Pupil response to familiar and unfamiliar talkers in the recognition of noise-vocoded speech

Abstract

In some challenging listening conditions, listeners are more accurate at recognizing speech produced by a familiar talker compared to unfamiliar talkers. However, previous studies have found little to no talker-familiarity benefit in the recognition of noise-vocoded speech, potentially due to limitations in the talker-specific details conveyed in noise-vocoded signals. Although no strong effect on performance has been observed, listening to a familiar talker may reduce the listening effort experienced. The current study used pupillometry to assess how talker familiarity could impact the amount of effort required to recognize noise-vocoded speech. Four groups of normal-hearing, listeners completed talker familiarity training, each with a different talker. Then, listeners repeated sentences produced by the familiar (training) talker and three unfamiliar talkers. Sentences were mixed with multi-talker babble, and were processed with an 8-channel noise-vocoder; SNR was set to a participant’s 50% correct performance level. Preliminary results demonstrate no overall talker-familiarity benefit across training groups. Examining each training group separately showed differences in pupil response for familiar and unfamiliar talkers, but the direction and size of the effect depended on the training talker. These preliminary findings suggest that normal-hearing, listeners make use of limited talker-specific details in the recognition of noise-vocoded speech.