Neuroscientist Natalie Denburg said that some individuals may experience disproportionate aging of a brain region critical for decision-making.

"Our research suggests that elders who fall prey to fraudulent advertising are not simply gullible, depressed, lonely or less intelligent. Rather, it is truly more of a medical or neurological problem," Denburg said in a statement. "Our work sheds new light on this problem and perhaps may lead to a way to identify people at risk of being deceived."

The study, published in the Annals of the New York Academy of Sciences, found that 35 percent to 40 percent of a test group of 80 healthy older adults with no apparent neurological deficits have poor decision-making abilities as tested in a laboratory experiment known as the Iowa Gambling Task.

The IGT is a computerized decision-making test in which participants draw cards from different decks with the aim of maximizing their winnings -- some decks yield good results in aggregate, while others yield poor outcomes.