Showing papers in "Hearing Research in 1982"

TL;DR: The results demonstrate that the COCB effect is postsynaptic, probably mediated by outer hair cells, and suggest that the normal cochlea contains an active biomechanical mechanism which reduces the damping of the cochlear-partition motion and is modulated by activating the efferents.

TL;DR: The main finding is that different sets of proteins compose the cytoskeleton in supporting cells and the mechanoreceptor structures of the sensory cells, whereas supporting cells, although rich in actin, did not reveal fimbrin.

TL;DR: Hair cells of Sprague-Dawley rats aged 2-33 months were counted in order to assess the magnitude, location and time course of cell degeneration, and no significant correlation was found between the magnitude of inner hair cell and ganglion cell losses.

TL;DR: This paper shows that segregation of units according to spontaneous activity produces a segregation of several other properties as well, and indicates that type II units are recorded from inhibitory interneurons in the DCN.

TL;DR: Monaural losses in hearing sensitivity induced by an intense pure tone could be reduced if an acoustic stimulus of the same frequency was simultaneously delivered to the other ear.

TL;DR: A new mechanism is proposed, one which is consistent with observations in the lizard and turtle preparations and in whichhair-cell resonances result from coupling of mechanical properties of hair-cell stereociliary-tectorial structures with electrical properties of the hair- cell membrane through a receptor membrane process that has bidirectional, mechanoelectric and electromechanical, transduction properties.

TL;DR: Alligator lizards exposed to 105 dB broadband noise for 24 h showed a 33 dB loss in hearing which was almost completely recovered 11 days after removal from the noise.

TL;DR: It was concluded that the ABR (1/3-octave filtered sine waves) is suitable for the determination of hearing thresholds and the assessment of hearing loss, at least in the high-frequency range.

TL;DR: Two-tone rate suppression was examined in the responses of single cochlear-nerve fibers in Mongolian gerbils and found that frequencies around the fiber CF were most affected (suppressed) by the presence of the second tone, and that the low-frequency tail of the tuning curve tended to shift toward the boundary of the suppression area below CF.

TL;DR: The directionality of the cat's pinna was studied by using the amplitude of the cochlear microphonic as a quantitative indicator of tympanic sound pressure level (SPL), which revealed the pinna produces up to 28 dB amplification of acoustic signals delivered 'on-axis'.

TL;DR: The relationships between N1 thresholds, single neuron tuning curves and hair cell damage are described and single spiral ganglion cell recordings were obtained.

TL;DR: Investigation of the effect of a 40 Hz tone on the threshold of the compound action potential confirmed data obtained from single units and found that activity evoked by tones around the characteristic frequency of the cell was suppressed during displacement of the basilar membrane towards scala tympani and enhanced in the opposite direction at 40 Hz intensities that had no effect on spontaneous activity.

TL;DR: It was found that superoxide dismutase exhibits a higher specific activity in a fraction of the cochlea that contains the organ of Corti than in most other neural tissues.

TL;DR: The data from cases stimulated at lower levels of charge density, i.e. 20-40 muC/cm2, suggest that these may be more feasible levels for safe chronic electrical stimulation in scala tympani.

TL;DR: The usefulness of temporal masking patterns as an intermediate value for the description of hearing sensations is confirmed.

TL;DR: Intensity functions, relating receptor depolarization to stimulus intensity level, were obtained for the IHCs and have a consistent quantitative form for frequencies equal to or less than the characteristic frequency of a cell.

TL;DR: These deaf cat preparations fairly efficiently model pathologies recorded in man and are highly predictable over an acceptable time frame, of practical value for experiments involving intracochlear electrical stimulation.

TL;DR: Noise exposure induced a significantly greater hearing loss in SH rats than in N rats; SH animals were more susceptible to noise than were young ones; no difference was seen between males and females.

TL;DR: The dynamic range over which fine intensity discrimination is possible has been reported to be largely unaffected by limitation of the spread of neuronal activity to neighbouring frequency regions by bandstop noise masking, but this is examined in the presence of a bandstop masking noise designed to be comparable to that employed in the psychophysical experiments.

TL;DR: The perilymphatic space of the guinea pig cochlea was perfused with various concentrations of Ca2+, Mg2+ and gentamicin and results are consistent with the previous hypothesis of a biphasic mechanism of aminoglycoside toxicity.

TL;DR: A microelectrode mapping survey was made of the auditory cortex of the acallosal marsupial possum Trichosurus vulpecula and an orderly representation of cochlear place was found in the cortex with high frequencies located dorsally and low frequencies more ventrally.

TL;DR: Echoes from large surfaces up to 4.5-5.0 meters away evoked CM potentials as high in amplitude as those elicited by emitted pulses, even when there was no Doppler shift.

TL;DR: Chinchillas were anesthetized with ketamine and endocochlear potential (EP) and potassium concentration in endolymph (Ke+) were determined and following injection of furosemide, a dose-related fall in EP and Ke+ was observed.

TL;DR: A new, improved surgical approach to the cochlear nucleus is developed in the gerbil by making a small hole in the lateral wall of the temporal bone located within the perimeter of the superior semicircular canal.

TL;DR: The immature auditory system appears to be fully capable of transducing low frequency stimuli, but not high frequencies, and the early development of basal regions in the cochlea is viewed as insuring the delivery of a wide range of frequencies to rostral segments of the auditory system.

TL;DR: It is concluded that low concentrations of aminoglycoside antibiotics have a dual action upon the sensory hair cells that increase the spontaneous activity by affecting the hair cell membrane and at the same time they impair the mechano-electric transduction process resulting in a large phase lag in the receptor potentials.

TL;DR: A comparison of Liouville-Green calculations and exact solutions of 2- and 3-dimensional cochlea models shows clearly why and how the response of the basilar membrane builds up to a maximum and which factors cause a turnover and a rapid decrease to occur, in both the long-wave and the short-wave cases.

TL;DR: Two new interrelated hypotheses on the functional organization of the organ of Corti result from the consideration of the cell biology of its receptor cells, one dealing with the possibility of electrotonic interaction between inner and outer hair cells and the other with a possible contributing source to acoustic emissions of cochlear origin that results from vesicular membrane turnover.

TL;DR: Temporal masking effects on brainstem evoked responses (BERs) were studied in normal human newborns and adults and it was found that forward masking prolonged the latencies of the newborn BERs significantly longer than adult B ERs.

TL;DR: The intensity--rate and intensity--latency functions were analyzed quantitatively from single auditory fibers in the eighth nerve of northern leopard frogs and the significance of the latency function on central binaural time processing was discussed.