Biomaterial Database

Psychophysical measures from electrical stimulation of the human cochlear nucleus. 1990

R V Shannon, and S R Otto

House Ear Institute, Los Angeles, California 90057.

Auditory performance on basic psychophysical tasks was measured in ten deaf patients with electrodes positioned near their cochlear nucleus. The device is called the auditory brainstem implant (ABI). Electrodes were placed during surgery to remove an acoustic neuroma, which results in the removal of the VIII nerve and, thus deafness. In patients who received auditory sensation from electrical stimulation we measured auditory performance on standard psychophysical tasks: thresholds, loudness growth, intensity discrimination, temporal integration, temporal modulation detection, gap detection, and forward masking. Plots of threshold as a function of frequency or biphasic pulse duration were markedly different from those of patients with cochlear implants. The difference in threshold functions is probably partly due to the biophysical difference in the neural elements stimulated. Another possibility is that part of the difference is due to the highly abnormal spatial pattern of activation in the cochlear nucleus from electrical stimulation, which prevents normal spatial integration of activity. The usable range of electrical amplitudes above threshold is comparable with that of cochlear implants, typically 10-15 dB. Little temporal integration occurs over a range of stimulus durations from 2-1000 ms. When compared at equivalent loudness levels, gap detection thresholds are similar to, or a bit longer than, gap thresholds in normal-hearing listeners and cochlear implant patients. Forward masking recovery functions are similar to those of normal listeners and cochlear implant patients. Patients' ability to detect amplitude modulation as a function of modulation frequency is similar to that of cochlear implant patients and normal listeners. Thus, direct electrical stimulation of the brainstem produces temporal resolution that does not significantly differ from that of normal listeners when compared in equivalent amplitude units. This implies that the limiting factors for these tasks are more centrally located, and not directly related to threshold mechanisms. Thus, a properly designed speech processor could preserve the important temporal features of speech for these patients.

UI	MeSH Term	Description	Entries
D008144	Loudness Perception	The perceived attribute of a sound which corresponds to the physical attribute of intensity.	Loudness Perceptions,Perception, Loudness,Perceptions, Loudness
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009464	Neuroma, Acoustic	A benign SCHWANNOMA of the eighth cranial nerve (VESTIBULOCOCHLEAR NERVE), mostly arising from the vestibular branch (VESTIBULAR NERVE) during the fifth or sixth decade of life. Clinical manifestations include HEARING LOSS; HEADACHE; VERTIGO; TINNITUS; and FACIAL PAIN. Bilateral acoustic neuromas are associated with NEUROFIBROMATOSIS 2. (From Adams et al., Principles of Neurology, 6th ed, p673)	Acoustic Neuroma,Melanocytic Vestibular Schwannoma,Schwannoma, Acoustic,Schwannoma, Vestibular,Acoustic Neuroma, Cerebellopontine Angle,Acoustic Tumor,Angle Tumor,Cerebellopontine Angle Acoustic Neuroma,Cerebellopontine Angle Tumor,Neurilemmoma, Acoustic,Neurilemoma, Acoustic,Neurinoma of the Acoustic Nerve,Neurinoma, Acoustic,Neuroma, Acoustic, Unilateral,Vestibular Schwannoma,Acoustic Neurilemmoma,Acoustic Neurilemmomas,Acoustic Neurilemoma,Acoustic Neurilemomas,Acoustic Neurinoma,Acoustic Neurinomas,Acoustic Neuromas,Acoustic Schwannoma,Acoustic Schwannomas,Acoustic Tumors,Angle Tumor, Cerebellopontine,Angle Tumors,Angle Tumors, Cerebellopontine,Cerebellopontine Angle Tumors,Melanocytic Vestibular Schwannomas,Neurilemmomas, Acoustic,Neurilemomas, Acoustic,Neurinomas, Acoustic,Neuromas, Acoustic,Schwannoma, Melanocytic Vestibular,Schwannomas, Acoustic,Schwannomas, Melanocytic Vestibular,Schwannomas, Vestibular,Tumor, Acoustic,Tumor, Angle,Tumor, Cerebellopontine Angle,Tumors, Acoustic,Tumors, Angle,Tumors, Cerebellopontine Angle,Vestibular Schwannoma, Melanocytic,Vestibular Schwannomas,Vestibular Schwannomas, Melanocytic
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
D011571	Psychoacoustics	The science pertaining to the interrelationship of psychologic phenomena and the individual's response to the physical properties of sound.	Psychoacoustic
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
D003054	Cochlear Implants	Electronic hearing devices typically used for patients with normal outer and middle ear function, but defective inner ear function. In the COCHLEA, the hair cells (HAIR CELLS, VESTIBULAR) may be absent or damaged but there are residual nerve fibers. The device electrically stimulates the COCHLEAR NERVE to create sound sensation.	Auditory Prosthesis,Cochlear Prosthesis,Implants, Cochlear,Auditory Prostheses,Cochlear Implant,Cochlear Prostheses,Implant, Cochlear,Prostheses, Auditory,Prostheses, Cochlear,Prosthesis, Auditory,Prosthesis, Cochlear
D003638	Deafness	A general term for the complete loss of the ability to hear from both ears.	Deafness Permanent,Hearing Loss Permanent,Prelingual Deafness,Deaf Mutism,Deaf-Mutism,Deafness, Acquired,Hearing Loss, Complete,Hearing Loss, Extreme,Acquired Deafness,Complete Hearing Loss,Deafness, Prelingual,Extreme Hearing Loss,Permanent, Deafness,Permanent, Hearing Loss,Permanents, Deafness
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical