Journal article
Electrically evoked compound action potentials of guinea pig and cat: responses to monopolar, monophasic stimulation
Hearing research, Vol.119(1), pp.142-154
05/01/1998
DOI: 10.1016/S0378-5955(98)00046-X
PMID: 9641327
Abstract
We recorded electrically evoked compound action potentials (EAPs) from guinea pigs and cats using monophasic current pulses delivered by a monopolar intracochlear electrode. By using simple stimuli, we sought results that could shed light on basic excitation properties of the auditory nerve. In these acute experiments, the recording electrode was placed directly on the auditory nerve. Responses to anodic and cathodic stimulus pulses were recorded separately to evaluate stimulus polarity effects. Several polarity-dependent properties were observed. Both EAP morphology and latency were polarity-dependent, with greater latencies for cathodic stimulation. Threshold stimulus level was also polarity-dependent, but in different directions in the two species: cats had lower cathodic thresholds while guinea pigs had lower anodic thresholds. We also observed that the slopes of the EAP amplitude-level functions depended upon stimulus polarity. In most cases where EAP saturation amplitude could be measured, that amplitude was similar for anodic and cathodic stimuli, suggesting that either stimulus polarity can recruit all fibers, or at least a comparable numbers of fibers. The common findings (e.g., EAP morphology and polarity-dependent latency) observed in these two species suggest results that can be extrapolated to responses obtained in humans, while the species-specific findings (e.g., dependence of threshold on polarity) may point to underlying anatomical differences that caution against overgeneralization across species. Some of our observations also bear upon hypotheses of how electrical stimuli may excite different sites on auditory nerve fibers.
Details
- Title: Subtitle
- Electrically evoked compound action potentials of guinea pig and cat: responses to monopolar, monophasic stimulation
- Creators
- Charles A Miller - Department of Otolaryngology - Head and Neck Surgery, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, C-21 GH, Iowa City, IA 52242, USAPaul J Abbas - University of IowaJay T Rubinstein - University of IowaBarbara K Robinson - University of IowaAkihiro J Matsuoka - University of IowaGeorge Woodworth - University of Iowa
- Resource Type
- Journal article
- Publication Details
- Hearing research, Vol.119(1), pp.142-154
- Publisher
- Elsevier B.V
- DOI
- 10.1016/S0378-5955(98)00046-X
- PMID
- 9641327
- ISSN
- 0378-5955
- eISSN
- 1878-5891
- Language
- English
- Date published
- 05/01/1998
- Academic Unit
- Statistics and Actuarial Science; Biostatistics; Otolaryngology
- Record Identifier
- 9984383310502771
Metrics
4 Record Views