Studies on speech perception by primates

使用反应时间任务，日本猕猴，黑猩猩和人类的听觉灵敏度，“响度”和语音感知进行了研究。使用纯音（62.5 - 32 k Hz，-10-90 dB SPL）测量听觉灵敏度和“响度”。基于反应时数据，得到等响等值线。人类表现出U形曲线，对500-4k Hz的音调最敏感。黑猩猩表现出W形曲线，与旧大陆和新大陆的猴子相似。黑猩猩对1 k和8 k Hz的音调敏感。而在2k-4k Hz时，听觉灵敏度降低。使用自然和合成的日语和法语元音。当元音对的成员彼此相似时，预期反应时间会更长。反应时数据用MDSCAL和聚类分析进行分析。黑猩猩和人类的主要区别在于， ...更多信息 黑猩猩的rom /o/更长。因此，有人建议，黑猩猩需要更长的反应时间的基础上的第二共振峰的频率差异的元音的歧视。W形黑猩猩的听觉敏感功能可以部分解释人类和黑猩猩之间的种间差异。合成的塞音具有不同的值的声音开始时间和第二和第三共振峰的瞬态频率也被用来研究的分类感知的清音（/ga/-/ka/）和发音的地方（/ba/-/da/）的功能。获得了以下结果。虽然区分浊塞音和清塞音很容易，但对黑猩猩来说，根据发音的位置来区分塞音是很困难的。黑猩猩对塞音的发音和位置特征有明显的区分能力。每一个结界的位置，都与人类的结界位置相差不大。少

Using a reaction time task, auditory sensitivity, 'loudness' and perception of speech sounds by Japanese macaques, chimpanzees and humans were studied. Auditory sensitivity and 'loudness' were measured using pure tones (62.5 - 32k Hz, -10 - 90 dB SPL). Based on reaction time data, equal loudness contours were obtained. Humans showed U-shaped curves and were most sensitive to 500-4k Hz tones. Chimpanzees showed W-shaped curves, which were similar to those of Old- and New-world monkeys. Chimanzees were sensitive to 1k and 8k Hz tones. However, a decrease in auditory sensitivity was observed at 2k-4k Hz.Then the discrimination of vowels was investigated. Natural and synthesized Japanese and French vowels were used. Longer reaction times were expected when members of a vowel pair were similar to each other. Reaction time data were analyzed by MDSCAL and cluster analyses. The main difference between chimpanzees and humans was that the reaction times for discriminating /i/ from /u/ and /e/ f … More rom /o/ were longer for chimpanzees. Thus, it is suggested that chimpanzees require longer reaction times for discrimination of vowels based on differenses in the frequency of the second formant. The species difference between humans and chimpanzees may be partially explained by the W-shaped chimpanzees' auditory sensitivity functions.Perception of consonant(mainly stops)+vowel(/a/) syllables was studied. Synthesized stop consonants with different values of voice onset time and 2nd and 3rd formant transient frequencies were also used for studying categorical perception of voicing (/ga/-/ka/) and place of articulation (/ba/-/da/) features. Following results were obtained. Although discrimination between voiced and unvoiced stops was easy, discrimination of stops based on the place of articulation was difficult for chimpanzees. Chimpanzees showed categorical discrimination of voicing and place features of stop consonants. The position of each boundary was not so different from that of humans. Less