Reinhardt-Rutland A H
University of Ulster at Jordanstown, Newtownabbey, Northern Ireland.
J Gen Psychol. 1998 Jul;125(3):229-44. doi: 10.1080/00221309809595547.
The reduced sensitivity that accompanies some auditory aftereffects has been linked to sensory fatigue. However, changing-loudness aftereffects are unaffected by reduced sensitivity, according to previous evidence from a single-interval forced-choice procedure. That result was confirmed in the present study, in which an adjustment procedure was used to measure changing-loudness aftereffects. In each condition, the listener set the rate of intensity change in test stimuli until they were heard as steady in loudness. The mean of 10 such settings was taken as a measure of the aftereffect's magnitude. The standard deviation of the 10 settings indicated the listener's sensitivity in perceiving changing intensity: The greater the standard deviation, the less the sensitivity. Consistent with previous data, the magnitude of increasing-loudness aftereffects (Experiment 1) and decreasing-loudness aftereffects (Experiment 2) varied according to the adaptation condition, but sensitivity did not. Although sensory fatigue may contribute to aftereffects, the author concluded that reduced sensitivity is not a reflection of sensory fatigue. Instead, it may be explained as a methodological artifact dependent on whether the adapted property is processed by direct or indirect mechanisms. Aftereffects only concern direct mechanisms, but the test stimuli used in their measurement may entail both types of mechanisms: If the measurement entails both types of mechanisms, sensitivity is reduced; if not, sensitivity is unaltered.
一些听觉后效伴随的敏感性降低与感觉疲劳有关。然而，根据单间隔强迫选择程序的先前证据，响度变化后效不受敏感性降低的影响。本研究证实了这一结果，其中使用了一种调整程序来测量响度变化后效。在每种情况下，听者设定测试刺激的强度变化率，直到他们感觉响度稳定。这10次设定的平均值被用作后效大小的度量。这10次设定的标准差表明听者在感知强度变化方面的敏感性：标准差越大，敏感性越低。与先前的数据一致，响度增加后效（实验1）和响度降低后效（实验2）的大小根据适应条件而变化，但敏感性没有。虽然感觉疲劳可能导致后效，但作者得出结论，敏感性降低并非感觉疲劳的反映。相反，它可以解释为一种方法学假象，取决于适应特性是通过直接机制还是间接机制处理。后效仅涉及直接机制，但测量中使用的测试刺激可能涉及两种机制：如果测量涉及两种机制，敏感性就会降低；如果不涉及，敏感性则不变。
