Effects of self-evaluation on the P300 event-related potential

The effects of self evaluation on the P300 event-related potential (ERP) were explored with 56 participants (16 men, 40 women; M age = 23.4 yr., SD = 1.2) across three conditions. The conditions included (1) a standard ERP auditory oddball discrimination between a random target (15% occurrence) and standard stimuli (85% occurrence), (2) the oddball task followed by the additional cognitive task of maintaining a mental count of the target tones, and (3) the oddball task followed by the additional cognitive task of self-evaluating whether they felt surprised by the current occurrence of the target tone. The added cognitive requirements for Conditions 2 and 3 required the subjects to maintain a cognitive readiness for the secondary stimulus-related task during their sensory discrimination response for the standard oddball task. During the self-evaluation condition, the P300 amplitude was significantly larger across all recording locations than the regular oddball condition and the cognitive count condition.     

Therapist Behavior During Exposure Tasks Predicts Habituation and Clinical Outcome in Three Randomized Controlled Trials for Pediatric OCD

This study measured therapist behaviors in relation to subsequent habituation within exposure tasks, and also tested their direct and indirect relationships (via habituation) with clinical outcomes of exposure therapy. We observed 459 videotaped exposure tasks with 111 participants in three clinical trials for pediatric obsessive-compulsive disorder (POTS trials). Within exposure tasks, therapist behaviors and patient fear were coded continuously. Outcomes were habituation and posttreatment change in symptom severity, global improvement, and treatment response. More therapist behaviors that encourage approach—and less use of accommodation, unrelated talk, and externalizing language—predicted greater subsequent habituation during individual exposure tasks (exposure-level), and also predicted improved patient clinical outcomes via higher “total dose” of habituation across treatment (patient-level indirect effect). For six of seven therapist behaviors analyzed, the relationship with subsequent habituation within exposure differed by patient fear (low, moderate, or high) at the time the behavior was used. Two therapist behaviors had direct effects in the opposite direction expected; more unrelated talk and less intensifying were associated with greater patient symptom reduction. Results shed light on the “black box” of in-session exposure activities and point to specific therapist behaviors that may be important for clinical outcomes. These behaviors might be best understood in the context of changing patient fear during exposure tasks. Future studies should test whether therapist behaviors can be experimentally manipulated to produce improvement in clinical outcomes.