5 - (SYM 115) Changes in Hoarding Beliefs and Associated Neural Changes During a Discarding Task After Cognitive-behavioral Treatment for Hoarding Disorder

Hoarding disorder (HD) is maintained by maladaptive beliefs about possessions, and recent research has demonstrated that changes in these beliefs partially mediate improvement in cognitive-behavioral therapy (CBT) for hoarding. However, it is not yet known whether changes in neural activity, particularly when discarding possessions, are associated with cognitive change during CBT for HD.  In the present study, 58 adults with HD who completed a course of group CBT for HD participated in a discarding task before and after CBT. At baseline, 38 healthy age- and gender-matched adults completed the same task. Neural activity during the task was measured using functional magnetic resonance imaging (fMRI) as participants made simulated discarding decisions.  At baseline, activity in several frontal regions [e.g., dorsolateral prefrontal cortex (DLPFC), orbital and polar frontal cortex, inferior frontal cortex], middle insula, and posterior cingulate cortex (PCC) was significantly associated with hoarding-related beliefs in individuals with HD, rs = .27 to .45. None of these correlations were significant in the healthy comparison group. After receiving CBT for HD, decreases in maladaptive hoarding-related beliefs were associated with increased activity in the thalamus, anterior ventral insula, PCC, anterior cingulate and medial prefrontal cortex, DLPFC, and other frontal regions, as well as decreased activity in the orbitofrontal cortex rs = -.28 to -.46.  These results demonstrate that maladaptive beliefs in HD are associated with activation of specific neural regions during discarding decisions, and that reduction in beliefs over a course of CBT for HD is associated with specific changes in neural activity. Key regions implicated in belief change include several areas in the frontal and prefrontal cortices and the anterior and posterior cingulate cortex, though associations were modest in strength and will need to be replicated in future studies of this population.