A psychophysiological analysis of inhibitory motor control in the stop-signal paradigm.
We examined two potential inhibitory mechanisms for stopping a motor response. Participants performed a standard visual two-choice task in which visual stop signals and no-go signals were presented on a small proportion of the trials. Psychophysiological measures were taken during task performance to examine the time course of response activation and inhibition. The results were consistent with a horse race model previously proposed to account for data obtained using a stop-signal paradigm. The pattern of psychophysiological responses was similar on stop-signal and no-go trials suggesting that the same mechanism may initiate inhibitory control in both situations. We found a distinct frontal brain wave suggesting that inhibitory motor control is instigated from the frontal cortex. The results are best explained in terms of a single, centrally located inhibition mechanism. Results are discussed in terms of current neurophysiological knowledge.
van Boxtel
G J
GJ
Department of Psychology, University of Amsterdam, Roestersstraat 15, 1018 WB, Amsterdam, The Netherlands. g.j.m.vboxtel@kub.nl
van der Molen
M W
MW
Jennings
J R
JR
Brunia
C H
CH
D000328:Adult; D005071:Evoked Potentials; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D008297:Male; D009048:Motor Skills; D013647:Task Performance and Analysis