Antisaccades and task-switching: interactions in controlled processing

Abstract

Smaller latency costs for switching from dominant (habitual) to non-dominant (unusual) tasks compared to the reverse direction have been noted in some studies of task-switching. This asymmetry has been cited as evidence of inhibitory effects from the prior trial. We examined accuracy and latency costs of task-switching between prosaccades and antisaccades, where task-switching is limited to stimulus-response re-mapping and occurs between tasks highly asymmetric in dominance. Eighteen subjects executed prosaccades and antisaccades in single-task and mixed-task blocks. In mixed-task blocks, antisaccade and prosaccade trials were ordered randomly, resulting in 'repeated' trials that were preceded by the same type of trial (i.e. antisaccade-antisaccade), and 'switched' trials that were preceded by the opposite type of trial. Comparisons of the single-task blocks and repeated trials of the mixed-task blocks indexed the mixed-list costs, which were small for prosaccades and insignificant for antisaccades. Comparison of the repeated and switched trials from the mixed-task blocks indexed the residual task-switch cost. Accuracy costs of task-switching and antisaccades were equivalent. The accuracy of trials incorporating both switching and antisaccades in a single response (i.e. switched antisaccade) equalled the product of the accuracies of doing each operation alone, supporting independence of these two functions. In contrast, the latency cost of antisaccade performance was 3 times greater than that of task-switching. Task-switching from prosaccades to antisaccades resulted in a paradoxical decrease in antisaccade latency. This decrease correlated with other indices of vigilance, with the paradoxical effect minimized in more attentive observers. The latency data suggest that either an antisaccade on the prior trial perturbs saccadic responses more than a task-switch, or concurrent task-switching specifically facilitates antisaccades. In either case, the paradoxical benefit of task-switching for antisaccades challenges current models of task-switching.

Effects of anxiety on task switching: Evidence from the mixed antisaccade task

“…The participants exhibited the predicted switch benefit in antisaccade latency when required to switch between anti-and prosaccade trials (mixed-task block), as compared with when they completed anti-and prosaccade tasks separately in blocks of repeated trials (single-task blocks). The paradoxical improvement in antisaccade latency is consistent with the results of previous research (e.g., Barton et al, 2002;Cherkasova et al, 2002;Hodgson et al, 2004;Manoach et al, 2002), in which similar paradoxical reductions in antisaccade latencies were reported when participants were required to switch.…”

Stimulation of the Frontal Eye Field Reveals Persistent Effective Connectivity after Controlled Behavior

“…However, the association was not observed on trials after prosaccade. It has been argued that response slowing on trials after antisaccade is due to a carryover of a general inhibitory control mechanism over a saccade response system rather than due to requirement of inhibiting a previous task set (Cherkasova et al, 2002;Barton et al, 2006). The effective connectivity pattern that we observed in the present study may reflect such a carryover of an inhibitory control mechanism subserved by the neural network involving the FEF.…”

“…In a Stroop paradigm in which subjects switch between automatic word reading and controlled color naming tasks, a greater switch cost is observed on a word-reading trial after color naming than on a color-naming trial after word reading (Allport et al, 1994). Also, when switching between prosaccade and controlled antisaccade, that is, when switching between rules to make a saccade to and away from a visual target, a greater switch cost is observed on a prosaccade trial that follows an antisaccade trial than on an antisaccade trial that follows a prosaccade trial (Cherkasova et al, 2002;Fecteau et al, 2004;Barton et al, 2006). Moreover, responses become faster when switching from prosaccade to antisaccade than when repeating antisaccade.…”

Depressive symptoms and cognitive control in a mixed antisaccade task: Specific effects of depressive rumination

“…This antisaccade switch benefit has been observed in a number of studies (e.g., Hodgson, Golding, Molyva, et al, 2004;Experiment1;Cherkasova, Manoach, Intriligator & Barton, 2002) using a variety of mixed antisaccade paradigms. This antisaccade switch benefit has been argued to reflect a greater allocation of attentional resources in the more attention demanding switch trials (Kristjansson, Chen, & Nakayama, 2001).…”