BiModal Hearing Review
Sammeth, Bundy, and Miller reviewed the recent voluminous literature regarding bimodal hearing (one cochlear implant and one hearing aid) and bilateral cochlear implants (CIs) in children and adults. Bilateral listening (via bimodal hearing or bilateral CIs) provides reduction of the head shadow effect, provides binaural summation and allows binaural squelch. Additionally, binaural listening allows one to localize (i.e., to identify the origin of sound) based on interaural timing and interaural loudness cues. Sammeth, Bundy, and Miller note that when only one auditory pathway is treated (i.e., aided) in cases with significant hearing loss in both ears, the unaided ear can be expected to experience significant auditory deprivation effects over time.
In summary, there exists compelling evidence to support bilateral CIs and bimodal hearing with specific regard to speech recognition in quiet and in noise, and with regard to lateralization and localization issues, and in perceived benefit and satisfaction.
For More Information, References, and Recommendations
Sammeth CA, Bundy AM, Miller DA. (2011) Bimodal Hearing or Bilateral Cochlear Implants – A Review of The Research Literature Seminars in Hearing 32(1):3-31.