It is easy to watch the popular reality TV shows about hoarders and make a judgment. The scenes of clutter and garbage piled so high that the house is barely habitable trigger feelings of both disgust and pity. How can people live that way? This is what many of us ask when we see this and we struggle to comprehend the situation, how someone can let it get so bad, and how they can refuse help. From the outside, it is easy to judge, but difficult to understand what is going on in the mind of a hoarder. Hoarding and OCD Traditionally, hoarding has been seen as a subcategory of obsessive compulsive disorder, or OCD. OCD is a mental health disorder that is characterized by obsessive thoughts, most typically about bad things that could happen to the sufferer or her loved ones. The obsessive thoughts are followed by compulsive actions that she believes will keep the thoughts in check or prevent the bad things from happening. The compulsive behaviors are often part of a rigid routine and are repeated regularly. For instance, someone with OCD might feel compelled to turn a light switch on and off 10 times before going to bed at night. Hoarding, in its own way is also a compulsive and obsessive type of thinking. Hoarders struggle to get rid of personal belongings, even seemingly insignificant items like junk mail or recyclable plastic containers. The items pile up in the house and even when it becomes unlivable, the person refuses to throw anything away. Mounting evidence is indicating that hoarding is not the same thing as OCD and that it is not a subtype of the disorder either. Research is finding distinctions between the two and has led the new, fifth edition of the Diagnostic and Statistical Manual of Mental Disorders to include a separate diagnosis for hoarding disorder. Recent Research A recent study, the results of which were published in the Archives of General Psychiatry, has shed new light on the brains of those who exhibit hoarding behaviors. Led by David Tolin from the Institute of Living, the study scanned the brains of people identified as hoarders and those with OCD, as well as normal controls, using magnetic resonance imaging, or MRI. Over 100 people participated in the study including 43 hoarders, 31 with OCD, and 33 controls. The study participants were told to bring a pile of junk mail from home. While undergoing the brain scans, the people were shown pieces of their own mail as well as pieces belonging to the lab. They were asked to make choices about both types of junk mail as to whether it should be kept or shredded. The participants who had been identified as hoarders chose more often to keep their own junk mail than either the OCD or the control participants. That hoarders would choose to keep more was not surprising, but as they made the choice, the MRI picked up interesting brain activity. The brain activities of the hoarders differed from that of both of the other types of participants when trying to decide about keeping or destroying mail. The hoarders\u2019 scans displayed extra activity in a decision-making region of the brain called the anterior cingulate cortex. They also had more activity in the insula, which is a part of the brain related to negative emotions like shame and disgust. The Hoarding Brain What the research illustrates is that hoarders really struggle to make decisions, especially when those decisions relate to their personal possessions. Hoarders\u2019 brains give too much value to their things, which makes it extremely difficult to throw them away, even when to the rest of us they appear to be junk and valueless. Although not to the same extent, the hoarders exhibited difficulty deciding to throw out the junk mail that did not belong to them. The research also helped to explain how hoarders are able to live in squalid conditions. While certain regions of the brain were overactive when making choices about the junk mail, the hoarder brain overall showed less activity than the brains of the control and OCD participant. This may justify the ability to live with unbelievable amounts of clutter and to not be bothered by it. The lower activity is similar to what is seen in the brains of people with autism who are disconnected from many aspects of the world around them. Hoarders may similarly be able to disconnect from their surroundings. The research is important in many ways, not least of which is that it gives those of us who are not hoarders the ability to understand people who are. They are not lazy, disgusting, or pathetic. Their brains simply work differently and the result is that they struggle greatly to dispose of the things around them.