Depression is now the world’s leading health problem, causing more disability than any other disease according to the World Health Organisation. Reading neuroscientist Dr Ciara McCabe tells us about her research on teenage depression – which uses chocolate to investigate the brain’s reward centres.
Depression affects twice as many young women as men, and it often starts in adolescence.
There has been an enormous global effort to treat depression with antidepressant drugs and psychological interventions – but these treatments don’t always work.
We think treatments and prevention strategies could be improved if we understood more about how the brain is involved in symptoms of depression.
Less pleasure in life
In our lab, the Neuroimaging of Reward Group, we are interested in understanding more about one of the main symptoms of depression: anhedonia. This is described as impaired interest and pleasure during depression.
We, and others, have shown that in adults this symptom is also related to lower levels of brain activity in response to reward. We have also focused our attention on reduced reaction to reward in the brain of adolescents with anhedonia.
The expectant brain
To activate the brain’s response to reward we use food stimuli, for example pictures or tastes of chocolate. By asking trial volunteers to do this type of task, we can examine how the anticipation or consummation of reward is represented in the brain. We can then study how this differs in those with and without symptoms of depression.
We aim to use our findings on how the brain responds to reward to develop better treatments, specifically targeted at enhancing the reward experience in depression.
Furthermore, we want to be able to predict anhedonia in adolescents who might be at greatest risk for developing clinical depression in future. We may then be able to prevent it happening by specifically targeting the brain’s reward response.