Vertex slow potentials and classical reaction time task: Specificity and "directional" anticipatory factors

Abstract

Vertex slow potentials during the foreperiod of a classical reaction time task are shown to be influenced by modality of warning stimulus (auditory vs visual) and Ss variables. A directional anticipatory specificity-defined as a differential expectancy at a given activation level-did not influence morphology of neural events recorded during the foreperiod, neither when developed by means of verbal command nor by conditioned association between warning and imperative stimuli. Results are discussed in terms of the search for physiological correlates of "direction" of the preparatory set. © 1976.