Pro- and antisaccade task-switching: response suppression—and not vector inversion—contributes to a task-set inertia

Abstract

Alternating between different tasks represents an executive function essential to activities of 2 daily living. In the oculomotor literature, reaction times (RT) for a 'standard' and stimulus-3 driven (SD) prosaccade (i.e., saccade to target at target onset) are increased when preceded by a 4 'non-standard' antisaccade (i.e., saccade mirror-symmetrical to target at target onset), whereas 5 the converse switch does not elicit a RT cost. The prosaccade switch-cost has been attributed to 6 lingering neural activityor task-set inertiarelated to the antisaccade executive demands of 7 response suppression and vector inversion. It is, however, unclear whether response suppression 8 and/or vector inversion contribute to the prosaccade switch-cost. Experiment 1 of the present 9 work had participants alternate (i.e., AABB paradigm) between minimally delayed (MD) pro-10 and antisaccades. MD saccades require a response after target extinction and necessitate 11 response suppression for both pro-and antisaccadesa paradigm providing a framework to 12 determine whether vector inversion contributes to a task-set inertia. In Experiment 2, 13 participants alternated between SD pro-and MD antisaccadesa paradigm designed to 14 determine if a switch-cost is selectively imparted when a SD and standard response is preceded 15 by a non-standard response. Experiment 1 showed that RTs for MD pro-and antisaccades were 16 refractory to the preceding trial-type; that is, vector inversion did not engender a switch-cost. 17 Experiment 2 indicated that RTs for SD prosaccades were increased when preceded by a MD 18 antisaccade. Accordingly, response suppression engenders a task-set inertia but only for a 19 subsequent stimulus-driven and standard response (i.e., SD prosaccade). Such a result is in line 20 with the view that response suppression is a hallmark feature of executive function.

Acute stress imparts a transient benefit to task-switching that is not modulated following a single bout of exercise

“…Pre-TSST prosaccade task-switch RTs were longer than their task-repeat counterparts, whereas antisaccade task-switch and task-repeat RTs did not differ. In other words, a unidirectional prosaccade switch-cost was present pre-stress and is in line with prior work by our group ( Weiler and Heath, 2012a , 2014a ; Weiler et al, 2015 ; Heath et al, 2016 ; Tari and Heath, 2019 Tari et al, 2019 Heath and Shukla, 2020 ; Shukla et al, 2020 ; Shukla and Heath, 2021 ) and others ( Manoach et al, 2007 ; Chan and DeSouza, 2013 ). When considering this finding, it is important to note that some have argued that the RT difference between prosaccade task-switch and task-repeat trials may reflect a repetition; that is, the second of two consecutively performed prosaccades is associated with an RT reduction.…”

The unidirectional prosaccade switch-cost: no evidence for the passive dissipation of an oculomotor task-set inertia

“…In the other two conditions, the length of the preparation interval was increased to between 3000–4000 ms (i.e., medium preparation interval) and 5000–6000 ms (i.e., long preparation interval), respectively. The short preparation interval entails the same protocol as previous work by our group (Weiler and Heath 2012a , b ; Weiler and Heath 2014a , b ; Weiler et al 2015 ; see also Tari et al 2019 ; Tari and Heath 2019 ; Shukla et al 2020 ; Shukla and Heath 2021 ), whereas the medium preparation interval reflects that used in a previous parity and consonant/vowel switching task (Meiran et al 2000 ). In turn, the long preparation interval was used based on neuroimaging work demonstrating that the neural activity of an antisaccade persists for up to 6000 ms (Duschek et al 2018 ).…”