Production of Syntactic Stress in Alaryngeal Speech

An acoustical investigation of syntactic stress in alaryngeal speech was undertaken. Measurements were made of fundamental frequency, relative intensity, vowel duration, and intersyllable duration from noun compounds and noun phrases spoken by four normal speakers, four esophageal speakers, four Blom-Singer tracheoesophageal speakers, four users of the Western Electric 5A electrolarynx, and one user of the Servox electrolarynx. Results indicated that esophageal and tracheoesophageal speakers were able to manipulate the relative magnitudes of fundamental frequency, intensity, and vowel duration in a manner comparable to those of normal speakers. With the exception of one user of the Western Electric 5A electrolarynx, who manipulated both fundamental frequency and duration, electrolarynx users generally manipulated only duration properties. All alaryngeal speakers manipulated intersyllable duration, whereas normal speakers did not. The degree of acoustical contrast for both peak fundamental frequency and vowel duration was significantly greater on syllables in final position than in initial position for normal and alaryngeal speakers alike. These findings suggest that stress contrasts in alaryngeal speech are based on a complex of acoustic cues which are influenced by linguistic structure.