Cue recruitment in active control of a moving line

Abstract

The visual system can actively recruit new cues for perception (eg Haijiang et al, 2006Proceedingsof the National Academy of Sciences of the USA103483 ^ 488). To explore whether this cuerecruitment occurs in visuomotor control, we examined observers' performance as they used a joy-stick to keep a horizontal line centered while its vertical position was randomly perturbed, eitherunder velocity or acceleration controller dynamics. Observers needed position feedback for velocitycontrol, and velocity feedback for acceleration control. An additional colour cue was introducedby making the line appear redder the more it deviated from the display center (position ^ colourcue) or the faster it moved (motion ^ colour cue). For velocity control, the overall rms positionerror was smaller in the position ^ colour condition than in the no-colour or motion ^ colourconditions (13:7 8:4% and8:9 4:1% smaller, mean SE,Nà4); for acceleration control, therms error was smaller in the motion ^ colour than in the no-colour or position ^ colour conditions(26:8 15:1% and9:8 7:1% smaller). The visuomotor system can selectively recruit novel cuesto enhance existing perceptual information for purposes of control.