Turn an Ear to Hear: How Hearing-Impaired Listeners Can Exploit Head Orientation to Enhance Their Speech Intelligibility in Noisy Social Settings.

Turning an ear toward the talker can enhance spatial release from masking. Here, with their head free, listeners attended to speech at a gradually diminishing signal-to-noise ratio and with the noise source azimuthally separated from the speech source by 180° or 90°. Young normal-hearing adult listeners spontaneously turned an ear toward the speech source in 64% of audio-only trials, but a visible talker's face or cochlear implant (CI) use significantly reduced this head-turn behavior.

Cochlear implant simulator with independent representation of the full spiral ganglion.

In cochlear implant simulation with vocoders, narrow-band carriers deliver the envelopes from each analysis band to the cochlear positions of the simulated electrodes. However, this approach does not faithfully represent the continuous nature of the spiral ganglion. The proposed "SPIRAL" vocoder simulates current spread by mixing all envelopes across many tonal carriers.

Head orientation benefit to speech intelligibility in noise for cochlear implant users and in realistic listening conditions.

Cochlear implant (CI) users suffer from elevated speech-reception thresholds and may rely on lip reading. Traditional measures of spatial release from masking quantify speech-reception-threshold improvement with azimuthal separation of target speaker and interferers and with the listener facing the target speaker. Substantial benefits of orienting the head away from the target speaker were predicted by a model of spatial release from masking.

The benefit of head orientation to speech intelligibility in noise.

Spatial release from masking is traditionally measured with speech in front. The effect of head-orientation with respect to the speech direction has rarely been studied. Speech-reception thresholds (SRTs) were measured for eight head orientations and four spatial configurations.

The benefit of bilateral versus unilateral cochlear implantation to speech intelligibility in noise.

Objectives: To develop a predictive model of spatial release from masking (SRM) for cochlear implantees, and validate this model against data from the literature. To establish the spatial configurations for which the model predicts a large advantage of bilateral over unilateral implantation. To collect data to support these predictions and generate predictions of more typical advantages of bilateral implantation.