Multi-tasking may actually improve performance: study

People can do two things at once and do them both well, according to a new study that challenges the notion that multi-tasking causes one or both activities to suffer.
In a study of older adults who completed cognitive tasks while cycling on a stationary bike, University of Florida researchers found that participants' cycling speed improved while multi-tasking with no cost to their cognitive performance.
Researchers originally set out to determine the degree to which dual task performance suffers in patients with Parkinson's disease.
They had a group of patients with Parkinson's and a group of healthy older adults complete a series of increasingly difficult cognitive tests while cycling.

Participants' cycling speed was about 25 per cent faster while doing the easiest cognitive tasks but became slower as the cognitive tasks became more difficult.
Yet, the hardest tasks only brought participants back to the speeds at which they were cycling before beginning the cognitive tasks.

The findings suggest that combining the easier cognitive tasks with physical activity may be a way to get people to exercise more vigorously.
During the study, 28 participants with Parkinson's disease and 20 healthy older adults completed 12 cognitive tasks while sitting in a quiet room and again while cycling.
Tasks ranged in difficulty from saying the word 'go' when a blue star was shown on a projection screen to repeating increasingly long lists of numbers in reverse order of presentation.

Their cycling speed was faster while performing the cognitive tasks, with the most improvement during the six easiest cognitive tasks. Cognitive performance while cycling was similar to baseline across all tasks, researchers said.
The reasons for participants' multi-tasking success most likely include multiple factors, the researchers said, but they hypothesise that one explanation could be the cognitive arousal that happens when people anticipate completing a difficult cognitive task.
Similarly, exercise increases arousal in regions of the brain that control movement. Arousal increases the release of neurotransmitters that improve speed and efficiency of the brain, particularly the frontal lobes, thus improving performance in motor and cognitive tasks.

The study was published in the journal PLOS ONE.