Citation

Marinovic W, Reid CS, Plooy AM, Riek S, Tresilian JR. J. Neurophysiol. 2011; 105(3): 1122-1129.

Affiliation

1The University of Queensland.

Copyright

(Copyright © 2011, American Physiological Society)

DOI

10.1152/jn.00705.2010

PMID

21123661

Abstract

In order to intercept rapidly moving objects people must predict the right time to initiate their actions. The timing of movement initiation in interceptions is thought to be determined when a perceptual variable specifying time-to-contact reaches a criterion value. If a response needs to be aborted, the performer must make a decision prior to this moment. It has been recently shown that the minimal time to suppress an anticipatory action takes longer during motion extrapolation than during continuous visual information. In Experiment 1, we sought to determine whether or not the availability of visual information would: a) affect the latency to inhibit an anticipatory action, and b) modulate the level of excitability in the motor cortex (M1). The behavioral results showed that the absence of visual information prolonged the latency to stop the movement as previously reported. The neurophysiological data indicated that corticospinal excitability levels were affected by the availability of visual information. In Experiment 2, we sought to verify whether corticospinal excitability levels would also differ between the two visual conditions when the task did not involve response suppression. The results of Experiment 2 indicated that excitability levels did not differ between visual conditions. Overall, our findings indicated that the build-up of motor activation can also play a role in determining different latencies to inhibit an anticipatory action. They also suggest that the build-up of motor activation in the corticospinal pathways can be strategically modulated to the requirements of the task during continuous visual information.

Language: en