title: Are neuroticism and extraversion associated with the antidepressant effects of repetitive transcranial magnetic stimulation (rTMS)? An exploratory 4-week trial.
abstract: Several randomized, controlled trials have found high frequency repetitive transcranial magnetic stimulation (HF-rTMS) to be effective for treating major depressive disorder (MDD), but its antidepressant mechanisms have yet to be firmly understood. In this context, pre-treatment personality traits and subsequent changes in personality concomitant to treatment may be relevant for our understanding of these mechanisms. To investigate this issue we conducted a naturalistic trial in which 14 subjects with moderate to severe depression were treated with daily HF-rTMS over the left dorsolateral prefrontal cortex for 4 weeks. Objective depressive symptoms (as assessed by the HAM-D(21)) and the major personality dimensions of neuroticism and extraversion were measured pre-post HF-rTMS. Pre-rTMS levels of extraversion predicted subsequent decrease in depressive symptoms. Also, HF-rTMS treatment resulted in a decrease in neuroticism scores, and this relative decrease was associated with the relative decrease in depression. Our results suggest that HF-rTMS may positively affect the personality dimension of neuroticism. Also, pre-treatment levels of extraversion may predict the subsequent antidepressant response to HF-rTMS. However, further studies with larger samples and controlled designs are needed to better clarify these preliminary findings.
authors.affiliation: Depressive Disorders Program, Douglas Mental Health University Institute and McGill University, Montréal, Québec, Canada. nrc.douglas@me.com
authors.forename: Marcelo T
authors.initials: MT
authors.lastname: Berlim
authors.forename: Alexander
authors.initials: A
authors.lastname: McGirr
authors.forename: Marie-Martine
authors.initials: MM
authors.lastname: Beaulieu
authors.forename: Frederique
authors.initials: F
authors.lastname: Van den Eynde
authors.forename: Gustavo
authors.initials: G
authors.lastname: Turecki
mesh_terms: D000328:Adult; D001008:Anxiety Disorders / Q000523:psychology*; D003863:Depression / Q000523:psychology / Q000628:therapy*; D005120:Extraversion, Psychological; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000075384:Neuroticism; D050781:Transcranial Magnetic Stimulation