Vowel intelligibility in clear speech produced by electrolaryngeal speakers

This study assessed vowel intelligibility when electrolaryngeal (EL) speakers were instructed to use clear speech (CS). Eighteen consonant-vowel-consonant words containing /i/, /ɪ/, /ɛ/, and /ae/ were spoken by 10 laryngectomees in habitual speech (HS) and CS conditions. A total of 4,320 words across both speech conditions were recorded and then transcribed by 12, naive listeners. Results indicate that vowel intelligibility was 85.4% (range = 77.8% to 90.6%) when EL speakers used HS compared to 82.7% (range = 75.0% to 92.8%) in CS. This finding suggests that CS does not facilitate improved vowel intelligibility for EL speakers. Future research will seek explanations for the lack of a CS benefit by examining the acoustic changes that occur when EL speakers use CS.