Increased positive emotional memory after repetitive transcranial magnetic stimulation over the orbitofrontal cortex.
OBJECTIVE
Several studies have demonstrated increased left orbitofrontal cortex (OFC) activity during negative and depressed mood. These mood states have also been associated with reduced memory for positive emotional stimuli. The aim of the present study was to investigate whether slow, inhibitory repetitive transcranial magnetic stimulation (rTMS) over the left OFC would improve memory for positive material.


METHODS
We carried out a study with a double-blind, within-subjects design, in which 12 healthy volunteers received 20 minutes of slow rTMS over the left OFC, placebo treatment over the left OFC and rTMS over the left dorsolateral portion of the prefrontal cortex. Effects on memory for fearful and happy faces were investigated.


RESULTS
Memory for happy faces was significantly improved after rTMS over the left OFC compared with placebo (t10 = 2.4, p = 0.037).


CONCLUSIONS
These findings suggest a role of the OFC in positive emotional memory, which is in accordance with neuroimaging and neuropsychological data. It may be argued that dense projections from the OFC to the limbic emotional circuit are involved in emotional memory and, therefore, play a role in the effects of rTMS that we observed.
Department of Psychonomics, Affective Neuroscience Section, Helmholtz Research Institute, Utrecht University, Utrecht, The Netherlands. d.schutter@fss.uu.nl
Dennis J L G
DJ
Schutter
Jack
J
van Honk
D000293:Adolescent; D000328:Adult; D000339:Affect / Q000502:physiology; D004311:Double-Blind Method; D004644:Emotions / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*; D011569:Psychiatric Status Rating Scales; D050781:Transcranial Magnetic Stimulation