Linked Life Data

10913884

Source:http://linkedlifedata.com/resource/pubmed/id/10913884

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2000-9-18
pubmed:abstractText
High rate intracochlear electrical stimulation at high intensities can induce significant reductions in the excitability of the auditory nerve as measured by a decrement in the amplitude of the electrically evoked auditory brainstem response (EABR). Such changes are primarily associated with stimulus induced neuronal activity, although direct current (DC) can also contribute. We examined the extent of stimulus induced change in auditory nerve excitability using large surface area platinum electrodes ('high-Q' electrodes). These electrodes have a surface area approximately 70 times greater than standard Pt electrodes of the same geometric area, resulting in lower DC and charge density (charge/electrode surface area) for a common stimulus. Guinea pigs were bilaterally implanted with either high-Q or standard Pt electrodes, and unilaterally stimulated for 2 h using stimulus intensities of 12 dB or 20-30 dB above EABR threshold (0.34 microC/phase) at stimulus rates of 200, 400, or 1000 pulses per second (pps). EABRs were recorded before and following the acute stimulation. While there were significant reductions in EABR amplitudes and elevated EABR thresholds following stimulation at 12 dB above threshold using 400 and 1000 pps delivered to standard Pt electrodes, there were fewer or no significant changes in the post-stimulus EABR amplitude and threshold using high-Q electrodes under equivalent stimulus conditions. At a higher stimulus intensity (20-30 dB above EABR threshold), no reduction in EABR amplitude was observed at 200 pps for both stimulating electrodes. However, EABRs were reduced significantly at 400 and 1000 pps. There was significantly greater EABR recovery following stimulation using high-Q electrodes compared with standard Pt electrodes at 400 (P<0.05) and 1000 pps (P<0.05). These data indicate that large surface area electrodes can significantly reduce stimulus induced changes in auditory nerve excitability, and may therefore have important clinical application.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0378-5955
pubmed:author
pubmed:issnType
Print
pubmed:volume
146
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
57-71
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Reduction in excitability of the auditory nerve following electrical stimulation at high stimulus rates: V. Effects of electrode surface area.
pubmed:affiliation
Department of Otolaryngology, University of Melbourne, CRC for Cochlear Implant and Hearing Aid Innovation, 32 Gisborne Street, 3002, East Melbourne, Vic., Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't