Spatial Release From Masking in 2-Year-Olds With Normal Hearing and With Bilateral Cochlear Implants.

The sample was small: 13 children in each group, and only 9 of the 13 children with bilateral cochlear implants provided thresholds in all three listening conditions. 4 of the 13 children with bilateral cochlear implants could not complete the competitor conditions, and 1 child could not be tested in any condition, so the results may not represent all toddlers with implants. The implant group had a younger hearing age than the normal-hearing group, and when hearing age was controlled, group differences in thresholds were no longer significant. The study did not test unilateral listening, so it cannot separate the effect of using two implants from the effect of the child's usual bilateral listening experience. Competitors were always placed toward the right side or the first-implanted ear, so asymmetries between ears were not examined. Because the children used unsynchronized clinical processors, the study cannot show that binaural hearing caused the spatial-release result. The task tested known single words after familiarization, not vocabulary learning or more complex speech, so it may not capture everyday speech-in-noise demands.

The supplied text reports funding from the National Institute on Deafness and Other Communication Disorders. It does not report other conflicts of interest.

Do not conclude that bilateral cochlear implants make toddlers hear in noise like normal-hearing toddlers. The spatial-release result was not significantly different between groups, but the implant group had higher speech reception thresholds, and the study did not test unilateral listening or synchronized binaural processing.