The intrinsic value of visual information affects saccade velocities

Xu, Zee, and Shadmehr (2009) Experimental Brain Research.  

Abstract  Let us assume that the purpose of any movement is to position our body in a more advantageous or rewarding state.  For example, we might make a saccade to foveate an image because our brain assigns an intrinsic value to the information that it expects to acquire at the endpoint of that saccade.  Different images might have different intrinsic values.  Optimal control theory predicts that the intrinsic value that the brain assigns to targets of saccades should be reflected in the trajectory of the saccade.  That is, in anticipation of foveating a highly valued image, our brain should produce a saccade with a higher velocity and shorter duration.  Here, we considered four types of images: faces, objects, inverted faces, and meaningless visual noise.  Indeed, we found that reflexive saccades that were made to a laser light in anticipation of viewing an image of a face had the highest velocities and shortest durations.  The intrinsic value of visual information appears to have a small but significant influence on the motor commands that guide saccades.