Abstract
Effective motor control involves both the execution of appropriate responses and the inhibition of inappropriate responses that are evoked by response-associated stimuli. The inhibition of a motor response has traditionally been characterized as either a voluntary act of cognitive control or a low-level perceptual bias arising from processes such as inhibition of return and priming. Involuntary effects of top-down goals on motoric inhibition have been reported, but involve the perseveration of an inhibitory strategy. It is unknown whether the inhibition of a motor response can be selectively triggered by a goal-relevant stimulus, reflecting the automatic activation of a top-down inhibitory strategy. To explore this issue, we used a variant of the flankers task to determine whether irrelevant flankers that share a defining feature (a specific color) with a no-go target can selectively elicit motoric inhibition as revealed through a reverse compatibility effect. Participants were presented with centrally-presented targets that could be either red or blue, with red targets requiring the execution of a response (go targets) and blue targets requiring the withholding of a response (no-go targets). The targets were preceded by known-to-be irrelevant flankers that could be either compatible or incompatible with the upcoming target in their associated motor response, and they could be either the same color as the go target, the same color as the no-go target, or a different, neutral color (green). The results show that no-go color flankers selectively produce a reverse compatibility effect while the other color flankers are ignored, even when participants are given sufficient time to ignore the flankers and focus exclusively on identifying the target. The results thus demonstrate the involuntary inhibition of a motor response contingent on task goals, suggesting that goal-directed motoric inhibition can proceed in stimulus-driven fashion without the need for voluntary cognitive control.
Meeting abstract presented at VSS 2013