Why aren’t hoarders bothered by piles of old newspapers and the other junk that clogs their homes?

Scientists may have uncovered an important clue that could help explain why hoarders can live surrounded by mounds of clutter: A brain network that helps us decide whether something should be kept or thrown away may be malfunctioning.

The network appears to go into overload any time a hoarder tries to decide if an object is important, researchers reported in a study published in the Journal of the American Medical Association. At other times, the affected region of the brain goes too quiet, which may explain why they aren’t bothered by those old newspapers piles.

“When you go into a house like that you’ve got to start thinking, ‘How can this person live this way?’” said the study’s lead author, psychologist David Tolin, director of the Anxiety Disorders Center at The Institute of Living in Hartford, Conn. “It can be maddening if you don’t have this problem. But [hoarders] don’t really seem to recognize or appreciate it. The part of the brain that should be saying this is important is underactive.”

Tolin, an adjunct associate professor of psychiatry at the Yale University School of Medicine, and his colleagues compared brain scans from 43 hoarders to those from 31 patients with obsessive-compulsive disorder and 33 healthy volunteers. Before any of the volunteers came in, they were asked to sweep all the papers from a countertop at home into a plastic garbage bag.

“[Participants] were told we wouldn’t throw anything away that they wanted to keep,” Tolin said. Tolin and his colleagues also brought in junk mail from their homes to use as a control. The papers were put into boxes labeled either “My Stuff” or “Your Stuff.”

While in a brain scanner, study volunteers then watched a video screen as a researcher plucked a piece of paper from one of the two boxes and asked if it should be tossed into a shredder.

When hoarders were looking at someone else’s junk, there was very little activity in the brain network that includes the insula and the anterior cingulated cortex. But when they were asked about their own junk, the network sparked wildly.

“These two regions are commonly thought to constitute a network involved with the understanding of the relative importance or significance of something,” Tolin said. “When hoarding participants were not making a decision that was personally relevant it was underactive. That may explain how a person can live in a horrible environment and not seem to care about it. The flip side is that when there’s a personally relevant decision in front of them, such as whether to discard something they own, the region gets hyperactive and they are overwhelmed.”

Tolin suspects that the network hyperactivity sparks an unpleasant sensation, so hoarders just skip making any decisions to avoid the feeling.

It’s not clear whether people are born with this kind of faulty wiring or whether they simply have a predisposition that gets kicked off with the right environmental factors.

Still, Tolin said, the new research may help clinicians come up with better therapies and also explain why certain treatments, like cognitive behavioral therapy seem to work.

The idea behind those treatments is to try to get the brain to rewire through positive experiences. So, Tolin said, a therapist might coach a hoarder going through a pile of papers in the living room by asking the kinds of questions that come naturally to others: Is this something I’ve used in the last six months? If I didn’t have this would I be worse off? Is this of good enough quality that it’s worth keeping?

“Part of what we’re doing is teaching and drilling them on appropriate decision making,” Tolin said. “They’re used to responding to the overwhelming impact of these brain regions. When they start practicing doing it this way, they are actually teaching their brains not to have that reaction.”

Gail Blanke, author of "Throw Out 50 Things: Clear the Clutter, Find Your Life," tells viewers how to get rid of excess junk and TODAY contributor Jill Martin shows how to keep what's left organized.

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