Brain structure link to suicide

A study has established a link between brain structure and the risk of attempts by people with ­depression to take their own lives.

QIMR Berghofer Medical Research Institute’s Miguel Renteria.

An international study has established a link between brain structure and the risk of attempts by people with ­depression to take their own lives in a finding that could pave the way for treatments to prevent suicide.

Scientists studied the brains of almost 19,000 people, including 694 people who had attempted suicide and more than 6000 people with depression who had not attempted suicide, contrasting their results with those in the study who had never experienced mental health problems.

They found that in those who had attempted suicide, three regions of the brain were smaller. Those who had attempted suicide had a smaller thalamus, the “gateway” to the brain which connects brain circuits. They also were found to have a smaller right pallidum, a region that is associated with processing sensory signals and emotions. In addition, those who had attempted suicide had a lower surface area of the left ­inferior parietal lobe.

Senior researcher Miguel Rentería from Queensland’s QIMR Berghofer Medical ­Research Institute which was involved in the study, said there was no difference in the size of these sections of the brain in the two groups studied which had no history of suicide attempts.

“The most significant difference was in the size of the thalamus – one of the brain’s processing centres for sensory signals, which has historically been viewed as a passive gateway in the brain," Dr Rentería said.

“Our research provides a better understanding of the biological basis of suicidal behaviour, and is an important first step towards developing more effective and targeted suicide prevention and intervention strategies and treatments in the future.”

The findings could pave the way for the development of novel therapies that would provide the first treatment for suicidiality. Brain stimulation treatments are already being used to treat ­depression, and if scientists were able to identify which sections of the brain were involved in higher risk for suicide, they could potentially stimulate these parts of the brain to diminish that risk.

Adrian Campos from QIMR Berghofer’s Genetic Epidemiology group, the lead researcher in the study, said further studies would take place to progress that goal. “Ideally our findings can some day translate to allowing us to understand who is at a higher risk for suicidiality by performing a brain scan that would identify a brain-based genetic risk,” he said.

“These basic findings will some day enable us to come up with novel therapies, similar to therapies for depression where what we’re seeing is you identify the brain circuits that seem to be firing in a different pattern, then you use a non-invasive brain stimulation to reverse those the abnormal firing patterns.”

Study senior co-author Lianne Schmaal, head of the Mood & Anxiety Disorders Research Program at Orygen and Centre for Youth Mental Health at the University of Melbourne, said the project was the largest and most comprehensive neuroimaging study of suicide attempt to date.

If you or someone you know is at risk of suicide, call Lifeline (13 11 14) or the Suicide Call Back Service (1300 659 467), or see a doctor.