Article

The simultaneous performance of multiple tasks is often required in daily life.
The dual-task paradigm has been used extensively to evaluate the ability to
perform simultaneous behavioral tasks. However, relatively few studies have been
carried out to determine the muscle and brain activity underlying dual-task
performance. This study determined the influence of single-task and dual-task
conditions on muscle and brain activity by measuring ankle dorsiflexion, surface
electromyography, and magnetoencephalography. Increased muscle activation and
variability in the dorsiflexion interval was observed during dual-task
performance compared with single-task performance, whereas brain activity in the
contralateral motor and frontal areas was reduced. Incidental movement of the
non-task-related ankle (contralateral ankle) showed a different pattern of brain
activity during the dual-task performance in another experiment. These findings
suggest that the activity decreased in several information-processing areas under
dual-task conditions as a result of decentralization of attention. Activity in
the right and left motor fields may play a role in the dual-task performance, as
indicated by changes in brain activity during dual-task performance in two groups
classified according to the activity level of the contralateral ankle.

Langue : ANGLAIS