Efference and the Conscious Perception of Movement

Abstract

Evidence was sought implicating efference in the conscious perception of movement by having subjects (n = 10) scale the time course of an active (efference present) and passive (efference absent) thumb movement Efference would presumably lead slightly in time the proprioceptive feedback from a movement and therefore cause active movements to be judged as occurring earlier than passive movements. A probe stimulus (10-msec light flash) was interjected at various temporal locations during an auditorily cued thumb movement made under the two conditions. Subjects estimated the temporal location of the flash relative to the occurrence of the thumb movement. Active movements were estimated to occur on the average 43 msec earlier than passive movements (p<.005), suggesting that efference contributed to the conscious perception of the movement.