JAAA CEU Program

Questions refer to Zaleski-King et al, “Bimodal Cochlear Implant Listeners’ Ability to Perceive Minimal Audible Angle Differences,” 659–671.

Learner Outcomes:

Readers of this article should be able to:

• Summarize the literature describing bimodal access to interaural level and interaural timing difference cues.

• Discuss the limitations adversely affecting bimodal binaural integration.

CEU Questions:

1. The literature has shown that some bimodal listeners can take advantage of interaural cues when speech sources are spatially separated, based on:

   • the head shadow effect

   • binaural summation

   • interaural time difference (ITD) integration

2. Many of the documented binaural benefits of bimodal stimulation have been demonstrated in:

   • environments providing opportunities for “dip listening” during fluctuations in noise

   • optimized, directly controlled laboratory conditions

   • in comparison to patients with bilateral hearing aids

3. As high-frequency content increases, interaural level differences (ILDs) are:

   • more salient

   • less salient

   • unchanged

4. Hearing aid processing produces a(n) _______ timing delay in comparison to cochlear implant (CI) processors, resulting in ________.

   • smaller, difficulty for computation of neural cues

   • larger, difficulty for computation of neural cues

   • equivalent, optimized binaural computation

5. A broadband stimulus was used in the study to:

   • optimize ILD cues

   • improve access to overall loudness cues

   • provide an opportunity for acoustic and electric stimulation overlap

6. The interdevice delay (IDD) was used in this study to represent:

   • the difference in delay required for lateralization of the broadband stimulus

   • the delay between the hearing aid (HA) and CI processors required for the listener to achieve a percept of a centered, single stimulus

   • the loudness difference required for equal between-ear intensity percept

7. The results of this study generally showed that:

   • providing ITD access to bimodal listeners can be achieved through determining the IDD

   • providing localization information to bimodal listeners necessitates more substantial changes to device speech-processing algorithms and fitting procedures

   • providing access to ILDs requires monaural listening for bimodal patients

8. The authors hypothesized the Listener B6 demonstrated greater difficulty establishing differences in loudness cues because:

   • this listener could not identify ITDs

   • this listener had the most pronounced low-frequency hearing loss in the hearing aid ear

   • this listener had the least experience listening bimodally

9. One limitation identified by the authors that might have contributed to the variability in interaural loudness perception:

   • differences in compression ratios

   • differences in age of participants

   • differences in hearing aid manufacturer/model

10. In conclusion, the high variability and the general difficulty demonstrated in tasks requiring binaural comparisons supports the idea that:

    • CIs best preserve ILD cues used for the head shadow effect

    • listeners likely extracted monaural loudness cues to complete the task

    • listening experience determines the ability to compute binaural cues