Neurophysiological and behavioral indices of time pressure effects on visuomotor task performance

Using a video game format, this study examined the effects of time pressure (TP) on behavioral and electrocortical indices. The behavioral results wer e consistent with previous time pressure research in that TP reduced time t o perform a task and increases behavioral errors. In addition, electroencep halogram (EEG) measures showed distinctive patterns associated with TP in t he theta, mu, and gamma bands along the midline, Site specific changes in t he success vs. failure trials were also seen in midline theta at Fz, gamma at Fz, and mu at Cz. Right parietal alpha also differentiated TP and succes s vs. failure trials. In specific TP (1) increased frontal midline theta ac tivity and (2) increased gamma at. midline (frontal, central, and partietal ) and in right frontal areas. The results of these findings are discussed i n terms of the formation of specific neurocognitive strategies as evidenced by the topographic distribution of task-related modulation of the EEG with in certain frequency bands. It is suggested that the effect of TP on visuom otor performance is mediated by adopting either task-relevant or task-irrel evant neurocognitive strategies as evidenced by successful or failed trials , respectively. Whether these strategies are formulated prior to performanc e or appear spontaneously during task performance remains unclear and is aw aiting further experimentation. (C) 2000 Elsevier Science B.V. All rights r eserved.