This interventional trial (n=120) aims to explore the neural circuit-specific mechanisms of ketamine's effect on anhedonia and anxiety in individuals with major depressive disorder (MDD).
This study examines the role of the subgenual anterior cingulate cortex (sgACC) in anhedonia and anxiety in people with MDD and measures acute and sustained effects of a single IV ketamine infusion on sgACC activation and depressive symptoms.
Randomized, parallel-group design (ketamine versus saline placebo); outcomes include neuroimaging measures of sgACC activation, clinical ratings of anhedonia and anxiety, and safety/tolerability assessments.
Single intravenous infusion of ketamine (0.5 mg/kg) in MDD and HC groups.
0.5 mg/kg ketamine dissolved in 100 mL saline, delivered intravenously.
Single intravenous normal saline infusion as placebo comparator.
Normal saline infusion (100 mL) delivered intravenously.