TUESDAY, April 26 (HealthDay News) -- Slowing of the brain's processing speed as people age is the prime cause of typical communication problems in older adults, new research indicates.

In the study, University of Kansas researchers compared the ability of young and older adults to do two things at once: keep a cursor on a moving target on a computer screen while responding to questions. Overall, younger adults did better at this dual-tasking.

"We didn't find much evidence that working memory or long-term memory play a role in dual-tasking, but we think that processing speed does," psychology professor Susan Kemper, a senior scientist at the Gerontology Center at the university's Life Span Institute, said in a university news release.

"What I think is going on is that you have to rapidly switch your attention from tracking to talking, going back and forth pretty rapidly, and that's where the processing speed really comes in," Kemper said. "Older adults seem to be slower at switching between tasks so their functional ceiling is lower."

The study findings were published recently in both the Journal of Gerontology: Psychological Sciences and Psychology and Aging.

Language and communication problems, especially those that occur during dual-tasking, may be early indicators of the onset of Alzheimer's disease or other types of dementia, Kemper said.

"We know that there are brain markers even for people in their 40s who may be on the verge of developing dementia," Kemper said. "But those are revealed by very expensive tests that are not widely available. So perhaps language and communication might provide early warning signs that might be picked up and also serve as an access point for trying to develop interventions."

More information

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