Comparison of Unilateral CI vs. Bimodal Stimulation in Prosodic Perception

People with severe to profound hearing loss often do not get satisfactory benefit from their hearing aids. A cochlear implant (CI) is a prosthetic device for the inner ear which can directly stimulate the auditory nerve, bypassing damaged inner ear hair cells and thus provide audible sensations to profoundly deaf patients.

Currently, one CI is funded by NHS England for adult patients and the eligibility criteria for implantation has been relaxed in recent years. As a result, there are now an increasing number of unilateral CI users who possess low-frequency residual hearing in their non-implanted ear. For many patients this residual hearing may still be usefully amplified by a HA. This configuration, consisting of a CI and a contralateral HA, is known as bimodal stimulation.

The PEPS-C receptive test battery has been previously used to assess prosody perception in hearing loss.

The current project will use selected tests from the PEPS-C prosodic test battery to assess intonation, emotion and phrase stress perception ability in adults with bimodal stimulation using both devices together and CI alone.

Inclusion criteria

• Adult
• Has unilateral Cochlear Implant
• Consistent use of Hearing Aid
• Obtains some benefit in speech discrimination from hearing aid (> 20% AB words)
• Post-lingually deafened
• Fluent English

Exclusion criteria

• Longstanding significant asymmetry (> 20 dB HL 4 frequency average) in hearing where the unimplanted ear is the worse ear
• Inconsistent Hearing Aid use
• Significant conductive hearing loss (> 20 dB HL 4 frequency average)
• Using Electro-Acoustic stimulation Cochlear Implant
• Aetiology of hearing loss likely associated with auditory neuropathy
• Significantly abnormal appearance of cochlea or cochlear nerve