No Benefit of Deriving Cochlear-Implant Maps From Binaural Temporal-Envelope Sensitivity for Speech Perception or Spatial Hearing Under Single-Sided Deafness.

Nine listeners is a small sample, and only five completed all sessions. Several participants missed sessions because they discontinued or because of COVID-19 restrictions. The listeners were not randomly assigned to map types; each person was tested with the clinical map first, then the experimental map, then the clinical map again. The sample was not representative of all cochlear implant users: eight used MED-EL devices, one used a Cochlear device, and none used Advanced Bionics. Six of nine listeners had long MED-EL arrays, which may have left little frequency mismatch to correct. Scores improved across repeated speech sessions, so a map benefit could not be separated cleanly from practice. For many listeners the clinical and experimental maps were similar, and the largest changes removed information below 1000 Hz, which the acoustic ear can still hear.

The authors declared no conflicts of interest.

Do not conclude that timing-based cochlear implant maps should be offered routinely. The study found no clear improvement in localization or speech-in-noise after six months, and S4 discontinued after four months because the experimental map sounded unsatisfactory.