Proprioception as a mediator in the timing of motor responses.

The hypothesis that proprioceptive feedback from early portions of a total movement may serve as a cue for the anticipation and timing of a later portion was tested using 48 5s. The right-hand task involved anticipation (with no preview) of the coincidence of a moving and a stationary pointer, and proprioceptive feedback was manipulated by having 5s make a minimal movement or a small or large rotary movement with the left hand during the interval to be timed. Although neither absolute nor algebraic error was affected by the treatments, the number of beneficial anticipations (absolute errors less than 133 msec.) was significantly larger for intermediate than for minimal left-arm activity, supporting the view that proprioceptive feedback serves as a mediator in tasks requiring precise anticipation and timing.