Abstract
Aversive events are sometimes re-experienced as intrusive memories – i.e., involuntary and spontaneous retrievals of the aversive memory accompanied by significant distress. Intrusive memories are predominantly visual, and previous results suggest that the vividness of mental images is coupled with elevated visual cortex activity. Here, we tested whether neuromodulation of visual cortex following encoding of a “trauma” film could reduce the frequency and intensity of subsequent memory intrusions. Participants viewed a “trauma” film and were then requested to record each intrusive memory of the film during the ensuing 5 days. Leveraging memory reactivation frameworks according to which reactivation of an existing memory may enable its modification, one day following the trauma film watching participants’ memory of the film was reactivated by brief reminders, followed by 15 minutes of inhibitory 1Hz repetitive Transcranial Magnetic Stimulation (rTMS) over the visual cortex (visual-rTMS, n=19) or over a control site (vertex, n=21). Results indicate that visual-rTMS reduced the intensity of distress caused by memory intrusions. In addition, functional connectivity between visual and emotional resting-state brain networks measured using fMRI prior to film viewing suggests that interactions between visual and emotional processing areas determine the distress intensity of intrusive memories. Together, these findings point to potential neuroscience-driven interventions designed to downregulate the distress experienced by intrusive memories.