Lots of studies have shown it isn't safe to talk on a cellphone while driving a vehicle. But fresh evidence indicates that cellphone chatting can also impair pedestrians' judgment - especially if they happen to be seniors.
Research published this week in the journal Psychology and Aging suggests that older adults may be putting themselves at risk if they try crossing a relatively busy street while talking on a cellphone. Simply put, the distraction caused by the conversation "makes it more difficult to navigate those crossings," said one of the study's co-authors, Mark Neider of the University of Illinois.
The study involved 18 older adults (aged 59 to 81) and 18 university students (aged 18 to 26). The volunteers were monitored as they crossed a simulated road in a virtual-reality lab. (They walked on a treadmill as 3-D images were projected around them.)
They faced two different traffic conditions. In one case, the oncoming cars were spaced 75 metres apart; in the second case they were separated by 90 metres. (Ninety metres is almost the length of an American football field.) In both situations, the cars were travelling about 48 kilometres per hour.
The older adults, who were in good mental and physical health, handled the lighter traffic without much difficulty. But they ran into problems once the pace of traffic picked up. They took significantly longer to cross the intersection when they were engaged in a cellphone conversation, compared to not using the device. In particular, they seemed to have a hard time deciding when to step into the street. And their hesitancy often meant they failed to complete the task in the allotted time of 30 seconds, said Dr. Neider.
The younger participants showed no impairment in their ability to multi-task - or walk and talk at the same time.
But that doesn't mean younger pedestrians are immune to the distractions caused by cellphones, said Dr. Neider. In an earlier study, young cellphone users also had difficulty crossing a simulated street in which the traffic was far more challenging than in the experiment involving the seniors.
In some respects, this latest research simply shows that older folks have a limited ability to multi-task, said Art Kramer, also of the University of Illinois, the senior author of the study.
"We know there are a multitude of changes in the brain as part of the normal aging process," said Dr. Kramer. "They occur throughout the brain, but particularly in areas that deal with integrating information and decision making." And those changes can limit a person's ability to do multiple things simultaneously, he said.
So, if you're a senior, it may be a good idea to put away the cellphone when you're heading out for a walk.