SHVABAH EXPERIENCE (D. Schwabach, is mute. the otorhinolaryngologist, 1846 — 1920) — a method of differential diagnosis of defeat of the acoustic analyzer by comparison of bone conductivity at the sick and healthy person at a research a tuning fork of C128 (128 fluctuations in 1 second). The method is offered by Shvabakh in 1885.
The leg of the tuning fork making fluctuations is put to the middle of parietal area or to a mastoid of the patient (in the latter case usually separately investigate bone conductivity of each ear) and include a stop watch. The moment when the patient ceases to hear a sound, note on a stop watch, and the doctor at once moves a leg of a tuning fork to himself (provided that it has obviously normal hearing) respectively to the parietal area or on a mastoid and notes duration of time to a full zatikhaniye of a sound of a tuning fork. If after such transfer of a tuning fork the doctor does not hear his sound, then experiment is repeated upside-down, i.e. in the beginning the doctor investigates bone conductivity at himself, and then at the patient.
At menyiyeny durations of perception of a sound of a tuning fork by the patient in comparison with the healthy person increase — about defeat of the sound carrying out device demonstrates defeat at it the sound perceiving device («shvaba it is shortened») («shvaba it is extended»). If inspected and the doctor hear a sound of a tuning fork during the same time, it testifies to normal hearing at inspected («shvaba normal»).
SHVARTTSMAN the PHENOMENON 373
For specification of the results received by means of Sh. by the lake is used by Weber and Rinne's methods (see Weber experience, Rinne experience). In recent years there were more perfect methods of a research of the acoustic analyzer. To them the audiometriya and measurement of acoustical sensitivity belong to ultrasound (see Relative deafness).
See also Hearing.
Bibliography: Denker A.
and Al Brecht Century. The textbook of diseases of an ear, upper respiratory tracts and an oral cavity, the lane e is mute., page 61, L. — M, 1936; Yermolaev V. G. and Levin A. L. Practical audiology, page 55, L., 1969;
Undrits V. F., Temkin Ya. S. and Neumann L. V. Guide to a clinical audiology, page 107, M., 1962;
Schwabach D. Ueber den Werth des Rinne’schen Versuches fur die Diagnostik der Gehorkrankheiten, Z. Ohrenheilk., Bd 14, S. 61, 1885. V. P. Gamov.