An experimental medicine investigation of the effects of potential novel antidepressant interventions on emotion and reward related information proces

Recent attempts to reconcile neuropharmacological and cognitive accounts of depression have led to the development of a cognitive neuropsychological model of antidepressant treatment action. This model suggests that antidepressant drugs exert their clinical effects by acutely inducing positive biases in "hot" (i.e. emotion-related) cognitive processes which can counteract the negative biases in affective information processing that are inherent to depression. The validity of this model is well supported by a multitude of empirical studies investigating the effects of different established antidepressant drugs which, taken together, suggest that the induction of positive biases is a common and crucial causal mechanism of antidepressant action.
The aim of my DPhil project is to investigate whether potential novel antidepressant treatments could have similar effects. Taking an experimental medicine approach, three different interventions are studied in healthy volunteers: bright light treatment, practising positive psychology, and administration of the dopamine D2/D3 receptor-preferring agonist pramipexole. In addition to their effects on hot cognitive processes, for each of these interventions, potential effects on subjective state and, where of interest, also effects on other relevant measures (e.g. HPA axis activity for practising positive psychology, gustatory processing for pramipexole treatment) are tested. The results of this work will allow us to better understand potential cognitive effects of the three interventions and will show whether their clinical effects could be explained within the theoretical framework of the cognitive neuropsychological model of antidepressant treatment action.