Generally speaking, the active process of recognizing and identifying something. As such, it is distinguished from sensation, the sensitivity of neural receptors to internal and external stimuli. Putting the two terms together, perception is then a process of converting ‘meaningless’ sensations into ‘meaningful’ percepts. This interpretation represents the concept of indirect perception that can be traced back to the work of Hermann L.F. Helmholtz (1821-1894). The process of converting sensation into perception is achieved by a sequence of stages, one or more of which is dedicated to information processing. A simplified schematic representation of these stages is given in the following figure.
Indirect perception stages in visually perceiving an object. From Gibson, J.J. (1979). The ecological approach to visual perception. Hillsdale: N.J. Erlbaum.
This concept is opposed by that of direct perception as espoused by James J. Gibson (1904-1979) and his followers in ecological psychology based on the principle of mutuality between perception and action, this principle being most clearly expressed in his notion of affordances: all the information necessary for accurate perception is contained in the environment, perception is immediate and spontaneous, and perception and action cannot be separated as perception guides action and action generates more new perceptual information. In comparison, Gestalt psychology, although not associated with a theory of indirect perception as just described, can be depicted as studying perception by means of a motionless observer looking at a motionless scene. A controversial point about Gibson’s theorizing is that he treats perceptual systems as active, unbiased samplers of information that can be directly an veridically picked up in the external world. According to Roy W. Sellars (1973) in his book Neglected alternatives, it can be termed presentationalism in contrast to representationalism that characterises the more traditional theories of perception based on indirect perception. Presentationalism is direct realism in which environmental properties are directly perceived without any psychological mediation. Representationalism is indirect realism in which order (meaning) is imposed on sensations by a series of inference-making processes. An attempt to integrate these two concepts and also cognition with perception was attempted by Ulric Neisser (1976) in his book Cognition and reality based on his three-part perception-action cycle schemata (past knowledge directs perception to task-relevant stimuli), perceptual exploration (sampling and selection of available information relevant to completion of the task), and schemata modification (arising from discrepancies between information obtained and information in the schemata).
See Affordance, Attention, Biological motion, Cognition, Cognitive science, Direct realist account, Ecological psychology, Form perception, Gustation, Homunculus problem, Locomotion, Motion perception, Olfaction, Intersensory redundancy hypothesis, Organism-environment mutuality, Perception-action coupling, Perceptual development, Point-light display, Stochasticity, Two visual systems hypothesis