Changes in motion perception following oculomotor smooth pursuit adaptation.

The hypothesis that oculomotor smooth pursuit (SP) adaptation is accompanied by alterations in velocity perception was tested by assessing coherence thresholds, using random-dot kinematograms before and after the adaptation paradigm. The results showed that the sensitivity to coherent motion at 10 deg/sec (the initial target velocity during adaptation) was reduced after the SP adaptation, ending up at a level that was between those normally observed for velocities of 10 and 20 deg/sec. This is consistent with an overestimation of the velocity of the coherent motion and suggests that SP adaptation alters not only the oculomotor output, but also the perception of target velocity.