NeuRA Magazine #20

CHILDHOOD TRAUMA AND PSYCHOSIS

Understanding the various causes of psychosis is a key way to improve treatments. Dr Yann Quidé is using fMRI to understand how childhood trauma may change the brain of a person who has experienced psychosis.

Dr Yann Quidé

There is increasing evidence that exposure to childhood trauma is a risk factor for some psychiatric conditions, including post-traumatic stress disorder, depression, anxiety and psychotic disorders. Trauma may present a different pathway to illness compared to those who have a psychiatric condition but who did not experience childhood trauma, and so may require a different treatment approach.

Within the Imaging Genetics in Psychosis project, lead by Assoc Prof Melissa Green, around 60 percent of psychosis patients and around 40 percent of healthy participants were exposed to significant levels of childhood trauma. This includes emotional and physical abuse, neglect and sexual abuse. Interestingly, there is a significant overlap between the cognitive domains that are usually affected in psychotic disorders, and those reported in (non-psychotic) psychiatric and non-psychiatric populations exposed to childhood trauma. The overlap appears to include executive functions, working memory and social cognition.

To identify these trauma-related brain abnormalities in psychosis, participants underwent functional magnetic resonance imaging (fMRI) while performing tasks that use the previously mentioned overlapping cognitive domains. Results indicated that being exposed to trauma was associated with inefficient activation of key brain regions for working memory in psychosis patients.

The study, led by Dr Yann Quidé, also found that some people with schizophrenia or schizoaffective disorder who experienced childhood trauma present abnormal patterns of brain function in regions important to understanding another person’s mental state, also called theory-of-mind. These findings confirm that trauma-exposure leads to distinct brain abnormalities in psychosis, and may help to improve personalised approaches to treatment of psychosis.

However, childhood trauma exposure also sets off a cascade of other biological processes that influence the pathway to illness. These include the stress system, otherwise known as the HPA (hypothalamic pituitary adrenal) axis; pro-inflammatory immune responses; or neuronal growth and differentiation. Modifications of these biological markers can lead to the physiological changes in brain structure or function, as we observed.

Dr Yann Quidé recently received an 2016 Early-Career Project Grant award from the Society for Mental Health Research (SMHR) in order to further investigate the associations between these biological dysfunctions, trauma-exposure and psychosis.

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