Physiological properties of the electrically stimulated auditory nerve. II. Single fiber recordings

Honert, Chris van den; Stypulkowski, Paul H.

doi:10.1016/0378-5955(84)90052-2

Cited by 234 publications

(123 citation statements)

References 17 publications

Supporting

Mentioning

112

Contrasting

Unclassified

Order By: Relevance

“…In a cochlea with no hair cells or peripheral processes, the site of action potential initiation is probably at the SGN cell body or central process. However, in group I animals, initial depolarization could have occurred at the hair cell and/or peripheral process instead of the SGN body (van den Honert and Stypulkowski 1984). We hypothesize that the site of excitation in response to both pulsatile and sinusoidal stimulation was at the hair cell and/or peripheral process in group I animals and at the SGN cell body or central process in group II animals.…”

Section: Fig 10mentioning

confidence: 85%

“…However, it is probable that surviving hair cells and related cochlear elements also directly affect electrical hearing. Cochlear implant function in hearing versus deaf ears has been studied in some detail at the neurophysiological level (Moxon 1971;van den Honert and Stypulkowski 1984;Shepherd and Javel 1997;Miller et al 2006), but we know less about the effects of preserved acoustic hearing on the responses to electrical stimulation at the psychophysical perceptual level. Thus, studies exploring the effects of preserving acoustic hearing on the perception of cochlear implant electrical stimulation are needed.…”

Section: Introductionmentioning

confidence: 99%

“…There are several possible mechanisms by which this might occur. Electrical stimulation can result in basilar membrane motion by several mechanisms, including electrically induced contraction of outer hair cells (OHCs), resulting in mechanical stimulation of inner hair cells (IHCs) and electrophonic hearing (Stevens and Jones 1939;Moxon 1971;van den Honert and Stypulkowski 1984;McAnally et al 1993;Nuttall and Ren 1995;Le Prell et al 2006;Miller et al 2006). It is also possible that the radial component of the electrical current results in direct excitation of the peripheral process and/or the IHC (van den Honert and Stypulkowski 1984).…”

Section: Introductionmentioning

confidence: 99%

“…Electrical stimulation can result in basilar membrane motion by several mechanisms, including electrically induced contraction of outer hair cells (OHCs), resulting in mechanical stimulation of inner hair cells (IHCs) and electrophonic hearing (Stevens and Jones 1939;Moxon 1971;van den Honert and Stypulkowski 1984;McAnally et al 1993;Nuttall and Ren 1995;Le Prell et al 2006;Miller et al 2006). It is also possible that the radial component of the electrical current results in direct excitation of the peripheral process and/or the IHC (van den Honert and Stypulkowski 1984). Furthermore, IHCs might generate spontaneous activity in the auditory nerve, which, by desynchronizing the population of auditory nerve fibers, may affect the across-fiber synchrony or the size of the neural population activated by the electrical stimulation (Wilson 1997;Haenggeli et al 1998;Hu et al 2003).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Effects of Hearing Preservation on Psychophysical Responses to Cochlear Implant Stimulation

Kang

Colesa

Swiderski

et al. 2009

JARO

View full text Add to dashboard Cite

Previous studies have shown that residual acoustic hearing supplements cochlear implant function to improve speech recognition in noise as well as perception of music. The current study had two primary objectives. First, we sought to determine how cochlear implantation and electrical stimulation over a time period of 14 to 21 months influence cochlear structures such as hair cells and spiral ganglion neurons. Second, we sought to investigate whether the structures that provide acoustic hearing also affect the perception of electrical stimulation. We compared psychophysical responses to cochlear implant stimulation in two groups of adult guinea pigs. Group I (11 animals) received a cochlear implant in a previously untreated ear, while group II (ten animals) received a cochlear implant in an ear that had been previously infused with neomycin to destroy hearing. Psychophysical thresholds were measured in response to pulse-train and sinusoidal stimuli. Histological analysis of all group I animals and a subset of group II animals was performed. Nine of the 11 group I animals showed survival of the organ of Corti and spiral ganglion neurons adjacent to the electrode array. All group I animals showed survival of these elements in regions apical to the electrode array. Group II animals that were examined histologically showed complete loss of the organ of Corti in regions adjacent and apical to the electrode array and severe spiral ganglion neuron loss, consistent with previous reports for neomycin-treated ears. Behaviorally, group II animals had significantly lower thresholds than group I animals in response to 100 Hz sinusoidal stimuli. However, group I animals had significantly lower thresholds than group II animals in response to pulse-train stimuli (0.02 ms/phase; 156 to 5,000 pps). Additionally, the two groups showed distinct threshold versus pulse rate functions. We hypothesize that the differences in detection thresholds between groups are caused by the electrical activation of the hair cells in group I animals and/or differences between groups in the condition of the spiral ganglion neurons.

show abstract

Section: Fig 10mentioning

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Effects of Hearing Preservation on Psychophysical Responses to Cochlear Implant Stimulation

Kang

Colesa

Swiderski

et al. 2009

JARO

View full text Add to dashboard Cite

show abstract

“…Saturation of firing rate could also be a limiting factor for synchronization to the envelope in electrical hearing, as a result of the limited dynamic range of neural firing (van den Honert and Stypulkowski 1984). In addition, the nonlinear signal processing performed by the speech processor may inadvertently introduce saturation-like effects with detrimental consequences on envelope ITD encoding.…”

Section: Effects Of Sound Intensitymentioning

confidence: 99%

Neural and Behavioral Sensitivity to Interaural Time Differences Using Amplitude Modulated Tones with Mismatched Carrier Frequencies

Blanks

Roberts

Buss

et al. 2007

JARO

View full text Add to dashboard Cite

Bilateral cochlear implantation is intended to provide the advantages of binaural hearing, including sound localization and better speech recognition in noise. In most modern implants, temporal information is carried by the envelope of pulsatile stimulation, and thresholds to interaural time differences (ITDs) are generally high compared to those obtained in normal hearing observers. One factor thought to influence ITD sensitivity is the overlap of neural populations stimulated on each side. The present study investigated the effects of acoustically stimulating bilaterally mismatched neural populations in two related paradigms: rabbit neural recordings and human psychophysical testing. The neural coding of interaural envelope timing information was measured in recordings from neurons in the inferior colliculus of the unanesthetized rabbit. Binaural beat stimuli with a 1-Hz difference in modulation frequency were presented at the best modulation frequency and intensity as the carrier frequencies at each ear were varied. Some neurons encoded envelope ITDs with carrier frequency mismatches as great as several octaves. The synchronization strength was typically nonmonotonically related to intensity. Psychophysical data showed that human listeners could also make use of binaural envelope cues for carrier mismatches of up to 2-3 octaves. Thus, the physiological and psychophysical data were broadly consistent, and suggest that bilateral cochlear implants should provide information sufficient to detect envelope ITDs even in the face of bilateral mismatch in the neural populations responding to stimulation. However, the strongly nonmonotonic synchronization to envelope ITDs suggests that the limited dynamic range with electrical stimulation may be an important consideration for ITD encoding.

show abstract

Laser stimulation of single auditory nerve fibers

et al. 2010

View full text Add to dashboard Cite

Objectives/Hypothesis One limitation with cochlear implants is the difficulty stimulating spatially discrete spiral ganglion cell groups because of electrode interactions. Multipolar electrodes have improved on this some, but also at the cost of much higher device power consumption. Recently, it has been shown that spatially selective stimulation of the auditory nerve is possible with a mid-infrared laser aimed at the spiral ganglion via the round window. However, these neurons must be driven at adequate rates for optical radiation to be useful in cochlear implants. We herein use single-fiber recordings to characterize the responses of auditory neurons to optical radiation. Study Design In vivo study using normal-hearing adult gerbils. Methods Two diode lasers were used for stimulation of the auditory nerve. They operated between 1.844 μm and 1.873 μm, with pulse durations of 35 μs to 1,000 μs, and at repetition rates up to 1,000 pulses per second (pps). The laser outputs were coupled to a 200-μm-diameter optical fiber placed against the round window membrane and oriented toward the spiral ganglion. The auditory nerve was exposed through a craniotomy, and recordings were taken from single fibers during acoustic and laser stimulation. Results Action potentials occurred 2.5 ms to 4.0 ms after the laser pulse. The latency jitter was up to 3 ms. Maximum rates of discharge averaged 97 ± 52.5 action potentials per second. The neurons did not strictly respond to the laser at stimulation rates over 100 pps. Conclusions Auditory neurons can be stimulated by a laser beam passing through the round window membrane and driven at rates sufficient for useful auditory information. Optical stimulation and electrical stimulation have different characteristics; which could be selectively exploited in future cochlear implants. Level of Evidence Not applicable.

show abstract

Physiological properties of the electrically stimulated auditory nerve. II. Single fiber recordings

Cited by 234 publications

References 17 publications

Effects of Hearing Preservation on Psychophysical Responses to Cochlear Implant Stimulation

Effects of Hearing Preservation on Psychophysical Responses to Cochlear Implant Stimulation

Neural and Behavioral Sensitivity to Interaural Time Differences Using Amplitude Modulated Tones with Mismatched Carrier Frequencies

Laser stimulation of single auditory nerve fibers

Contact Info

Product

Resources

About