Spetner N B, Olsho L W
Child Development and Mental Retardation Center, University of Washington, Seattle 98195.
Child Dev. 1990 Jun;61(3):632-52.
Frequency resolution is a fundamental capacity of the auditory system that underlies the perception of all complex sounds. The development of this capacity has not been well characterized in humans. This investigation used a nonsimultaneous pulsation threshold technique to examine the development of infant frequency resolution. Psychophysical tuning curves were obtained for 3- and 6-month-olds and for adults at either 500, 1,000, or 4,000 Hz. Both the sensation level and the sound pressure level of the stimulus were varied for adults to determine the contribution of stimulus intensity to age differences in frequency resolution. At 500 and 1,000 Hz, 3- and 6-month-olds' tuning curve widths were equivalent to adults'. At 4,000 Hz, the 3-month-olds' tuning curves were broader than those of 6-month-olds and adults, even when absolute sound pressure level was equivalent. The maturation of psychophysical frequency resolution in infants is discussed in terms of the general development of the auditory system and of nonsensory factors that might contribute to age differences in performance.
频率分辨是听觉系统的一项基本能力，是所有复杂声音感知的基础。这种能力在人类中的发展尚未得到充分描述。本研究采用非同时搏动阈值技术来检测婴儿频率分辨能力的发展。获得了3个月大、6个月大婴儿以及成人在500、1000或4000赫兹频率下的心理物理学调谐曲线。针对成人，改变了刺激的感觉水平和声压水平，以确定刺激强度对频率分辨年龄差异的影响。在500和1000赫兹时，3个月大及6个月大婴儿的调谐曲线宽度与成人相当。在4000赫兹时，即使绝对声压水平相同，3个月大婴儿的调谐曲线也比6个月大婴儿和成人的更宽。从听觉系统的总体发育以及可能导致表现年龄差异的非感觉因素方面，对婴儿心理物理学频率分辨能力的成熟进行了讨论。
