August 07, 2012

A Peek into the Hoarding Brain

Brain Hubs Boil when Hoarders Face Pitching Their Own Stuff Under-Activate when Making Decisions about Others’ Possessions In patients with hoarding disorder, parts of a decision-making brain circuit under-activated when dealing with others’ possessions, but over-activated when deciding whether to keep or discard their own things, a NIMH-funded study has found. Brain scans revealed the abnormal activation in areas of the anterior cingulate cortex and insula known to process error monitoring, weighing the value of things, assessing risks, unpleasant feelings, and emotional decisions. NIMH grantee David Tolin, Ph.D., of Hartford Hospital, and colleagues, report on their functional magnetic resonance imaging (fMRI) study in the August 2012 issue of the journal Archives of General Psychiatry. Hoarding disorder, a proposed diagnosis under DSM-V, is characterized by avoidance of decision-making about possessions. The new findings pinpoint brain circuit activity suspected of underlying the lack of self-insight, indecisiveness, sense that the wrong decision is being made, inflated estimates of the desirability of objects, and exaggerated perception of risk that are often experienced with the disorder. In the study, brain activity of 43 hoarding disorder patients was compared to that of 31 obsessive compulsive disorder (OCD) patients and 33 healthy controls while they had to decide whether to keep or discard their own or others’ junk mail and newspapers. Notably, such ownership did not appear to differentially affect brain activity in the OCD patients. Hoarding disorder patients, as expected, decided to keep many more items than the other groups. The implicated brain areas are hubs of a “salience network” that weighs the emotional significance of things and regulates emotional responses and states. Hoarding patients’ severity of symptoms, self-ratings of indecisiveness, and feeling of things being “not just right” were correlated with the degree of aberrant activity in these hubs. The results add to evidence of impaired decision-making in hoarding disorder and may help to disentangle its brain workings from those of OCD and depression. Anterior cingulate cortex (center) over-activated when hoarding disorder patients had to decide whether to keep or discard their own possessions; it under-activated during decision-making about others’ possessions. The left and right insula (upper left and right) similarly differentially activated in hoarding disorder patients during this task. Picture shows fMRI data superimposed on structural MRI scan LPC Continuing Education Source: David Tolin, Ph.D., Hartford Hospital Reference Neural Mechanisms of Decision Making in Hoarding Disorder Tolin DF, Stevens, MC, Villavicencio AL, Norberg MM, Calhoun VD, Frost RO, Steketee G, Rauch SL, Pearlson GD. Arch Gen Psychiatry. 2012;69(8):832-841. doi:10.1001.

No comments: