The reaction time of eye-head coordination in man

The reaction time of eye-head coordination was studied in man in connection with different target angles. Both the reaction time of the electromyographic activity in neck and that for the saccadic eye movement increased with increase of visual target angles. The increases of these two reaction times are parallel, with a remaining constant separation around 45 msec. Head movement followed the saccade with an interval of 20–40 msec irrespective of the target angles. The observed increase of reaction time is too large to be explained by intraretinal conduction time. It is postulated to reflect a central mechanism involved in eye-head coordination.