A new study finds that brain atrophy in late adulthood can lead to unintended racial prejudice, social inappropriateness, depression and gambling problems.

As humans age, the brain begins to shrink in weight and volume, causing significant atrophy in the front lobes, which can inhibit thought and behavior, according to a study from Australia's University of Queensland.

Psychologist Bill von Hippel reports in a study appearing in the October issue of Current Directions in Psychological Science that this condition in late adulthood may lead to unintended prejudice, social inappropriateness, depression and gambling problems.

In their study, von Hippel and colleagues found that older white adults showed greater stereotyping toward African Americans than younger white adults did, despite being more motivated to control their prejudices.

Von Hippel suggested that “because prejudice toward African Americans conflicts with prevailing egalitarian beliefs, older adults attempt to inhibit their racist feelings, but fail.”

Von Hippel also found that older adults were more likely than younger adults to inquire about private issues including weight gain and family problems in public settings. Although the older adults seemed to know the social rules, they failed to follow them, which is consistent with diminished frontal lobe functioning.

Von Hippel also found that a penchant for gambling can be toxic for older adults, as those with poor executive functioning are particularly likely to have gambling problems. These problems are exacerbated in the afternoon, when older adults are less mentally alert.

Older adults were more likely to get into an unnecessary argument and were also more likely to gamble all their money away later rather than earlier in the day, the study found. Researchers suggested scheduling the social activities or gambling excursions of the elderly earlier in the day when they are more mentally alert.

The inability to control their behaviors also led to depression in many elderly adults, von Hippel said.