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.

See what’s going on at NeuRA

FEEL THE BUZZ IN THE AIR? US TOO.

Exploring the electrophysiology and heritability of wellbeing and resilience

The majority of adults without a mental illness still experience poor mental health, indicating a need for a better understanding of what separates mental wellness from mental illness. One way of exploring what separates those with good mental health from those with poor mental health is to use electroencephalography (EEG) to explore differences in brain activity within the healthy population. Previous research has shown that EEG measures differ between clinical groups and healthy participants, suggesting that these measures are useful indicators of mental functioning. Miranda Chilver’s current project aims to examine how different EEG measures relate to each other and to test if they can be used to predict mental wellbeing. Furthermore, she hopes to distinguish between EEG markers of symptoms including depression and anxiety, and markers of positive symptoms of wellbeing to better understand how wellbeing can exist independently of mental illness. This will be done by obtaining measures of wellbeing and depression and anxiety symptoms using the COMPAS-W and DASS-42 questionnaires, respectively. Because EEG measures and mental wellbeing are both impacted by genetics as well as the environment, Miranda will also be testing whether the links found between EEG activity and Wellbeing are driven primarily by heritable or by environmental factors. This information will inform the development of future interventions that will aim to improve wellbeing in the general population. To achieve these goals, the project will assess the relationship between EEG activity and wellbeing, and between EEG and depression and anxiety symptoms to first test whether there is an association between EEG and mental health. Second, the heritability of the EEG, wellbeing, depression, and anxiety will be assessed to determine the extent to which these variables are explained through heritable or environmental factors. Finally, a model assessing the overlap between the heritable versus environmental contributions to each measure will be developed to assess whether genetics or environment drive the relationship between EEG and mental health. This project is based on a sample of over 400 healthy adult twins from the Australian TWIN-E study of resilience led by Dr Justine Gatt. This research will pave the way for improved mental health interventions based on individual needs.
PROJECT