title: Alternating between pro- and antisaccades: switch-costs manifest via decoupling the spatial relations between stimulus and response.
abstract: Antisaccades are a nonstandard task requiring a response mirror-symmetrical to the location of a target. The completion of an antisaccade has been shown to delay the reaction time (RT) of a subsequent prosaccade, whereas the converse switch elicits a null RT cost (i.e., the unidirectional prosaccade switch-cost). The present study sought to determine whether the prosaccade switch-cost arises from low-level interference specific to the sensory features of a target (i.e., modality-dependent) or manifests via the high-level demands of dissociating the spatial relations between stimulus and response (i.e., modality-independent). Participants alternated between pro- and antisaccades wherein the target associated with the response alternated between visual and auditory modalities. Thus, the present design involved task-switch (i.e., switching from a pro- to antisaccade and vice versa) and modality-switch (i.e., switching from a visual to auditory target and vice versa) trials as well as their task- and modality-repetition counterparts. RTs were longer for modality-switch than modality-repetition trials. Notably, however, modality-switch trials did not nullify or lessen the unidirectional prosaccade switch-cost; that is, the magnitude of the RT cost for task-switch prosaccades was equivalent across modality-switch and modality-repetition trials. Thus, competitive interference within a sensory modality does not contribute to the unidirectional prosaccade switch-cost. Instead, the modality-independent findings evince that dissociating the spatial relations between stimulus and response instantiates a high-level and inertially persistent nonstandard task-set that impedes the planning of a subsequent prosaccade.
authors.affiliation: School of Kinesiology, The University of Western Ontario, London, ON, N6A 3K7, Canada. mheath2@uwo.ca.|Graduate Program in Neuroscience, The University of Western Ontario, London, ON, N6A 3K7, Canada. mheath2@uwo.ca.
authors.forename: Matthew
authors.initials: M
authors.lastname: Heath
authors.affiliation: School of Kinesiology, The University of Western Ontario, London, ON, N6A 3K7, Canada.
authors.forename: Caitlin
authors.initials: C
authors.lastname: Gillen
authors.affiliation: School of Kinesiology, The University of Western Ontario, London, ON, N6A 3K7, Canada.
authors.forename: Ashna
authors.initials: A
authors.lastname: Samani
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods*; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods*; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D012438:Saccades / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*; D055815:Young Adult
keywords: Antisaccade; Modality-switching; Prosaccade; Task-set inertia; Task-switching