Stimulation of Parieto-hippocampal Connectivity in Patients With Major Depressive Disorder

Stimulation of Parieto-hippocampal Connectivity in Patients With Major Depressive Disorder

This study aims to investigate the effects of individualized repetitive transcranial magnetic stimulation (rTMS) of parieto-hippocampal functional connectivity in patients with major depressive disorder (MDD). Specifically, patients will be randomized to one of three groups and will receive 15 days of rTMS over three weeks. Each day they will receive one active session of rTMS over the dorsolateral parietal cortex (DLPFC) and depending on group assignment another session either A) active rTMS over DLPFC, B) active rTMS over left and right lateral parietal cortex (LPC), or C) sham rTMS over DLPFC or LPC. Stimulation targets in the LPC will be individualized for each patient based on their resting-state functional connectivity between the hippocampus and LPC. Clinical, neuropsychological and fMRI data will be acquired before and after the treatment course.

Inclusion Criteria:

• fulfilled criteria for unipolar major depressive disorder for at least four weeks
• did not respond to a minimum of one or did not tolerate a minimum of two antidepressants in the current episode

Exclusion Criteria:

• metal in the brain or the skull
• cardiac pacemaker or intracardiac lines
• medication infusion devices
• heart or brain surgery
• pregnancy
• substance induced depression
• history of substance abuse
• psychotic episodes
• bipolar disorder
• anorexia
• posttraumatic stress disorder (current or within the last 12 months)
• claustrophobia
• any condition resulting in increased intracranial pressure
• traumatic brain injury
• history of epilepsy
• cerebral aneurysms
• dementia
• Morbus Parkinson
• Chorea Huntington
• multiple sclerosis
• stroke or transient ischemic attack (within the last 2 years)
• previous antidepressive treatment with rTMS, electroconvulsive therapy (within the last 3 months), vagus nerve stimulation or deep brain stimulation