If you've ever watched A&E's Hoarders and wondered what makes it so hard for the show's subjects to throw away their clutter, a new study may have an answer for you. Researchers scanned the brains of 43 people with the hoarding disorder and compared them to those of individuals who did not have the disorder, and others who had obsessive compulsive disorder, which has long been thought to be linked to hoarding, LiveScience reports. During the brain scans, participants were shown pictures of their own junk mail and similar clutter accumulated by the research facility, then asked to make decisions about what to throw away.
Researchers found that the parts of the brain used to decide how essential and relevant things are go into overdrive when hoarders were attempting to make decisions about their own items. The study leaders speculate that hoarders may feel under-stimulated when examining their cluttered home as a whole, but over-stimulated when asked to make specific decisions about what to keep and what to junk, causing them to freeze up and feel anxious or depressed. Surprisingly, those with OCD but not hoarding disorder didn't have the same problem, suggesting the two illnesses are not necessarily aligned. (More hoarders stories.)