Simulating the effects of spread of electric excitation on musical tuning and melody identification with a cochlear implant.

Purpose: To determine why, in a pilot study, only 1 of 11 cochlear implant listeners was able to reliably identify a frequency-to-electrode map where the intervals of a familiar melody were played on the correct musical scale. The authors sought to validate their method and to assess the effect of pitch strength on musical scale recognition in normal-hearing listeners.

Method: Musical notes were generated as either sine waves or spectrally shaped noise bands, with a center frequency equal to that of a desired note and symmetrical (log-scale) reduction in amplitude away from the center frequency.