Biomaterial Database

Efferent tracts and cochlear frequency selectivity. 1986

P Bonfils, and M C Remond, and R Pujol

The cochlear innervation of guinea pigs was sectioned medially in a rostrocaudal direction at the level of the floor of the fourth ventricle, to study the effects of efferent pathways on cochlear microphonic (CM) suppression, the compound action potential (CAP) masking phenomenon, the input-output CAP function, and cochlear frequency selectivity estimated with tuning curves of single auditory nerve fibers. Sectioning reduced CM suppression without having any effect on absolute CM amplitude; it also reduced CAP masking. The input-output CAP function was not changed at intensities below 75 dB, and the single-unit tuning curves recorded before and after nerve sectioning were unaffected. Thus, the crossed efferent tracts (i.e., mainly the medial system) seems to be involved in the masking function itself, rather than one of the mechanisms responsible for high frequency cochlear selectivity.

UI	MeSH Term	Description	Entries
D009433	Neural Inhibition	The function of opposing or restraining the excitation of neurons or their target excitable cells.	Inhibition, Neural
D010470	Perceptual Masking	The interference of one perceptual stimulus with another causing a decrease or lessening in perceptual effectiveness.	Masking, Perceptual,Maskings, Perceptual,Perceptual Maskings
D002552	Cerebral Ventricles	Four CSF-filled (see CEREBROSPINAL FLUID) cavities within the cerebral hemispheres (LATERAL VENTRICLES), in the midline (THIRD VENTRICLE) and within the PONS and MEDULLA OBLONGATA (FOURTH VENTRICLE).	Foramen of Monro,Cerebral Ventricular System,Cerebral Ventricle,Cerebral Ventricular Systems,Monro Foramen,System, Cerebral Ventricular,Systems, Cerebral Ventricular,Ventricle, Cerebral,Ventricles, Cerebral,Ventricular System, Cerebral,Ventricular Systems, Cerebral
D003051	Cochlea	The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.	Cochleas
D003055	Cochlear Microphonic Potentials	The electric response of the cochlear hair cells to acoustic stimulation.	Cochlear Microphonic Potential,Potential, Cochlear Microphonic,Potentials, Cochlear Microphonic
D004525	Efferent Pathways	Nerve structures through which impulses are conducted from a nerve center toward a peripheral site. Such impulses are conducted via efferent neurons (NEURONS, EFFERENT), such as MOTOR NEURONS, autonomic neurons, and hypophyseal neurons.	Motor Pathways,Efferent Pathway,Pathway, Efferent,Pathways, Efferent
D005072	Evoked Potentials, Auditory	The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.	Auditory Evoked Potentials,Auditory Evoked Response,Auditory Evoked Potential,Auditory Evoked Responses,Evoked Potential, Auditory,Evoked Response, Auditory,Evoked Responses, Auditory,Potentials, Auditory Evoked
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D000161	Acoustic Stimulation	Use of sound to elicit a response in the nervous system.	Auditory Stimulation,Stimulation, Acoustic,Stimulation, Auditory
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia