Another series of studies has reported that fMRI-based neurofeedback targeted at orbitofrontal regions in which activity was correlated with contamination anxiety in individuals without psychiatric diagnoses but with high trait scores of contamination obsessions and washing compulsions resulted in significantly reduced connectivity between the orbitofrontal regions and other limbic areas, including the amygdala, as well as significantly increased connectivity in prefrontal regions associated with emotion regulation, including right lateral PFC [64]. Importantly, self-report anxiety ratings while viewing contamination-provoking stimuli were also significantly reduced several days following fMRI-neurofeedback [64]. Furthermore, this fMRI-neurofeedback protocol resulted in a 20% decrease in OCD symptom severity in a small sample (n=5) of patients with contamination-related OCD [65]. Although not tested in patients with OCD, fMRI-neurofeedback targeting regulation of amygdala activity was effective in reducing amygdala activity and increasing amygdala-vmPFC functional connectivity in non-psychiatric participants [66]. Further investigation of non-invasive neuromodulatory interventions targeting fronto-limbic circuitry is warranted in OCD.
