Twins hold the key to protecting ourselves against mental illness

Researchers at Neuroscience Research Australia (NeuRA) are studying hundreds of twins to identify whether resilience against mental health disorders is primarily determined by our genes or our environment.

The study of 260 identical and nonidentical twins involves comparing and contrasting their mental wellbeing and brain structure and function over a 10-year period.

“No one knows whether people have certain genes that make them intrinsically more resilient to mental illness over time, or whether it is someone’s life experiences that helps protect them from disorders such as depression or anxiety disorder,” said NeuRA Senior Research Scientist and UNSW Senior Research Fellow, Dr Justine Gatt.

“Given the known genetic differences between identical twins and non-identical twins, we are able to use this information to model how changes in mental wellbeing and changes in the brain are determined by genetic factors or their environments – or both. This will help us understand the underlying mechanisms that impact our mental state and how we can maintain optimal mental health despite the stressors we can all experience,” she said.

The 260 twins were also part of a larger mental health study, in which Dr Gatt and colleagues investigated the emotional and cognitive functioning of 1,600 twins 10 years ago.  This study found that both genes and environment impact a person’s mental wellbeing, but researchers are yet to determine how this changes over long periods of time.

“We are analysing their mental wellbeing over the past decade to identify what are the key factors that will predict the twins to be more resilient or susceptible to mental illness,” Dr Gatt said.

“The findings of this study could allow clinicians to create more effective and individualised approaches to prevent and treat debilitating mental illnesses.”

Through her research on twins, Dr Gatt has developed the COMPAS-W composite wellbeing scale, which measures wellbeing in its totality by encompassing both subjective (hedonia) and psychological (eudaimonia) factors. The 26-item COMPAS-W Wellbeing Scale can also be used to calculate measures of composure, own-worth, mastery, positivity, achievement and satisfaction.

Her research on the 1,600 twins has also found:

  • Almost half (48%) of an individual’s wellbeing is determined by genetics. The remainder is accounted for by our environment.
  • Higher wellbeing is associated with lower depression and anxiety, improved attention and working memory, and quicker reaction times to happy facial expressions.
  • People with higher wellbeing tend to have improved cognitive and emotional function.


Wellbeing refers to our state of mental wellness; that is, our levels of life satisfaction, positive and negative affective states and psychological wellbeing, at any given point in time.

Whereas resilience refers to the process of adaptive recovery to one’s optimal mental state, following adversity of trauma exposure.