the thickness of the cortex tends to decrease while the area and folding increase.”
In addition, as we get older, neuroticism goes down – we become better at handling emotions. At the same time, conscientiousness and agreeableness go up – we become progressively more responsible and less antagonistic.

The researchers found that high levels of neuroticism, which may predispose people to develop neuropsychiatric disorders, were associated with increased thickness as well as reduced area and folding in some regions of the cortex such as the prefrontal-temporal cortices at the front of the brain.


The researchers found that high levels of neuroticism, which may predispose people to develop neuropsychiatric disorders, were associated with increased thickness as well as reduced area and folding in some regions of the cortex such as the prefrontal-temporal cortices at the front of the brain. Credit: The researchers/University of Cambridge.

In contrast, openness, which is a personality trait linked with curiosity, creativity and a preference for variety and novelty, was associated with the opposite pattern, reduced thickness and an increase in area and folding in some prefrontal cortices.
“Our work supports the notion that personality is, to some degree, associated with brain maturation, a developmental process that is strongly influenced by genetic factors,” says Dr. Roberta Riccelli from Italy.

“Of course, we are continually shaped by our experiences and environment, but the fact that we see clear differences in brain structure which are linked with differences in personality traits suggests that there will almost certainly be an element of genetics involved,” says Professor Nicola Toschi from the University ‘Tor Vergata’ in Rome. “This is also in keeping with the notion that differences in personality traits can be detected early on during development, for example in toddlers or infants.”

The volunteers whose brains were imaged as part of the Human Connectome Project were all healthy individuals aged between 22 and 36 years with no history of neuro-psychiatric or other major medical problems. However, the relationship between differences in brain structure and personality traits in these people suggests that the differences may be even more pronounced in people who are more likely to experience neuro-psychiatric illnesses.

“Linking how brain structure is related to basic personality traits is a crucial step to improving our understanding of the link between the brain morphology and particular mood, cognitive, or behavioral disorders,” adds Dr. Passamonti. “We also need to have a better understanding of the relation between brain structure and function in healthy people to figure out what is different in people with neuropsychiatric disorders.”
This is not the first time the researchers have found links between our brain structure and behavior. A study published by the group last year found that the brains of teenagers with serious antisocial behavior problems differ significantly in structure to those of their peers.

Source: University of Cambridge.

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The Wonderful Maths: Will Improves our Emotional Health?

According to researchers, engaging the prefrontal cortex with mental math exercises could help to improve emotional health.

Engaging a specific part of the brain during mental math exercises is connected with better emotional health, according to a new brain-scanning study published by Duke researchers in the journal Clinical Psychological Science.

The research takes a preliminary step toward informing new brain training strategies to stave off depression and anxiety. Although the relationship between math and emotion needs further study, the new findings may also lead to new tests gauging the effectiveness of psychological therapies.

“Our work provides the first direct evidence that the ability to regulate emotions like fear and anger reflects the brain’s ability to make numerical calculations in real time,” said Matthew Scult, a neuroscience graduate student in the lab of the study’s senior investigator Ahmad Hariri, a professor of psychology and neuroscience at Duke.



An overlay of an MRI shows the parts of the brain that are engaged in doing cold calculations and dealing with hot emotions. New research from Duke shows that mental math in this part of the brain may aid emotional health. NeuroscienceNews.com image is credited to Annchen R. Knodt.

Although they may seem unrelated, doing “cold” calculations and regulating “hot” emotions both rely on similar mental gymnastics: the ability to manipulate and update information. Researchers have long speculated about the link between the two. In the new study, Hariri’s group analyzed brain activity of 186 undergraduates — using a type of non-invasive brain scan called functional magnetic resonance imaging — while they were doing math problems from memory.



The students are participants in the ongoing Duke Neurogenetics Study, which is exploring relationships between genes, the brain and mental health. In addition to the scans, participants completed questionnaires and interviews assessing their mental health status and emotional coping strategies.

Memory-based math problems stimulate a region of the brain called the dorsolateral prefrontal cortex, which has already been linked to depression and anxiety. Studies have found, for example, that higher activity in this area is associated with fewer symptoms of anxiety and depression. A well-established psychological treatment called cognitive behavioral therapy, which teaches individuals how to re-think negative situations, has also been seen to boost activity in the dorsolateral prefrontal cortex. In the current study, the more active a person’s dorsolateral prefrontal cortex was while performing mental math, the more likely he or she was to report being able to adapt their thoughts about emotionally difficult situations.

“We don’t know for sure why that is, but it fit into our hypothesis that the ability to do these more complex math problems might allow you to more readily learn how to think about complex emotional situations in different ways,” Scult said. “It is easy to get stuck in one way of thinking.” Greater activity in the dorsolateral prefrontal cortex also was associated with fewer depression and anxiety symptoms. The difference was especially obvious in people who had been through recent life stressors, such as failing a class.



Participants with higher dorsolateral prefrontal activity were also less likely to have a mental illness diagnosis. It is still unclear whether more actively engaging the brain area with math exercises would lead to better emotional coping strategies or the other way around. The researchers plan to collect the same type of data over a longer time period, to see whether one observation precedes the other. “We hope, with these and future studies, that we can inform new strategies to help people regulate their emotions, and to prevent symptoms of anxiety and depression from developing in the first place,” Scult said.

Source: Karl Bates – Duke Image Source: NeuroscienceNews.com image is credited to Annchen R. Knodt. Original Research: Abstract for “Thinking and Feeling: Individual Differences in Habitual Emotion Regulation and Stress-Related Mood Are Associated With Prefrontal Executive Control” by Matthew A. Scult, Annchen R. Knodt, Johnna R. Swartz, Bartholomew D. Brigidi
and Ahmad R. Hariri in Clinical Psychological Science. Published online October 6 2016 doi:10.1177/2167702616654688. Neurosciencenews

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Fish oil: A miracle for the brain

Eating more fish or taking regular fish oil supplements may help prevent psychosis in those most at risk, researchers claim.

A three month course of daily fish oil capsules appeared to significantly reduce the rate of psychotic disorders in young people, an improvement that seemed to persist when doctors assessed their mental health seven years later.

But while the findings are intriguing, they come from a very small study of teenagers and young adults. The benefits must now be shown in a much larger group before doctors can make any recommendations about the use of fish oils to prevent mental health problems.

Paul Amminger at the University of Melbourne reported in 2010 that a three month course of daily fish oil capsules appeared to stave off psychotic illnesses in teenagers and young adults aged 13 to 24 deemed at high risk of developing the disorders. Seven years on, his group has now revisited 71 of the original 81 participants and shown that the protective effects seem to persist.

Writing in the journal Nature Communications, the scientists report that 4 out of 41 of those who took fish oil for three months had developed psychosis in the seven years since, compared with 16 out of 40 who received a placebo capsule during the trial.

Those on the placebo wing of the trial appeared to develop psychosis more quickly than those taking fish oils, and had an overall greater likelihood of having other psychiatric disorders, the study found.

Schizophrenia is one of the most common serious mental health conditions. One in 100 people in Britain experience symptoms, such as delusions, visual or auditory hallucinations, in their lifetimes, and many continue to lead normal lives. It is most often diagnosed between the ages of 15 and 35. It is called a psychotic illness, and those affected sometimes cannot distinguish between their thoughts and reality.

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“Schizophrenia is a major cause of disability, but early treatment has been linked to better outcomes. Our study gives hope that there may be alternatives to antipsychotic medication,” Amminger told the Guardian.

He believes that omega-3 polyunsaturated fatty acids (PUFAs) could be a stigma-free and long-term way to prevent psychosis in young people who are most at risk, with minimal side effects.

Omega-3 fatty acids are essential for healthy brain development and function, and a lack of them in the diet has been linked to various mental health conditions. “Eating more fish is not only likely to be good for your physical health but also for your mental health,” Amminger said.

In 2006, scientists working for the Cochrane collaboration reviewed the published research on the potential for fish oils to prevent schizophrenia and declared the results inconclusive. They went on to call for larger studies with more patients. Amminger agreed that his latest findings need to be replicated in larger groups opf people before any firm guidance can be given.

Clive Adams, co-ordinating editor of the Cochrane Schizophrenia Group at Nottingham University said the study needed to be considered alongside other published trials on the effects of omega-3 oils, but added that it was a springboard for new trials on the treatments. “The road of treatment of people with schizophrenia is paved with many good intentions and false dawns. This study is important, undertaken by leaders in the field, but it does not provide strong enough proof to really change practice,” he said.

http://www.theguardian.com/science/2015/aug/11/fish-oil-could-help-prevent-mental-health-problems-psychosis?CMP=share_btn_link
Photograph: Graham Turner