In:
The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 35, No. 5_Supplement ( 1963-05-01), p. 809-809
Abstract:
An efferent cochlear bundle was demonstrated anatomically in the pigeon [Boord, Exptl. Neurol. 3, 225 (1961)]. We have developed techniques for stereotaxic stimulation thereof in pigeons prepared under Fluothane anesthesia and immobilized by transection of cervical spinal cord plus injection of Flaxedil. Responses to tone pips or clicks were recorded oscillographically from the exposed round window. When the testing sounds are preceded by delivery of, say, 30 shocks at 300/sec to the region of the efferent cochlear bundle close to the midline (histologically controlled), the cochlear microphonic (CM) potential is potentiated while the neural (N1) spike is reduced. These effects were titrated as equivalent dB changes in sound energy [cf., Desmedt, J. Acoust. Soc. Am. 34, 1478 (1962)] and they have not exceeded +6 dB equivalents for CM and −6 dB equivalents for N1. Corresponding figures for the cat's olivocochlear bundle are +4 dB equivalents for CM and −25 dB equivalents for N1 (Desmedt, loc. cit). The marked contrast in potency for gating out neural responses evoked by sound in these two species raises questions about (1) behavioral significance of efferent bundle in birds, and (2) mode of action on the inner ear. [This work was supported by Office of Aerospace Research, USAF, and by the National Institute of Neurological Diseases and Blindness, National Institutes of Health, Public Health Service, U. S. Department of Health, Education, and Welfare.]
Type of Medium:
Online Resource
ISSN:
0001-4966
,
1520-8524
Language:
English
Publisher:
Acoustical Society of America (ASA)
Publication Date:
1963
detail.hit.zdb_id:
1461063-2
Permalink