Perception. Motor theories Author: Elena Pasquinelli [INSTNICOD] Contributors: none Current version (on 2006-01-23) Theories of perception that assign to the motor experience a significant position in the explanation of perceptual phenomena are called ‘motor theories of perception’ (for an historical review of motor theories of perception, see [Viviani, 1990] and [Berthoz, 2002]). Motor theories of perception are compatible with the existence of internal representations, i.e. of movement; in particular they are not necessarily committed to the denial of the role of representations or computations in the case of “higher order” cognitive processes. Anyway, action and perception are conceived as directly linked as in the case of a sensory-motor loop, with no mediation of cognitive processes (the central processor positioned between the input and the output signals). An example of neurophysiological model for this closed relationship is represented by the functioning of mirror neurons. “Mirror neurons” is the name given to a particular group of neurons which are activated both by the execution and by the observation of some specific motor actions, as reaching and manipulating (see [Rizzolatti, 1996]). It is suggested by [Rizzolatti, 2001] that mirror neurons have a role in the imitation and understanding of perceived actions. The connection between performed actions and perceived actions is then direct, with no form of interpolated cognitive mediation. Motor theories movement.

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It is possible to distinguish two different claims within the assertion of a key role played by action in perception. The first claim is that action directs perception through the exploration of the environment: it is impossible to separate perception from action, since there is no perceptual activity without the movement of sensors and the active exploration of the environment. The second claim is that motor competences and motor acts shape the perceptual content.

As an example of the first claim of motor theories of perception, [Berthoz, 2002] proposes a theory of perception as simulated action: perceptual activity is not confined to the interpretation of sensory messages but anticipates the consequences of action, so it is internal simulation of action. Each time it is engaged in an action, the brain constructs hypotheses about the state of a variegated group of sensory captors throughout the movement; the brain of the skilled skier for example does not control the state of all the body captors in a continuous and permanent way, instead it internally simulates the trajectory and controls the state of a specified group of captors only intermittently. The ensemble of the captors that are implicated in the analysis of movement and space (movement of the body and of the environment) are particularly important for this task; they circumscribe what [Berthoz, 2002] calls the “sense of movement” or kinaesthesia (with a broader extension than the classic term kinaesthesia which included only the tactile captors located within the muscles, tendons and joints). When the product of the integration of the different kinds of captors that participate in the sense of movement is not coherent the brain suffers from perceptual and motor troubles to which perceptual illusions can offer a solution. In general, within the theory of the sense of movement, illusions can be considered as solutions that the brain creates when faced with discrepancies between sensory information and the internal pre-representations or anticipations. In the sensorimotor vision of perception [Noë, 2003; O'Regan & Noë, 2001], perceptual experiences depend upon sensorimotor acitivity: movement is necessary in order to perceive objects as unitary, coherent and present entities. Thus, action shapes the formal aspects of the perceptual content. In the frame of the ecological approach the aspect of perceptual content depends upon action. [Turvey, 1981]; [Gibson, 1979, 1966]; [Stoffregen & Bardy, 2001] emphasize the relevance of activity in defining the stimulus to be perceived and the structure of the animal-environment coupling. In fact, according to the ecological approach what we directly perceive is affordances, that is, possibilities for action [Turvey, 1981]; [Gibson, 1979]: the ‘walkability’ of a surface, the ‘sittability’ of a chair, etc.

References: Gibson, J. J. (1966). The senses considered as perceptual systems. Boston: Houghton Mifflin Company. Gibson, J. J. (1979). The ecological approach to visual perception.: Houghton Mifflin Co. Noë, A. (2003). Art as enaction. Available: http://www.interdisciplines.org/artcog/papers/8/10. O'Regan, K., & Noë, A. (2001). A sensorimotor account of vision and visual consciousness. Behavioral and Brain Sciences, 24(5), 939-1011. Rizzolatti, G., Fadiga, L., Gallese, V., & Fogassi, L. (1996). Premotor cortex and the recognition of motor actions. Cognitive brain research, 3, 131-141. Rizzolatti, G., Fogassi, L., & Gallese, V. (2001). Neurophysiological mechanisms underlying the understanding and imitation of action. Nature Reviews Neuroscience(2), 661-670. Stoffregen, T. A., & Bardy, B. G. (2001). On Specification and the Senses. Behavioral and Brain Sciences, 24(1). Turvey, M., Shaw, R. E., Reed, E. S., & Mace, W. M. (1981). Ecological Laws of Perceiving and Acting: In Reply to Fodor and Pylyshyn. Cognition, 9, 237-304. Viviani, P. (1990). Motor-perceptual interactions: the evolution of an idea. In M. Piattelli Palmarini (Ed.), Cognitive Sciences in Europe: Issues and trends (pp. 11-39): Golem.

Related items: Active perception/Vision Active perception/ Touch Dynamic touch Haptic perception Illusions Illusions/perception of dynamic events Movement Perception. Direct approaches: the sensorimotor approach Perception. Direct approaches: the ecological approach

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