Individual Differences in Pupil Size and Performance

Accelerated age-related decline in processing resources in schizophrenia: Evidence from pupillary responses recorded during the span of apprehension task

“…In numerous studies (for a review, see Beatty, 1982), increased task processing load (e.g., perceptual discriminability, sentence syntax complexity, number of arithmetic multiplicands) reliably evoked greater pupillary dilation responses, regardless of the cognitive domain tapped by different tasks (e.g., visual detection, language, memory, reasoning). For example, pupillary responses recorded during digit span recall tasks systematically increased in normal individuals after each additional to-berecalled digit was presented and then returned to resting baseline size after the digits were recalled (Granholm et al, 1996b;Peavler, 1974). Larger pupillary responses reflected greater allocation of available resources in these studies, and pupillary responses no longer increased when resource pools were depleted (e.g., when digit spans exceeded available working memory resources; Granholm et al, 1996b;Peavler, 1974).…”

Development of attentional allocation in the dual task paradigm

“…Accuracy on the DS task was measured using a scheme adapted in part from Peavler (1974), whereby two points were awarded for each correct digit recalled in the correct location in the sequence, 1 point was awarded for each correct digit recalled that was not in the correct location and one point was subtracted for digits that were repeated or were not in the original sequence. The accuracy score was based on percent accuracy for each sequence length in each condition.…”

“…The pupillary dilation measure is particularly sensitive to memory load on the digit span (DS), increasing as each digit is presented and reaching a peak just before participants repeat back the digits. Furthermore, pupillary dilation begins to level off or decrease when the number of digits to be remembered exceeds memory span (Granholm et al, 1996;Kahneman and Beatty, 1966;Kahneman et al, 1968;Peavler, 1974).…”

Operator Functional State Assessment (L'evaluation de l'aptitude operationnelle de l'operateur humain)

“…Pupil diameter, while also affected by changes in illumination, stimulus characteristics, and accommodative behaviors, has been shown to generally increase with higher cognitive processing levels (Backs & Walrath, 1992;Beatty & Wagner, 1978;Peavler, 1974). The diameter of the pupil is sensitive to changes in cognitive workload.…”