Dual-task repetition alters event-related brain potentials and task performance.
OBJECTIVE
We examined the modulation of event-related brain potentials (ERPs) and the accuracy of sensori-motor coordination on short-term repetition of the concurrent performance of a somatosensory discrimination (oddball) task and a visuo-motor tracking task.


METHODS
The subjects concurrently performed visuomotor tracking and somatosensory oddball tasks. In the dual-task condition, the subjects performed the visuomotor tracking and somatosensory oddball tasks concurrently for about an hour. In the oddball-only condition, they performed just the oddball task for the same period.


RESULTS
Tracking performance improved with task repetition. The amplitude of the P300 elicited by somatosensory stimulation in the oddball-only condition decreased significantly with task repetition, whereas in the dual-task condition, it showed a complex pattern of change. The earlier responses were decreased in amplitude in the dual-task condition compared to the oddball-only condition, and gradually decreased with task repetition in both conditions.


CONCLUSIONS
Dynamic changes in ERPs and task performance with dual-task repetition support the idea that dual-task repetition produces changes in resource allocation following the automation of stimulus processing in addition to so-called habituation.


CONCLUSIONS
This study also provides evidence for use of ERP amplitudes as physiological indices of functionally different types of resources.
Department of Neurobiology and Behavior, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan. tkida@nagasaki-u.ac.jp
Tetsuo
T
Kida
Takeshi
T
Kaneda
Yoshiaki
Y
Nishihira
D000328:Adult; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010812:Physical Stimulation; D011214:Practice, Psychological; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology