In physiology, an efference copy or efferent copy is an internal copy of an outflowing (efferent), movement-producing signal generated by an organism's motor system.[1] It can be collated with the (reafferent) sensory input that results from the agent's movement, enabling a comparison of actual movement with desired movement, and a shielding of perception from particular self-induced effects on the sensory input to achieve perceptual stability.[1] Together with internal models, efference copies can serve to enable the brain to predict the effects of an action.[1]
An equal term with a different history is corollary discharge.[2]
Efference copies are important in enabling motor adaptation such as to enhance gaze stability. They have a role in the perception of self and nonself electric fields in electric fish. They also underlie the phenomenon of tickling.
- ^ a b c Jeannerod, Marc (2003): "Action Monitoring and Forward Control of Movements". In: Michael Arbib (Ed.), The Handbook of Brain Theory and Neural Networks. Second Edition. Cambridge, Mass.: MIT Press, pp. 83–85, here: p. 83.
- ^ Gyr John W (1972). "Is a Theory of Direct Visual Perception Adequate?". Psychological Bulletin. 77 (4): 246–261 [250]. doi:10.1037/h0032352. PMID 5017819.