PSYCHOPHYSIOLOGICAL ASPECTS OF SELECTIVE AND DIVIDED ATTENTION DURINGCONTINUOUS MANUAL TRACKING

Central, autonomic, and metabolic physiological measures were observed concurrently along with performance and subjective measures to compar e the effects of tracking task difficulty during selective and divided attention. Eighteen dextral males performed visual compensatory manua l tracking as a primary task while attending to or ignoring secondary- task auditory oddball stimuli. The difficulty of the tracking task was varied factorially by requiring participants to track with accelerati on (second-order) or velocity (first-order) control and high or low ba ndwidth sum-of-sines disturbance, Tracking performance was affected by the difficulty manipulations but not by the attention manipulation. E vent-related brain potential P300 amplitude to oddball target stimuli was sensitive to the division of attention and tracking order-of-contr ol but not to tracking disturbance bandwidth when the oddball task was attended. Oxygen consumption, a measure of aerobic metabolism, was gr eater during acceleration than velocity tracking; however, cardiac mea sures were sensitive only to the division of attention. The results de monstrate that the attention and the task difficulty manipulations hav e physiologically dissociable effects that were interpreted as support ing a cognitive/energetic model of attention. (C) 1997 Elsevier Scienc e B.V.