Werner Lynne A, Parrish Heather K, Holmer Nicole M
Department of Speech and Hearing Sciences, University of Washington, Seattle, Washington 98105-6246, USA.
J Acoust Soc Am. 2009 Feb;125(2):1040-49. doi: 10.1121/1.3050254.
Adults are more sensitive to a sound if they know when the sound will occur. In the present experiment, the effects of temporal uncertainty and temporal expectancy on infants' and adults' detection of a 1 kHz tone in a broadband noise were examined. In one experiment, masked sensitivity was measured with an acoustic cue and without an acoustic cue to possible tone presentation times. Adults' sensitivity was greater for the cue than for the no-cue condition, while infants' sensitivity did not differ significantly between the cue and no-cue conditions. In a second experiment, the effect of temporal expectancy was investigated. The detection advantage for sounds occurring at an expected (most frequent) time, over sounds occurring at unexpected (less frequent) times, was examined. Both infants and adults detected a tone better when it occurred before or at an expected time following a cue than when it occurred at a later time. Thus, despite the fact that the auditory cue did not improve infants' sensitivity, it nonetheless provided the basis for temporal expectancies. Infants, like adults, are more sensitive to sounds that are consistent with temporal expectancy.
如果成年人知道声音何时会出现，他们对声音会更敏感。在本实验中，研究了时间不确定性和时间预期对婴儿和成年人在宽带噪声中检测1千赫纯音的影响。在一个实验中，通过声学提示以及不通过声学提示（提示可能的纯音呈现时间）来测量掩蔽敏感度。对于提示条件，成年人的敏感度高于无提示条件，而婴儿在提示和无提示条件下的敏感度没有显著差异。在第二个实验中，研究了时间预期的影响。考察了在预期（最频繁）时间出现的声音相对于在意外（较不频繁）时间出现的声音的检测优势。当纯音在提示后的预期时间之前或之时出现时，婴儿和成年人对其的检测都比在更晚时间出现时更好。因此，尽管听觉提示并没有提高婴儿的敏感度，但它仍然为时间预期提供了基础。与成年人一样，婴儿对与时间预期一致的声音更敏感。
