Theresa Boyle Staff Reporter
When it comes to talking on your cellphone, beware of multi-tasking.
That's the advice from Toronto academics the day after a woman was killed in Toronto when she walked into a truck while talking on her cellphone.
"There are limits to how much we can attend to at one time," explained Michael Inzlicht, an assistant psychology professor at the University of Toronto, Scarborough campus.
Focusing attention is very much like shining a spotlight, he said yesterday. "You've got a visual array in front of you, but the spotlight will focus only on what's being illuminated," he said, adding you may physically perceive other objects but they won't necessarily register.
The same issue is raised in the debate over the province's plan to ban the use of cellphones while driving.
Inzlicht said it has been long known our brains are not well adapted to handling two demanding tasks at a time and there are numerous studies that show this.
In a 1953 test conducted by Colin Cherry from Imperial College London, participants were asked to wear headphones on which one recording played through the right ear while a different one simultaneously played through the left. Participants could easily tune into either one of the messages, but had difficulty focusing on both at once.
In a 1999 study by Daniel Simons of the University of Illinois and Christopher Chabris of Harvard University, subjects were asked to watch a short video in which two groups of people pass a basketball among themselves. Subjects were told to count the number of passes made by one of the teams or to keep count of bounce passes vs. aerial passes. The viewers were then asked if they noticed anything unusual on the video. In most groups that did the test, 50 per cent of subjects did not notice someone dressed in a gorilla suit walk through the scene. The video has become a YouTube sensation.
Oren Amitay, a psychology lecturer at both Ryerson University and the University of Toronto Scarborough, said our emotional engagement in an activity can also impact our ability to multi-task. He notes that a part of the brain, known as the amygdala, lights up on MRI scans when an individual becomes emotionally engaged.
"When you're really emotionally engaged, that limits your ability to concentrate or to physically do other things," he said. "If you're having a conversation and say all of a sudden you remember some past fight, that amygdala is firing on all cylinders."
Amitay points out when people are walking and talking on their cellphones, they tend to look down.
"... We're trying to block out all these other sensory inputs," he says.
Neither Inzlicht nor Amitay were aware of the particular circumstances that led to the death of the woman in Toronto and were speaking only in generalities.