Discrimination of stochastic frequency modulation as a predictor of electro-acoustic stimulation benefit.

The amount of benefit in speech intelligibility in noise can vary widely for cochlear‐implant (CI) users when low‐frequency acoustic stimulation is combined with electric stimulation. This variability may, in part, be explained by the listener’s ability to follow fundamental frequency (f0) changes with electric stimulation only: those who benefit the least may be most adept at processing f0 in the electric region. The present study measured the ability of CI users to discriminate stochastic FM patterns when presented acoustically or electrically only. The stimuli were 200‐Hz carriers randomly modulated in frequency by 5‐Hz lowpass noise. A cued 2IFC procedure was used. In one of the two observation intervals, the cue pattern was repeated; in the other, the modulator was inverted so that the pattern of instantaneous frequency fluctuation mirrored that of the cue pattern at the center frequency. Discrimination thresholds were measured in terms of the FM depth needed to discriminate the deviant from the cue ...