From Big Medical Encyclopedia

BLINKING — bystry short-term smykaniye and disconnection century; one of forms of defense reactions of an organism consisting in protection of eyes from the damaging mechanical, light or chemical influence. The m is carried out due to strengthening of a centrifugal impulsation on fibers of the facial nerve causing reduction of a circular muscle eyes (see). At mechanical or chemical irritation of a conjunctiva of an eye of M. arises in 40 — 70 ms after the beginning of influence. The m arises on strong or unexpected irritations of visual, acoustical and other receptors (a so-called blink reflex). After formation of conditioned connections of M. it is developed in response to an alarm irritant, advancing the supporting influence that found application during the studying of century of N of of the person.

The m is used as diagnostic test for definition of a condition of c. N of page of the person. So, in particular, M. is absent at defeat front (a hare eye, a lagophthalmia) or a trifacial and is slowed down

(urezhatsya) at defeat of structures of a myelencephalon and the bridge of a brain (parkinsonism), and also at a bazedovy disease (a symptom of Shtellvaga). The strengthened M. arises as a result of irritation of a mucous membrane of an eye (conjunctivitis, a blepharitis, etc.), at increase in excitability of separate structures of a brain (hysteria) and in other cases.

See also Defense reactions of an organism .

Bibliography: Galperin S. I. and Tatar A. E. Techniques of a research of higher nervous activity of the person and animals, M., 1973; X about d about with X. G. Nervous diseases, M., 1974.

Yu. V. Uryvayev.