Toward Robot-Assisted Psychosocial Techniques for Sound Stimulation of Children Born with Hearing Loss

Sound stimulation of the tympanic organ of Locusta migratoria and Schistocerca gregaria initiates responses in the tympanic nerve and these in turn stimulate a few interneurones which ascend the ventral cord from the metathoracic ganglion to the brain. Some of the preparations show the following evidence of pitch discrimination. The response of the whole tympanic nerve to a pulsed note of low pitch cannot be made identical to the response to the same pulse at high pitch no matter how the relative intensities are adjusted. A continuous note, which presumably adapts some but not all of the primary receptors, modifies the relation between pre- and post-ganglionic responses in a way which depends on the pitch of the continuous note. The relative intensities of a pure tone of high pitch (10 to 15 kc/s) and one of low pitch (0.5 to 2.0 kc/s) can, in a preparation showing only ‘on' responses, be adjusted so that there is a post-ganglionic response to the former but not to the latter, although the latter causes a larger response in the tympanic nerve. Certain large interneurones, identifiable by their spike height, do not have the same curve of threshold to pulses of various pitch as does the summed response from the whole tympanic nerve. The post-ganglionic response is, therefore, towards a selected fraction of the sensory axons. In each of the above tests the effects are small and pitch discrimination cannot be of great significance for the life of the animal.

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Brain Stem Auditory Evoked Response

Annals of Otology Rhinology & Laryngology ◽

10.1177/00034894790880s402 ◽

1979 ◽

Vol 88 (4_suppl) ◽

pp. 11-21 ◽

Cited By ~ 5

Author(s):

Kevin T. Kavanagh ◽

James V. Beardsley

Keyword(s):

Hearing Loss ◽

Brain Stem ◽

Normal Wave ◽

Sound Intensity ◽

Evoked Response ◽

Sound Stimulation ◽

Auditory Evoked Response ◽

Occult Lesion ◽

Intensity Functions ◽

Wave Latency

This paper studies the effect of otologic disease on the brain stem auditory evoked response (BAER). Both conductive and neurosensory hearing losses are analyzed by plotting wave V latencies and amplitudes as a function of sound intensity. It was found that the BAER is elicited primarily by frequencies greater than 2000 Hz. Conductive hearing losses produce a latency intensity function which approaches the norm with high decibel stimulation. Neurosensory losses produce a variety of latency intensity functions. In determining the degree of hearing loss, wave threshold is found to be the best index. Wave latency at high decibels is found to have little correspondence to degree of neurosensory loss; wave amplitude is highly variable among subjects but still a useful indicator for detecting pathology. Between-ear comparisons of wave latencies elicited by high decibel sound stimulation suggest that unilateral nonrecruiting or partially recruiting hearing losses will result in a latency difference. This method can be used to detect unilateral acoustic neuromas, and the false positives found by this technique are probably caused by other unilateral nonrecruiting hearing losses. In evaluating neurological disease, and especially when testing for a second occult lesion in multiple sclerosis (MS) an audiogram should be obtained because the criterion of a normal wave latency with decreased amplitude for the diagnosis of MS can be mimicked by peripheral hearing loss.

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Physiological basis of noise-induced hearing loss in a tympanal ear

10.1101/698670 ◽

2019 ◽

Author(s):

Ben Warren ◽

Georgina E Fenton ◽

Elizabeth Klenschi ◽

James FC Windmill ◽

Andrew S French

Keyword(s):

Hearing Loss ◽

Ion Channels ◽

Noise Exposure ◽

Noise Induced Hearing Loss ◽

Auditory Neurons ◽

Supporting Cells ◽

Physiological Basis ◽

Positive Ions ◽

Induced Changes ◽

Stimulation Of

AbstractAcoustic overexposure, such as listening to music too loud and too often, results in noise-induced hearing loss. The pathologies of this prevalent sensory disorder begin in the synapses of the primary auditory receptors, their postsynaptic partners and supporting cells. The extent of noise-induced damage, however, is determined by over-stimulation of primary auditory receptors. When over-stimulated, an excessive amount of positive ions flood into the primary auditory receptors, triggering the activation of ion channels and possibly disrupting their ability to encode sound. A systematic characterisation of the electrophysiological function of primary auditory receptors is warranted to understand how noise-exposure impacts on downstream targets, where the pathologies of hearing loss begin. Here, we used the experimentally-accessible locust ear to characterise noise-induced changes in the auditory receptors. Although, we found a decrease in ability of the primary auditory neurons to encode sound, this is probably due to pathologies of their supporting cells.

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Round Window Stimulation of the Cochlea

Frontiers in Neurology ◽

10.3389/fneur.2021.777010 ◽

2021 ◽

Vol 12 ◽

Author(s):

Herman A. Jenkins ◽

Nathaniel Greene ◽

Daniel J. Tollin

Keyword(s):

Hearing Loss ◽

Mechanical Stimulation ◽

Round Window ◽

Ossicular Chain ◽

External Ear ◽

Ear Canal ◽

Hearing Rehabilitation ◽

Mixed Hearing Loss ◽

Conductive Mechanism ◽

Stimulation Of

Mixed hearing loss associated with a sensorineural component and an impaired conductive mechanism for sound from the external ear canal to the cochlea represents a challenge for rehabilitation using either surgery or traditional hearing amplification. Direct stimulations of the ossicular chain and the round window (RW) membrane have allowed an improved hearing in this population. The authors review the developments in basic and clinical research that have allowed the exploration of new routes for inner ear stimulation. Similar changes occur in the electrophysiological measures in response to auditory stimulation through the traditional route and direct mechanical stimulation of the RW. The latter has proven to be very effective as a means of hearing rehabilitation in a group of patients with significant difficulties with hearing and communication.

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