Faculty of Psychology and Neuroscience, Maastricht University, Universiteitssingel 40, Maastricht, The Netherlands.
Hear Res. 2011 Jul;277(1-2):152-62. doi: 10.1016/j.heares.2011.01.013. Epub 2011 Jan 27.
An interrupted sound can be perceived as continuous when noise masks the interruption, creating an illusion of continuity. Recent findings have shown that adaptor sounds preceding an ambiguous target sound can influence listeners' rating of target continuity. However, it remains unclear whether these aftereffects on perceived continuity influence sensory processes, decisional processes (i.e., criterion shifts), or both. The present study addressed this question. Results show that the target sound was more likely to be rated as 'continuous' when preceded by adaptors that were perceived as clearly discontinuous than when it was preceded by adaptors that were heard (illusorily or veridically) as continuous. Detection-theory analyses indicated that these contrastive aftereffects reflect a combination of sensory and decisional processes. The contrastive sensory aftereffect persisted even when adaptors and targets were presented to opposite ears, suggesting a neural origin in structures that receive binaural inputs. Finally, physically identical but perceptually ambiguous adaptors that were rated as 'continuous' induced more reports of target continuity than adaptors that were rated as 'discontinuous'. This assimilative aftereffect was purely decisional. These findings confirm that judgments of auditory continuity can be influenced by preceding events, and reveal that these aftereffects have both sensory and decisional components.
当噪声掩盖中断时，间断的声音可以被感知为连续的，从而产生连续的错觉。最近的研究结果表明，在模棱两可的目标声音之前出现的适配声音会影响听众对目标连续性的评价。然而，这些对感知连续性的后效是否会影响感觉过程、决策过程（即标准转移），或者两者兼而有之，目前还不清楚。本研究解决了这个问题。结果表明，当目标声音之前出现的适配声音被感知为明显不连续时，比当它之前出现的适配声音被听到（虚幻地或真实地）连续时，更有可能被评为“连续”。检测理论分析表明，这些对比后的效果反映了感觉和决策过程的结合。即使适配器和目标呈现于对侧耳朵，这种对比的感觉后效仍然存在，这表明其在接收双耳输入的结构中具有神经起源。最后，被评为“连续”的物理上相同但感知上模棱两可的适配器比被评为“不连续”的适配器引起更多的目标连续性报告。这种同化后效纯粹是决策性的。这些发现证实了听觉连续性的判断可以受到先前事件的影响，并揭示了这些后效既有感觉成分又有决策成分。
