Sharf D J, Benson P J
J Acoust Soc Am. 1982 Apr;71(4):1008-15. doi: 10.1121/1.387652.
A continuing problem in speech research is the comparison of phonetically similar but acoustically distinct sounds such as the comparison between adult speech and child speech. This problem is especially important in the remediation of speech disorders. In this study, we focus on this problem as manifested in the disordered production of [r] sounds. Stimuli which varied in F2 and F3 onset frequencies were synthesized to span continua from [r] to [w] for adult, child, and scaled adult (formants 1.5 times adult values) speakers. These stimuli were presented to 18 naive adults for identification as "R"or "W" at three listening sessions to test for stability of category boundaries. Significant shifts in category boundaries were found for all three continua between sessions one and two but not between sessions two and three. Category boundaries in terms of formant frequencies showed significant differences between the adult and childlike continua. Rescaling these values on a psychophysical dimension and adjusting for formant spread brought the category boundaries into close alignment. In free choice testing, synthesized [r] and [w] stimuli were identified by most subjects at least as well as natural [r] and [w] stimuli but synthesized child [r] stimuli were identified by most subject considerably better than natural child [r] stimuli.
语音研究中一个持续存在的问题是对语音上相似但声学上不同的声音进行比较，比如成人语音和儿童语音之间的比较。这个问题在言语障碍的矫治中尤为重要。在本研究中，我们关注这个问题在[r]音发音紊乱中的表现。合成了F2和F3起始频率不同的刺激音，以涵盖从成人、儿童以及缩放成人（共振峰为成人值的1.5倍）发音者的[r]到[w]的连续体。这些刺激音在三次听力测试中呈现给18名未受训练的成年人，让他们辨别是“R”还是“W”，以测试类别边界的稳定性。在第一和第二次测试之间，所有三个连续体的类别边界都有显著变化，但在第二和第三次测试之间没有。就共振峰频率而言，成人和类似儿童的连续体之间的类别边界存在显著差异。在心理物理学维度上重新调整这些值并考虑共振峰扩展后，类别边界趋于一致。在自由选择测试中，大多数受试者对合成的[r]和[w]刺激音的辨别能力至少与自然的[r]和[w]刺激音相当，但大多数受试者对合成的儿童[r]刺激音的辨别能力明显优于自然的儿童[r]刺激音。
