Typical action perception and interpretation without motor simulation


Vannuscorps, G., & Caramazza, A. (2016). Typical action perception and interpretation without motor simulation. Proceedings of the National Academy of Sciences , 113 (1), 86-91.


Every day, we interact with people synchronously, immediately understand what they are doing, and easily infer their mental state and the likely outcome of their actions from their kinematics. According to various motor simulation theories of perception, such efficient perceptual processing of othersactions cannot be achieved by visual analysis of the movements alone but requires a process of motor simulationan unconscious, covert imitation of the observed movements. According to this hypothesis, individ- uals incapable of simulating observed movements in their motor system should have difficulty perceiving and interpreting ob- served actions. Contrary to this prediction, we found across eight sensitive experiments that individuals born with absent or se- verely shortened upper limbs (upper limb dysplasia), despite some variability, could perceive, anticipate, predict, comprehend, and mem- orize upper limb actions, which they cannot simulate, as efficiently as typically developed participants. We also found that, like the typically developed participants, the dysplasic participants systematically per- ceived the position of moving upper limbs slightly ahead of their real position but only when the anticipated position was not biomechan- ically awkward. Such anticipatory bias and its modulation by implicit knowledge of the body biomechanical constraints were previously considered as indexes of the crucial role of motor simulation in action perception. Our findings undermine this assumption and the theories that place the locus of action perception and comprehension in the motor system and invite a shift in the focus of future research to the question of how the visuo-perceptual system represents and pro- cesses observed body movements and actions. 

Last updated on 03/22/2016