Assessment of Comorbid Obsessive-Compulsive Disorder and Posttraumatic Stress Disorder

Obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD) are commonly comorbid and share prominent features (e.g., intrusions, safety behaviors, and avoidance). Excellent self-report and clinician-administered assessments exist for OCD and PTSD individually, but few assess both disorders, and even fewer provide instruction on differential diagnosis or detection of comorbid OCD and PTSD. To address this gap in the literature, the current paper aims to (1) highlight diagnostic and functional similarities and differences between OCD and PTSD to inform differential diagnosis, (2) outline assessment recommendations for individuals with suspected comorbid OCD and PTSD, OCD with a significant trauma history or posttraumatic symptoms, or PTSD with significant obsessive-compulsive symptoms, and (3) explore future directions to evaluate and improve methods for assessing co-occurring OCD and PTSD.

Frontopolar multifocal transcranial direct current stimulation reduces conditioned fear reactivity during extinction training: A pilot randomized controlled trial

Exposure-based therapies for anxiety and related disorders are believed to depend on fear extinction learning and corresponding changes in extinction circuitry. Frontopolar multifocal transcranial direct current stimulation (tDCS) has been shown to improve therapeutic safety learning during in vivo exposure and may modulate functional connectivity of networks implicated in fear processing and inhibition. A pilot randomized controlled trial was completed to determine the effects of frontopolar tDCS on extinction learning and memory. Community volunteers (n = 35) completed a 3-day fear extinction paradigm with measurement of electrodermal activity. Participants were randomized (single-blind) to 20-min of sham (n = 17, 30 s. ramp in/out) or active (n = 18) frontopolar (anode over Fpz, 10-10 EEG) multifocal tDCS (20-min, 1.5 mA) prior to extinction training. Mixed ANOVAs revealed a significant group*trial effect on skin conductance response (SCR) to the conditioned stimulus (CS + ) during extinction training (p = 0.007, Cohen's d = 0.55). The effects of frontopolar tDCS were greatest during the first two extinction trials, suggesting that tDCS may have promoted fear inhibition prior to safety learning. Return of fear to the CS + during tests were comparable across conditions (ps > 0.50). These findings suggest that frontopolar tDCS may modulate the processing of threat cues and associated circuitry or promote the inhibition of fear. This has clear implications for the treatment of anxiety and related disorders with therapeutic exposure.