Is your mind like a sieve? Blame multitasking, say NUS scientists

If you are inclined to blame your fading memories - from holidays years ago to even big occasions such as your wedding - on having too much to do at the same time, you may be on to something.

A study by scientists from the National University of Singapore (NUS) has found that multitasking may impair the forming of long-term memories, which in turn could increase the risk for Alzheimer's disease or early onset dementia.

The capacity to form memories is compromised if too many of them compete for "memory proteins" in the brain.

"It is like six people trying to eat a cake made for two. They will still be hungry," said principal investigator S. Sajikumar, from the department of physiology at the NUS Yong Loo Lin School of Medicine.

The pervasiveness of social media, as well as stressful work lives, can play a part in this, he added.

Memories are believed to be stored in synapses, the contact points of roughly 100 billion neurons, cells in a person's brain that transmit information.

Long-term memories are stored after they "win" proteins over other memories in the brain. But multitasking within any given one-hour period intensifies this competition to a point where "nobody wins", said Dr Sajikumar. He discovered this by artificially stimulating synapses in the brain tissues of mice.

For instance, he said, a person may remember the name of the wine he or she drank on their wedding day. However, if the person had to juggle many activities simultaneously, the wine's name may be forgotten with time.

"This is especially not good for youngsters 12 and below, because their neural networks are still developing. Multitasking will impair this development. They could be at greater risk of attention deficit syndrome," said Dr Sajikumar.

Parents can help by limiting how much their children are made to multitask, by having them experience activities like reading one at a time, he said.

The three-year study was done in collaboration with the Technical University Braunschweig and the University of Edinburgh. It has received $850,000 of funding from the National Medical Research Council.

The findings were published last week in the notable journal, Proceedings of the National Academy of Sciences of the United States of America.

Said Dr Sajikumar: "There is a saying in India: 'While you eat, you eat. While you hear, you hear'... Don't do things simultaneously. Have a break, and then do it. This break will (help you) recall more information... Chronic multitasking is not at all good for our neural system."

davidee@sph.com.sg

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