Intracochlear and extracochlear ECAPs suggest antidromic action potentials

Charles A Miller; Paul J Abbas; Marcia J Hay-McCutcheon; Barbara K Robinson; Kirill V Nourski; Fuh-Cherng Jeng

doi:10.1016/j.heares.2004.07.005

Back

Intracochlear and extracochlear ECAPs suggest antidromic action potentials

Journal article

Peer reviewed

Intracochlear and extracochlear ECAPs suggest antidromic action potentials

Charles A Miller, Paul J Abbas, Marcia J Hay-McCutcheon, Barbara K Robinson, Kirill V Nourski and Fuh-Cherng Jeng

Hearing research, Vol.198(1), pp.75-86

2004

DOI: 10.1016/j.heares.2004.07.005

PMID: 15567605

View Online

Abstract

With experimental animals, the electrically evoked compound action potential (ECAP) can be recorded from multiple sites (e.g., round window, intracranial and intracochlear sites). However, human ECAPs are typically recorded from intracochlear electrodes of the implanted array. To bridge this difference, we obtained ECAPs from cats using both intracochlear and nerve-trunk recording sites. We also sought to determine how recording the site influences the acquired evoked potential and how those differences may provide insight into basic excitation properties. In the main experiment, ECAPs were recorded from four acutely deafened cats after implanting a Nucleus-style banded electrode array. Potentials were recorded from an electrode positioned on the nerve trunk and an intracochlear electrode. We manipulated stimulus level, electrode configuration (monopolar vs bipolar) and stimulus polarity, variables that influence the site of excitation. Intracochlear ECAPs were found to be an order of magnitude greater than those obtained with the nerve-trunk electrode. Also, compared with the nerve-trunk potentials, the intracochlear ECAPs more closely resembled those obtained from humans in that latencies were shorter and the waveform morphology was typically biphasic (a negative peak followed by a positive peak). With anodic monophasic stimuli, the ECAP had a unique positive-to-negative morphology which we attributed to antidromic action potentials resulting from a relatively central site of excitation. We also collected intracochlear ECAPs from twenty Nucleus 24 implant users. Compared with the feline ECAPs, the human potentials had smaller amplitudes and longer latencies. It is not clear what underlies these differences, although several factors are considered.

Electrical stimulation

Cochlear implant

Compound action potential

Antidromic

Auditory nerve

Cat

Details

Title: Subtitle: Intracochlear and extracochlear ECAPs suggest antidromic action potentials
Creators: Charles A Miller - Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, 21201 PFP, 200 Hawkins Drive, Iowa City, IA 52242, USA
Paul J Abbas - Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, 21201 PFP, 200 Hawkins Drive, Iowa City, IA 52242, USA
Marcia J Hay-McCutcheon - Department of Speech Pathology and Audiology, University of Iowa, Iowa City, IA 52242, USA
Barbara K Robinson - Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, 21201 PFP, 200 Hawkins Drive, Iowa City, IA 52242, USA
Kirill V Nourski - Department of Otolaryngology, Head and Neck Surgery, University of Iowa Hospitals and Clinics, 21201 PFP, 200 Hawkins Drive, Iowa City, IA 52242, USA
Fuh-Cherng Jeng - Department of Speech Pathology and Audiology, University of Iowa, Iowa City, IA 52242, USA
Resource Type: Journal article
Publication Details: Hearing research, Vol.198(1), pp.75-86
DOI: 10.1016/j.heares.2004.07.005
PMID: 15567605
NLM abbreviation: Hear Res
ISSN: 0378-5955
eISSN: 1878-5891
Publisher: Elsevier B.V
Language: English
Date published: 2004
Academic Unit: Communication Sciences and Disorders; Iowa Neuroscience Institute; Neurosurgery; Otolaryngology
Record Identifier: 9984040357302771

Metrics

13 Record Views

40 Times Cited - Web of Science

See more details