With the new mobile phone law coming into effect in Ontario (many jurisdictions in North America already have similar laws in force) distractions while fiddling with the phones should be severely reduced but a new study shows that most of the distraction is still present while using hands-free devices. The problem has to do with working memory or rather the way it works talking to someone in the car versus someone who is not. There have been a number of studies to show you can be just as distracted while holding a mobile phone as you are using a hands-free device but a new study speculates on why this is so. Working memory may be quite taxed in a conversation and some of it needs to be freed up to cope with an emergency situation such as a road hazard. Working memory is one aspect of the human brain that has a limit on how well it will work and an earlier post on this blog suggests this is somewhere between seven and nine items–such as numbers, words or visual relationships for everyone. The study used a driving simulator while the test subjects held conversations with passengers who were in the car and with others who were not. Those who had conversations with others who were not in the car demonstrated slow reaction times in speed of braking responses and hazard avoidance. What the researchers found was that when the other party was in the car they demonstrated “conversation suppression”. In other words their speech slowed down in reaction to hazards they could see being in the car with the driver and this allowed the driver to free up working memory and shift focus to the road. Of course other parties in conversations with the driver who were not in the car demonstrated no such conversation suppression because they could not see the hazards. As an end-note the researchers say that talking to an in-car passenger might actually improve driver performance because both parties are able to see any hazard on the road that might present itself and the passenger can provide a verbal warning to the driver and even point to the hazard focusing the driver even more.
I spend a lot more time than I care to admit surfing the web and most of the time these sessions start with logging on to Google. Now, a new study reported in The Times of India indicates that this simple activity may be keeping my brain young. The study, conducted by Gary Small, a professor of neuroscience and human behavior at the University of California at Los Angeles shows that this simple activity can slow the effects of dementia. He claims that Googling consistently stimulates the brain to slow or even reverse the declines that can end with dementia.
Teena Moody, coauthor of a report on the study said, “Searching online may be a simple form of brain exercise that might be employed to enhance cognition in older adults.”
Small’s study observed 24 men and women between ages 55 and 78 and half of these were regular users of the net. Using a medical procedure called fuctional magnetic resonance imaging after half hour session at the computer, the study noted activity in the regions of brain associated with language, reading, memory and vision.
A second scan after the computer sessions showed that brain activity had widened to include areas associated with working memory and decision making. The conclusion of the study was that Internet searching stimulates brain cells and neural pathways.
Teena Moody, a coauthor of the study report said, “Searching online may be a simple brain exercise that could be employed by older adults to enhance cognition.”
Some time ago I wrote about an interview I conducted with a researcher at Baycrest Geriatric Hospital here in Toronto in which the researcher talked about practical applications of some of the research they were doing in dementia and its precursor, Mild Cognitive Impairment. Her conclusion was that learning a second language could delay the onset of dementia by five years. At the time I remember thinking how wonderful this was that you could do something about dementia but at the same time I was overcome with the effort involved in learning another language. After reading The Times of India report, I am relieved that there is something I can do that is simpler and easier. To top it off it is something I already do more times a day than I care to admit.
A recent study by British and German scientists found that the part of the brain usually associted wtih long-term memory may also be associated with working memory. The study focused on the hippocampus which has traditionally been thought to have a role in long-term memory, spatial memory and navigation. This is also one of the first parts of the brain to suffer in patients with Alzheimer’s disease.
The study looked at patients with temporal lobe epilepsy which causes problems in the hippocampus leading to short-term memory problems. The researchers said, “The patients could not distinguish the studied images from new images after 60 minutes but performed normally after five seconds.” Professor Emrah Duzel of University College London went on to say that a striking deficit emerged even at five seconds when the subjects were asked to recall the detailed arrangements of objects within scenes in photographs.
The study concluded that there are two distinct short-term memory networks within the brain. The other one that is separate from the hippocampus remains intact in patients with hippocampus-related disorders.
Nathan Cashdollar, also from University College London said, “This is the fist functional and anatomical evidence showing which mechanisms are shared between short-term and long-term memory and which are independent.”
The findings of this study, I think, are interesting in showing that there are distinct elements to short-term memory and that they are located in different areas of the brain. When I was in Dr. Attila Turgay’s (one of the leading experts on ADHD in Canada) office last year he did three separate tests for short-term memory: verbal, numerical and spatial. It was only spatial short-term memory with which I had trouble. If indeed this function is located in a different part of the brain than either verbal or numeric working memory it does make sense that one aspect of working memory would by dysfunctional while the other two are intact.