AUTHOR=Guhn Anne , Dresler Thomas , Andreatta Marta , Müller Laura D., Hahn Tim , Tupak Sara V., Polak Thomas , Deckert Jürgen , Herrmann Martin J.
TITLE=Medial prefrontal cortex stimulation modulates the processing of conditioned fear
JOURNAL=Frontiers in Behavioral Neuroscience
VOLUME=Volume 8 - 2014
YEAR=2014
URL=https://www.frontiersin.org/journals/behavioral-neuroscience/articles/10.3389/fnbeh.2014.00044
DOI=10.3389/fnbeh.2014.00044
ISSN=1662-5153
ABSTRACT=The extinction of conditioned fear is dependent on an efficient interplay between the amygdala and the medial prefrontal cortex (mPFC). In rats, high-frequency electrical mPFC stimulation was shown to improve extinction by a reduction of amygdala activity. However, so far it is unclear whether stimulation of homologues regions in humans might have similar beneficial effects.
Healthy volunteers received one-session of either active or sham repetitive transcranial magnetic stimulation (rTMS) covering the mPFC while undergoing a two-day fear conditioning and extinction paradigm. rTMS was applied offline after fear acquisition in which one of two faces (CS+ but not CS-) was associated with an aversive scream (UCS). Immediate extinction learning (day 1) and extinction recall (day 2) were conducted without UCS delivery. Conditioned responses were assessed in a multimodal approach using fear-potentiated startle (FPS), skin conductance responses (SCR), functional near-infrared spectroscopy (fNIRS) and self-report scales.
Consistent with the hypothesis of a modulated processing of conditioned fear after high-frequency rTMS, the active group showed a reduced CS+/CS- discrimination during extinction learning as evident in FPS as well as in SCR and arousal ratings. FPS responses to CS+ further showed a linear decrement throughout both extinction sessions. This study describes the first experimental approach of influencing conditioned fear by using rTMS which can be a basis for future studies investigating a complementation of mPFC stimulation to cognitive behavioral therapy.