Modulating functional connectivity between medial frontopolar cortex and amygdala by inhibitory and excitatory transcranial magnetic stimulation.
The prefrontal-limbic network in the human brain plays a major role in social cognition, especially cognitive control of emotion. The medial frontopolar cortex (mFP; Brodmann Area 10) and the amygdala are part of this network and display correlated neuronal activity in time, as measured by functional magnetic resonance imaging (fMRI). This functional connectivity is dynamic, sensitive to training, and affected in mental disorders. However, the effects of neurostimulation on functional connectivity within this network have not yet been systematically investigated. Here, we investigate the effects of both low- and high-frequency repetitive transcranial magnetic stimulation (rTMS) to the right mFP on functional connectivity between mFP and amygdala, as measured with resting state fMRI (rsfMRI). Three groups of healthy participants received either low-frequency rTMS (1 Hz; N = 18), sham TMS (1 Hz, subthreshold; N = 18) or high-frequency rTMS (20 Hz; N = 19). rsfMRI was acquired before and after (separate days). We hypothesized a modulation of functional connectivity in opposite directions compared to sham TMS through adjustment of the stimulation frequency. Groups differed in functional connectivity between mFP and amygdala after stimulation compared to before stimulation (low-frequency: decrease, high-frequency: increase). Motion or induced changes in neuronal activity were excluded as confounders. Results show that rTMS is effective for increasing and decreasing functional coherence between prefrontal and limbic regions. This finding is relevant for social and affective neuroscience as well as novel treatment approaches in psychiatry.
['Riedel|Philipp|P|', 'Heil|Matthias|M|', 'Bender|Stephan|S|', 'Dippel|Gabriel|G|', 'Korb|Franziska M|FM|', 'Smolka|Michael N|MN|', 'Marxen|Michael|M|0000-0001-8870-0041']
D000293:Adolescent D000328:Adult D000339:Affect D000679:Amygdala D001007:Anxiety D001931:Brain Mapping D063132:Connectome D005260:Female D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D008959:Models, Neurological D008960:Models, Psychological D009434:Neural Pathways D059906:Neuroimaging D017397:Prefrontal Cortex D012016:Reference Values D057566:Self Report D050781:Transcranial Magnetic Stimulation D055815:Young Adult
functional connectivity frontopolar cortex amygdala transcranial magnetic stimulation social cognition emotion resting state MRI