By studying patients who developed abnormal hoarding behavior following brain injury, neurology researchers in the University of Iowa Roy J. and Lucille A Carver College of Medicine have identified an area in the prefrontal cortex that appears to control collecting behavior. The findings suggest that damage to the right mesial prefrontal cortex causes abnormal hoarding behavior by releasing the primitive hoarding urge from its normal restraints. The study was published online in the Nov. 17 Advance Access issue of the journal Brain.
Comparison of functional magnetic resonance imaging (fMRI) brain scans between collectors and normal people turned up the location where the collecting behavior comes from.
The UI team studied 86 people with focal brain lesions - very specific areas of brain damage – to see if damage to particular brain regions could account for abnormal collecting behavior. Other than the lesions, the patients' brains functioned normally and these patients performed normally on tests of intelligence, reasoning and memory.
A questionnaire completed by a close family member was used to identify problematic collecting and the behavior was classified as abnormal if the collection was extensive; the collected items were not "useful" or aesthetic; the collecting behavior began only after the brain injury occurred; and the patient was resistant to discarding the collected items.
The questionnaire very clearly split the patients into two groups – 13 patients who had abnormal collecting behavior and a majority (73 patients) who did not. Unlike normal collecting behavior such as stamp collecting, the abnormal collecting behavior of these patients significantly interfered with their normal daily life. Patients with abnormal collecting behavior filled their homes with vast quantities of useless items including junk mail and broken appliances. Despite showing no further interest in the collected items, patients resist attempts to discard the collection.
To determine if certain areas of damage were common to patients who had abnormal collecting behavior, the UI researchers used high-resolution, three-dimensional magnetic resonance imaging to map the lesions in each patient's brain and overlapped all the lesions onto a common reference brain.
"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 behavior," Anderson said. "Our study shows that when this particular part of the prefrontal cortex is injured, the very primitive collecting urge loses its guidance.
So then are stamp collectors and baseball card collectors slightly brain damaged? My guess is that there is a continuum of urges to collect with some people having stronger natural urges that have to find some outlet.
It seems likely to me that just as there are people who have excessive urges to collect there are other people who lack mimimally sufficient urges to collect possessions to be able to keep enough possessions around them to take care of themselves. On average do wealthier people have stronger urges to collect possessions? Do people who buy things have stronger urges to collect objects than people who go and spend their money travelling and entertaining themselves? Seems plausible.
|Share |||Randall Parker, 2004 December 16 02:27 AM Brain Disorders|