A new Canadian study provides insight on how aging interferes with perceptions of time, which can complicate tasks such as driving or other activities that call for perceptual skills.
University of Waterloo investigators describe the challenges faced by older adults as being similar to watching a video with the audio out of synch.
Specifically, investigators found that many seniors have a harder time distinguishing the order of events than younger adults.
Researchers discovered that when both a light and sound were presented at the same or different times, young and older adults could determine with similar accuracy as to whether they occurred simultaneously. But, when asked to determine which appeared first, the light or the sound, older adults performed much worse.
“To make sense of the world around us, the brain has to rapidly decide whether to combine different sources of information,” said Dr. Michael Barnett-Cowan, a professor in the Department of Kinesiology and senior author on the paper.
“Older adults often experience problems processing multisensory information, which in turn can affect everyday tasks from following conversations, to driving, to maintaining balance.”
In another test, researchers showed the study participants two lights travelling towards one another. Usually the lights appear to stream past each other, but when a sound occurs close to when the lights touch, they seem to bounce off each other.
In this test, older adults continued to perceive the lights as bouncing even when the sound occurred well before or after the lights touched, suggesting that older adults combine sensory information that should not belong together.
This is the first study to test multiple ways in which younger and older people combine sensory information in time.
Investigators believe the findings provide new hope that by strengthening the link between these brain processes as people age, the impairments in distinguishing the order of events and perceived collisions could reduce.
For example, possible solutions for improving impaired perceptions of time in the older adults could come from training using video games or brain stimulation.
“Health professionals are able to address many changes in our vision and hearing as we age using corrective lenses and hearing aids, for example. But these interventions don’t help with changes in the brain’s ability to combine sensory information,” said Barnett-Cowan.
“If we can identify and address impaired timing of events in the elderly, we could potentially improve the quality of life, safety, and independence for many older people.”
The findings are especially important for driving skills.
Seniors are the fastest growing segment of the driving population. According to Canada’s National Blueprint for Injury Prevention in Older Drivers, driving-related deaths are the leading cause of accidental deaths individuals aged 65 to 75 years of age.
The number of older drivers is expected to double by 2040. As such, Barnett-Cowan said it is possible that the tests in the current study could one day be part of driver examinations required for older drivers.
The study appears in the journal Experimental Brain Research.