Biomaterial Database

Characterization of wave I of the electrically evoked auditory brainstem response in the guinea pig. 1993

C A Miller, and P J Abbas, and B K Robinson

Department of Speech Pathology and Audiology, University of Iowa, Iowa City.

This paper examines the first component of the electrically evoked auditory brainstem response (EABR) of the guinea pig. Short (20 microseconds/phase) and long (4000 microseconds/phase) duration rectangular current pulses were applied through a bipolar intracochlear electrode in acute preparations. Short-duration pulses evoked a synchronized response relatively free of stimulus artifact; long pulses facilitated examination of the integrative capacities of nerve fibers at relatively low current levels. In deafened control subjects, wave I of the EABR consistently demonstrated two positive peaks having different latency-level and adaptation recovery functions. The early component (wave Ia) showed less decrement in latency with increasing stimulus level and recovered faster in a forward-masking paradigm. Non-monotonicities in the adaptation recovery curves were also observed, more consistently in the wave Ib data. It is proposed that wave Ia arises from stimulation of the axons proximal to the spiral ganglion while wave Ib is initiated at the peripheral dendritic processes. Implications for human cochlear implant research are discussed.

UI	MeSH Term	Description	Entries
D007612	Kanamycin	Antibiotic complex produced by Streptomyces kanamyceticus from Japanese soil. Comprises 3 components: kanamycin A, the major component, and kanamycins B and C, the minor components.	Kanamycin A,Kanamycin Sulfate,Kantrex
D009410	Nerve Degeneration	Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.	Neuron Degeneration,Degeneration, Nerve,Degeneration, Neuron,Degenerations, Nerve,Degenerations, Neuron,Nerve Degenerations,Neuron Degenerations
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
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
D006198	Hair Cells, Auditory	Sensory cells in the organ of Corti, characterized by their apical stereocilia (hair-like projections). The inner and outer hair cells, as defined by their proximity to the core of spongy bone (the modiolus), change morphologically along the COCHLEA. Towards the cochlear apex, the length of hair cell bodies and their apical STEREOCILIA increase, allowing differential responses to various frequencies of sound.	Auditory Hair Cells,Cochlear Hair Cells,Auditory Hair Cell,Cell, Cochlear Hair,Cells, Cochlear Hair,Cochlear Hair Cell,Hair Cell, Auditory,Hair Cell, Cochlear,Hair Cells, Cochlear
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000159	Vestibulocochlear Nerve	The 8th cranial nerve. The vestibulocochlear nerve has a cochlear part (COCHLEAR NERVE) which is concerned with hearing and a vestibular part (VESTIBULAR NERVE) which mediates the sense of balance and head position. The fibers of the cochlear nerve originate from neurons of the SPIRAL GANGLION and project to the cochlear nuclei (COCHLEAR NUCLEUS). The fibers of the vestibular nerve arise from neurons of Scarpa's ganglion and project to the VESTIBULAR NUCLEI.	Cranial Nerve VIII,Eighth Cranial Nerve,Cochleovestibular Nerve,Statoacoustic Nerve,Cochleovestibular Nerves,Cranial Nerve VIIIs,Cranial Nerve, Eighth,Cranial Nerves, Eighth,Eighth Cranial Nerves,Nerve VIIIs, Cranial,Nerve, Cochleovestibular,Nerve, Eighth Cranial,Nerve, Statoacoustic,Nerve, Vestibulocochlear,Nerves, Cochleovestibular,Nerves, Eighth Cranial,Nerves, Statoacoustic,Nerves, Vestibulocochlear,Statoacoustic Nerves,VIIIs, Cranial Nerve,Vestibulocochlear Nerves