They took out big loans, became compulsive shoppers, and hedged on an infinite real estate market.

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Many compulsive shoppers also suffer from depression, anxiety or eating disorders, and about half of them are also hoarders.

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Compulsive shoppers have reported experiencing a sense of tension or anxiety before buying and feeling a sense of relief after a purchase.

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Most compulsive shoppers have other problems as well, including depression, anxiety or other addictions, including compulsive sexual behavior, Internet addiction or compulsive gambling.

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Compulsive shoppers themselves often have a sense of what drives them.

WSJ: Shop 'Til You Stop: How to Treat Compulsive Spending

In an as yet unpublished study, Dr. Black and colleagues found that 26 compulsive shoppers had similar executive function (the ability to plan, organize, reason and anticipate consequences) as 32 control subjects.

WSJ: Shop 'Til You Stop: How to Treat Compulsive Spending