Cognitive and neural mechanisms of credit assignment

Cognitive theories of depression have proposed that depression is caused by negative attributional styles. Yet, we still lack an understanding how attributional styles arise and are maintained in the healthy and depressed population. I propose to investigate the underlying cognitive and neural mechanisms of credit assignment, i.e. learning about the causes of events. For this, I will develop a novel behavioural paradigm. In this new task, participants will play several 'mini games' together with another player. The participants' task is to infer across trials how well they and the other player perform. This paradigm will allow me to investigate how people learn about the causes of positive and negative events in a social context. I will employ this paradigm in four studies: a large online study, an fMRI and an EEG study with healthy participants and an fMRI or EEG study with depressed participants. This set of studies will allow me, first, to develop computational models quantifying how people attribute outcomes, then to find the brain regions involved in credit assignment to the self or others, and, finally, how this process evolves over time. I will then test how these neural mechanisms in the healthy brain differ in depressed participants. To increase the transparency of the project, I will preregister all hypotheses and analyses on the open science framework (osf.io). Taken together, I aim to gain an understanding of the cognitive and neural mechanisms of credit assignment. In the future, this will be necessary to develop new treatments (e.g. non-invasive brain stimulation) for depression.