Cortical Speech Processing in Postlingually Deaf Adult Cochlear Implant Users, as Revealed by Functional Near-Infrared Spectroscopy.

Only 15 implant users and 14 normal-hearing listeners had usable data, so the sample is small and the correlations may not be stable. Four implant users and five normal-hearing listeners were excluded because hair prevented good optode contact, and one implant user withdrew, which may have changed the group that was analysed. The implant group was older than the normal-hearing group, and the authors considered this age difference when selecting regions of interest. fNIRS channels over the implant coil could not be measured, and the exact brain location of each channel is uncertain. The study compared existing implant users with normal-hearing listeners at one time point, so it shows associations, not causes or treatment effects. Many brain regions were tested, and some results did not survive correction for multiple comparisons. All analysed implant users had a right-ear implant and at least 12 months of experience, so findings may not apply to left-ear implants or newly implanted users.

Funding is listed as veski, a University PhD scholarship, the Australian Fulbright Commission, and an Australian Research Council Grant. The supplied text does not report commercial funding or additional author conflicts.

Do not conclude that fNIRS brain activation can be used to assess cochlear implant candidates or that these patterns cause poor speech understanding. The study analysed existing groups and found correlations, not treatment effects.