Cerebral lateralization of vigilance: a function of task difficulty.
Functional near infrared spectroscopy (fNIRS) measures of cerebral oxygenation levels were collected from participants performing difficult and easy versions of a 12 min vigilance task and for controls who merely watched the displays without a work imperative. For the active participants, the fNIRS measurements in both vigilance tasks showed higher levels of cerebral activity than was present in the case of the no-work controls. In the easier task, greater activation was found in the right than in the left cerebral hemisphere, matching previous results indicating right hemisphere dominance for vigilance. However, for the more difficult task, this laterality difference was not found, instead activation was bilateral. Unilateral hemispheric activation in vigilance may be a result of employing relatively easy/simple tasks, not vigilance per se.
Helton
William S
WS
Department of Psychology, University of Canterbury, Private Bag 4800, Christchurch, New Zealand. wshelton@mtu.edu
Warm
Joel S
JS
Tripp
Lloyd D
LD
Matthews
Gerald
G
Parasuraman
Raja
R
Hancock
Peter A
PA
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001143:Arousal / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000378:metabolism / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010108:Oxyhemoglobins / Q000378:metabolism; D011897:Random Allocation; D011930:Reaction Time; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D055815:Young Adult
D010108:Oxyhemoglobins