Electrophysiological correlates of anticipatory and poststimulus components of task switching.
Task-switching paradigms can shed light on cognitive and neural processes underlying attentional control mechanisms. An alternating runs task-switching paradigm (R. D. Rogers & S. Monsell, 1995) is used to identify ERP components associated with anticipatory and poststimulus components of task-switching processes. Subjects alternated between two tasks in a predictable series (AABB). Reaction time (RT) switch cost reduced with increasing response-stimulus (R-S) interval and a residual switch cost remained at the longest R-S interval. A switch-related positivity (D-Pos) developed in the R-S interval. D-Pos was time-locked to response onset, peaked around 400 ms post-response onset, and was unaffected by task-set interference. A switch-related negativity (D-Neg) emerged after stimulus onset. D-Neg peaked earlier with increasing R-S interval and its amplitude and latency were affected by task-set interference. D-Pos and D-Neg were interpreted within current models of task-switching.
Karayanidis
Frini
F
Discipline of Psychology, School of Behavioral Sciences, Newcastle University, Callaghan, New South Wales, Australia. frini.karayanidis@newcastle.edu.au
Coltheart
Max
M
Michie
Patricia T
PT
Murphy
Karen
K
D000293:Adolescent; D000328:Adult; D004569:Electroencephalography; D004576:Electromyography; D004585:Electrooculography; D004594:Electrophysiology; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007858:Learning / Q000502:physiology; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology