Randomised, double-blind, placebo-controlled parallel study (n=60) comparing a single IV ketamine infusion (0.5 mg/kg) to saline in patients with treatment-resistant depression to assess effects on autobiographical memory, emotional and reward processing, and brain connectivity.
This randomised, double-blind, placebo-controlled parallel-group study in participants with treatment-resistant depression examines the acute effects of a single intravenous ketamine infusion (0.5 mg/kg) versus saline on autobiographical memory reconsolidation, emotional processing and reward learning, and associated brain connectivity.
Participants undergo screening, behavioural tasks, questionnaires, and an MRI scan after drug administration to measure changes in memory, emotion and network connectivity; outcomes will inform mechanisms of glutamatergic rapid-acting antidepressant effects.
Safety exclusions include active suicidality, bipolar disorder, psychosis, recent substance use disorder, pregnancy, significant cardiac or MRI contraindications; ketamine is administered for research purposes at an antidepressant dose.
Single intravenous antidepressant-dose ketamine infusion (0.5 mg/kg).
Antidepressant dose, single infusion.
Single intravenous saline infusion (0.9% sodium chloride).
Saline placebo (0.9% sodium chloride).