Temporal pitch in electric hearing

Zeng, Fan‐Gang

doi:10.1016/s0378-5955(02)00644-5

Cited by 283 publications

(258 citation statements)

References 38 publications

Supporting

Mentioning

242

Contrasting

Unclassified

Order By: Relevance

“…These variations may be perceived as different pitches so long as the modulation frequencies do not exceed the "pitch saturation limit" for implant patients, i.e., the rate or frequency (or modulation frequency) at which further increases in rate or frequency do not produce further increases in pitch. This limit is about 300 Hz for most patients (e.g., Zeng, 2002), although it can range as high as 1 kHz or a bit beyond that for exceptional patients (e.g., Hochmair-Desoyer et al, 1983;Townshend et al, 1987;Zeng, 2002). The cutoff frequency for the envelope detectors in the envelope-based strategies typically is between 200 and 400 Hz, which corresponds to the pitch saturation limit for most patients.…”

Section: Possible Deficit In the Representation Of Fine Structure Infmentioning

confidence: 99%

“…As has been mentioned, temporal representations of frequencies with electrically elicited hearing are limited to frequencies lower than the pitch saturation limit, which is around 300 Hz for most patients. In addition, the difference limens (DLs) for rates or frequencies of electric stimuli are much worse (typically ten times worse) than the DLs for normal hearing and acoustic stimuli, in this low-frequency range below 300 Hz (e.g., Zeng, 2002;Baumann and Nobbe, 2004).…”

Section: Less-than-resolute Representations Of Fundamental Frequenciementioning

confidence: 99%

See 1 more Smart Citation

Cochlear implants: A remarkable past and a brilliant future

2008

View full text Add to dashboard Cite

The aims of this paper are to (i) provide a brief history of cochlear implants; (ii) present a status report on the current state of implant engineering and the levels of speech understanding enabled by that engineering; (iii) describe limitations of current signal processing strategies and (iv) suggest new directions for research. With current technology the "average" implant patient, when listening to predictable conversations in quiet, is able to communicate with relative ease. However, in an environment typical of a workplace the average patient has a great deal of difficulty. Patients who are "above average" in terms of speech understanding, can achieve 100% correct scores on the most difficult tests of speech understanding in quiet but also have significant difficulty when signals are presented in noise. The major factors in these outcomes appear to be (i) a loss of low-frequency, fine structure information possibly due to the envelope extraction algorithms common to cochlear implant signal processing; (ii) a limitation in the number of effective channels of stimulation due to overlap in electric fields from electrodes, and (iii) central processing deficits, especially for patients with poor speech understanding. Two recent developments, bilateral implants and combined electric and acoustic stimulation, have promise to remediate some of the difficulties experienced by patients in noise and to reinstate low-frequency fine structure information. If other possibilities are realized, e.g., electrodes that emit drugs to inhibit cell death following trauma and to induce the growth of neurites toward electrodes, then the future is very bright indeed.

show abstract

Section: Possible Deficit In the Representation Of Fine Structure Infmentioning

confidence: 99%

Section: Less-than-resolute Representations Of Fundamental Frequenciementioning

confidence: 99%

Cochlear implants: A remarkable past and a brilliant future

2008

View full text Add to dashboard Cite

show abstract

“…Multiple studies indicate that recipients are only able to utilise these cues to discriminate pitch for rates up to around 300 Hz [48,49], implying that many CI users would have difficulty using these temporal pitch cues for stimuli with a fundamental frequency (F0) above middle-C (261.63 Hz) [9]. The salience of temporal pitch cues is also affected by a range of factors including: sufficient modulation depth [48,49,50] ; alignment of the phase of the pulse train across the electrode array [51]; and a high sampling rate [48,49].…”

Section: Pitch Perceptionmentioning

confidence: 99%

A comparison of the speech recognition and pitch ranking abilities of children using a unilateral cochlear implant, bimodal stimulation or bilateral hearing aids

Looi

Radford

2011

International Journal of Pediatric Otorhinolaryngology

View full text Add to dashboard Cite

ObjectiveThe present study compared the speech recognition and pitch ranking abilities of normally-hearing children (n = 15) to children using a cochlear implant (CI) alone (n = 8), bilateral hearing aids (HAs) (n = 6), or bimodal stimulation (BMS) (n = 9). It was hypothesised that users of BMS would score higher on tasks of speech and pitch perception than children using a CI alone, but not children using HAs. MethodsParticipants were assessed on tasks of monosyllabic word recognition in quiet, sentence recognition in quiet and noise (10dB signal-to-noise ratio), and a pitch ranking task using pairs of sung vowels one, half, and a quarter of an octave apart. ResultsThere were no significant differences between the mean percentage-correct scores of the four participant groups for either words in quiet or sentences in quiet and noise. However, the proportion of bimodal users who scored > 80% correct (80%) was significantly greater than the proportion of highscoring unilateral CI (25%) or bilateral HA users (17%). Contrary to expectations, there was also no significant difference between the pitch ranking scores of users of BMS and users of a CI alone for all three interval sizes (p < 0.05, RM-ANOVA). However participants using only acoustic hearing (i.e. the NH and HA groups) scored significantly higher than participants using electrical stimulation (i.e. the CI and BMS groups) on the pitch ranking task (p < 0.05; RM-ANOVA). ConclusionsContrary to findings in postlingually deafened adults, we found no significant bimodal advantage for pitch perception in prelingually deafened children. However, the performance of children using electrical stimulation was significantly poorer than children using only acoustic stimulation. Further research is required to investigate the contribution of the non-implanted ears of users of BMS to pitch perception, and the effect of hearing loss on the development of pitch perception in children.

show abstract

“…Any loss of monaural synchronization would be even more important for binaural processing because the process of coincidence detection produces binaural synchronization that is approximately the square of the monaural synchronies Batra and Yin 2004). Implant listeners tend to have acute sensitivity to the presence of amplitude modulation (Shannon 1992), but there is some evidence that the ability to detect small changes in stimulus rate is relatively poor (Zeng 2002). Furthermore, in at least one case, better ITD discrimination was found for an electrode pair that was mismatched in place/pitch than for the matched pair (Long et al 2003).…”

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

Temporal pitch in electric hearing

Cited by 283 publications

References 38 publications

Cochlear implants: A remarkable past and a brilliant future

Cochlear implants: A remarkable past and a brilliant future

A comparison of the speech recognition and pitch ranking abilities of children using a unilateral cochlear implant, bimodal stimulation or bilateral hearing aids

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

Contact Info

Product

Resources

About