Conditions: Major Depressive Disorder (MDD)
Keywords: MDD Major Depressive Disorder Amisulpride
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 159
Healthy volunteers: yes

Brief summary:
The purpose of this study is to evaluate the effects of a single low dose of the D2/D3 antagonist amisulpride on reward processing. More generally, this study will test the role of dopamine (a naturally occurring brain chemical) in depression.

Hypotheses:

Administration of a single low dose of the D2/D3 antagonist amisulpride will (1) improve performance in a behavioral task assessing learning from feedback and (2) boost activation in reward-related brain regions.

Detailed description:
Through an integration of a functional magnetic resonance imaging (fMRI) approach coupled with a pharmacological challenge, the goal of the current study will be to investigate the role of dopamine in MDD. Participants in this research will include 36 MDD subjects and 36 demographically matched healthy participants recruited from the community by Dr. Pizzagalli's laboratory at McLean Hospital's Center for Depression, Anxiety and Stress Research. This study will include two sessions:

* The first session will involve a diagnostic interview, and a series of questionnaires and assessments.
* The second session will take place at the McLean Hospital's Neuroimaging Center, and include the administration of a low-dose of amisulpride (50 mg capsule) or placebo, followed by an fMRI brain scan and administration of two behavioral tasks.

Arms:
arm 1: Subjects experiencing a current episode of major depression who are randomized to receive amisulpride arm 2: Subjects experiencing a current episode of major depression who are randomized to receive placebo arm 3: Subjects having no history of mental disorder (healthy controls, HC) who are randomized to receive amisulpride arm 4: Subjects having no history of mental disorder who are randomized to receive placebo

Interventions: intervention 1: amisulpride intervention 2: placebo
Intervention descriptions: intervention 1: single low-dose pharmacological challenge, 50 mg amisulpride intervention 2: single-dose placebo capsule

Protocol document: