The use of the Lombard Effect in Improving Alaryngeal Speech

The present study examined and compared the Lombard effect among laryngeal and alaryngeal speakers including esophageal, tracheoesophageal, pneumatic artificial laryngeal, electrolaryngeal speakers of Cantonese. The subsequent change in intelligibility was also examined.

A total of 52 native Cantonese-speaking laryngeal and alaryngeal speakers (10 laryngeal , 8 laryngeal , 13 electrolaryngeal , 11 esophageal, and 10 tracheoesophageal) participated in a reading task involving three 10-syllable Cantonese sentences under 10 background conditions: quiet, 60 dB, 65 dB, 70 dB, 75 dB, 80 dB, 85 dB, 90 dB, 95 dB, and 100 dB white background noise. Speech intelligibility associated with speaking conditions were evaluated by five naïve Cantonese speakers.

Output intensity was significantly increased in all speaker types under all nine noisy background conditions when compared with the quiet condition. However, the amount of increase was different for different modes of phonation. In addition, significant difference in speech intelligibility between laryngeal and alaryngeal speakers was found at all conditions, but not among any alaryngeal speech.

The Lombard reflex is still present after total laryngectomy. Yet, different alaryngeal speech was associated with different amount of loudness change, and subsequent improvement in intelligibility was not observed.