Perception of timing of kinesthetic stimuli

A psychophysical method was used to estimate the timing of perception of ki nesthetic stimuli with different velocities in normal volunteers. A 1 ms au ditory click occurred randomly before or after an imposed flexion movement at either 20, 40 or 60 deg/s of the metacarpophalangeal joint. Subjects rep orted whether the click was perceived before or after the movement onset (e xperiment 1) or perception of movement velocity (experiment 2). The time at which there was a 50% chance that subjects reported movement or velocity p erception after the click was taken as an estimate of the time subjects per ceived the stimuli. The difference in time of perceived movement velocity d iscrimination and movement onset was only significant when the velocity was 20 deg/s (52 ms). This suggests that movement onset and identification of the velocity of the faster movements are perceived nearly simultaneously. ( C) 1998 Lippincott Williams & Wilkins.