Orienting Reflex(redirected from investigatory reflex)
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(also focusing reflex, investigatory reflex, Pavlov’s “What-is-it?” reflex), in animals and man, a complex of responses in various body systems that is caused by any unexpected change of situation and is conditioned by special activity of the central nervous system.
Changes in the functioning of the central and autonomic nervous systems during the orienting reflex are directed toward mobilizing the body’s analyzing and motor systems, thus promoting rapid and accurate evaluation of a new situation and elaboration of a new, nonautomatic action. Suppression of preceding activity and turning of the head (ears, eyes) toward the stimulus occur simultaneously. The orienting reflex is accompanied by an increase of adrenalin in the blood, a change in the electric potential of the skin (galvanic skin reflex), an activation reaction (in the form of desynchronization of the slow electrical activity of the cerebral cortex), and a number of other phenomena that characterize preparation of the body for actions in a new situation. Functions that do not participate in such actions, such as digestion, are inhibited. When the change in the situation is accompanied by an unconditioned stimulus, that is, when it is reinforced by the stimulus, a conditioned reflex may develop on the basis of the orienting reflex; an indifferent stimulus becomes essential and meaningful to the organism. If a neutral stimulus keeps recurring, the orienting reflex is no longer evoked.
The orienting reflex plays an important role in organizing higher nervous activity in animals and humans. According to modern conceptions, the bases for the orienting response are activating influences of the reticular formation on the higher sections of the central nervous system. Along with this, the level of excitability of corresponding zones of the cerebral cortex is raised substantially, thus creating favorable conditions for the formation of a conditioned-reflex chain in the cortex.
In humans the orienting reflex participates in acts of varying degrees of complexity, from a reaction to any new agent to the most complex mental work, for example, when a person, confronted by an unexpected fact or thought, concentrates and mobilizes himself to comprehend it. The basis for the attention that arises in this situation is the orienting response, which appears, according to V. M. Bekhterev, in the form of the “concentration reflex.”
The role of the orienting response in human mental activity is more fully revealed when that activity is disturbed, for example, with schizophrenia. Loss of the orienting reflex, or its extinction with repeated stimuli, significantly decreases the possibility of adapting to new conditions. In other cases, the presence of the inhibiting component of the orienting reflex and the absence of the investigative component make it impossible to analyze a new situation and react to it adequately.
REFERENCESPavlov, I. P. Polnoe sobranie sochinenii, 2nd ed., vol. 3, books 1–2. Moscow-Leningrad, 1951.
Orientirovochnyi refleks i orientirovochno-issledovatel’skaia deiatel’nost’. Moscow, 1958.
Magoun, H. Bodrstvuiushchii mozg. Moscow, 1961. (Translated from English.)
Chauvin, R. Povedenie zhivotnykh, chapter 6. Moscow, 1972. (Translated from French.)
N. D. AGRACHEVA