This article from the BBC is worth reading.
For more info on OCD click here.
People who hoard apparently useless items may be able to blame an area of their brain, say US researchers.
The University of Iowa team pinpointed a region in the frontal lobe that appeared to control this behaviour.
Researchers have linked hoarding to obsessive compulsive disorder (OCD), but it is not known what causes it and whether it is a unique condition.
The study in the journal Brain adds to growing evidence that hoarding has its own specific underlying mechanism.
OCD is an anxiety disorder in which the person is compelled by irrational fears and thoughts to repeat seemingly needless actions over and over again.
It can manifest itself in repetitive behaviours, such as excessive hand washing, cleaning or repeated checking.
But some people with OCD have a compulsion to hoard things, which is well above and beyond the avid interest of an average stamp collector.
Researchers from the University of California Los Angeles have already shown that people with OCD who also hoard show different brain activity patterns to other OCD patients.
To gain a better understanding of the cause of obsessive collecting behaviour, Dr Steven Anderson and his team studied 13 people who had developed a hoarding compulsion after sustaining a brain injury.
Hoarding was defined as abnormal if it was extensive, the squirreled items were not useful or aesthetic and the individual was unwilling to discard any of their collection.
Some of the patients had filled their homes with vast quantities of junk mail or broken appliances, for example.
They scanned the patients and compared their brain scans with those taken from other 73 brain injured patients who displayed no abnormal collecting behaviour.
The scans showed up an obvious difference.
Dr Anderson said: “A pretty clear finding jumped out at us.
“Damage to a part of the frontal lobes of the cortex, particularly on the right side, was shared by the individuals with abnormal behaviour.
“Patients with OCD and some other disorders, such as schizophrenia, Tourette’s syndrome and certain dementias, can have similar pathological collecting behaviour but we don’t have a pointer to located where in the brain the problem is occurring.
“Our hope is that our findings with these brain lesion studies will lead to insights in these conditions as well.”
Dr Naomi Fineberg, an expert in OCD at Queen Elizabeth Hospital, Welwyn Garden City, said: “These studies, which are really in their infancy, are starting to confirm that hoarding may be different from the rest of OCD.
“The hoarding type is unresponsive to normal OCD treatments, so if we can identify areas of the brain specific for hoarding this will have quite profound implications.
“The more we can start to understand about the neurobiology of hoarding the more we can start to think about targeting treatments accordingly.”
But Professor Paul Salkovskis from the Institute of Psychiatry at King’s College, London, said: “Knowing which area of the brain is affected does not help you in treatment one little bit.
“Potentially, it’s misleading because people feel if you can image a problem it means it is a biologically-based problem.
“At this point there is no evidence that there is any biological difference between these patients.
“The answer is cognitive behavioural therapy.”