Mood Brain and Development Unit - Our Research
Illustration of the identified phases of reward processing and a mapping of these onto their associated clinical and translational terminologies. The outer layer of this figure (blue) demonstrates how these phases are linked in a continuous loop. Disruption of this cycle is thought to be associated with the common depressive symptoms identified in the next layer (orange). These symptoms are studied using translational concepts (purple), which are tapped into using experimental tasks such as the Monetary Incentive Delay (MID) task, the Effort Expenditure for Rewards Task (EEfRT) and the Iowa Gambling Task (IGT) (in green).
Reward Processing and Depression
Reductions in motivation and the experience of pleasure are prominent features of depression, and many suggest they arise from aberrations in the processing of rewards. Thus, much of our research at the MBDU focuses on how people with depression respond to and work towards rewards, such as money or food. The figure below separates reward processing into four phases and maps these onto common features of depression. Typically, adolescents are more sensitive to rewards in the brain, compared to children and adults. However, many studies have found that people with depression have a weaker brain response to rewards, both in the build up to getting the reward (‘prediction’) and when actually receiving it (‘experience’). The sharp increase in depression rates in adolescence, a period associated with extensive development of the brain, makes this age a crucial target for study. Therefore, our group is using various techniques, including functional Magnetic Resonance Imaging (fMRI), electroencephalography (EEG), magnetoencephalography (MEG) and Transcranial Magnetic Stimulation (TMS) to examine the brain’s response to rewards in both adolescents and adults across a wide range of depressive symptoms.
The scan tech provides participants with instructions for completing tasks while inside the MRI scanner.
Prior to scanning, participants will get the opportunity to practice in a mock scanner that aims to imitate the experience of doing research tasks inside our MRI scanners.