Brains of young people with suicidal thoughts and behaviours look different: study

Brains of young people with suicidal thoughts and behaviours look different: study

19 October 2022

The brains of young people who have suicidal thoughts and behaviours look structurally slightly different from those who don’t, a recent international consortium study led by Orygen’s Associate Professor Lianne Schmaal has found.

The paper found that the surface area of the brain’s frontal pole was lower in young people with a history of suicide attempts and mood disorders such as anxiety, depression and bipolar disorder.

“The frontal pole is the part of the brain that is associated with higher-order functions involved in emotion and other behavioural regulation, such as decision-making, cognitive inhibition and relating information about the world to oneself,” paper senior author Associate Professor Schmaal said.

“When we talk about the surface area of the frontal pole being ‘lower’ what we mean is that there are differences in the size of this brain region.”

The study found that while the difference in size was subtle, it was potentially important.

“Most young people with a history of a suicide attempt have brains that are not very different from people without a history of suicide attempt, which is reassuring,” Associate Professor Schmaal said.

“However, the subtle differences that we found do provide us with a better understanding of the mechanisms involved in suicidal behaviours and may eventually provide important targets for suicide prevention strategies.”  

Published in Molecular Psychiatry, the paper was co-authored by 78 mental health experts from around the world working together within the ENIGMA Suicidal Thoughts and Behaviours consortium.

The mega-analysis included magnetic resonance imaging (MRI) data from 21 international studies relating to young people aged 8–25.

“This is the first time that a very large international team of neuroscientists, psychologists and psychiatrists have made joint efforts to pool together the amount of data this type of study requires,” Associate Professor Schmaal said.

“Suicidal behaviours occur across many mental illnesses, so instead of focusing on a single illness in small samples, we pulled together and compared data on suicidal behaviours across mental disorders. We specifically focused on youth, given that suicide is the leading cause of death in young people in Australia, yet very little neuroimaging research has focused on this age group until now.”

While the findings are promising, they require further investigation.

“While lower frontal pole surface area may represent greater vulnerability for suicide attempt, we need to do more research to understand the relationship between lower surface area and suicide risk,” Associate Professor Schmaal said.

“What we need to do next is investigate how these subtle brain changes could potentially contribute to higher suicide risk, but also how this interacts with many other social, psychological and cognitive risk factors. These subtle brain differences alone cannot explain why someone has a history of suicidal behaviours; suicidal behaviours are very complex and are driven by many interacting risk factors. We need to understand these brain changes within a holistic framework of suicide risk.”

The research received Open Access funding enabled and organised by the Council of Australian University Librarians and its member institutions.