Johnson Blake W, Hautus Michael J, Duff Damien J, Clapp Wes C
Research Centre for Cognitive Neuroscience, Department of Psychology, University of Auckland, Auckland, New Zealand.
Psychophysiology. 2007 Jul;44(4):541-51. doi: 10.1111/j.1469-8986.2007.00535.x. Epub 2007 May 22.
Cortical processing of interaural timing differences (ITDs) was investigated with event-related potential (ERP) measurements in 16 human participants who were required in separate tasks to detect or to spatially localize dichotically embedded pitches. ITDs elicited three ERP components labeled ORN, N2, and P400. The ORN occurred at a latency of 150-250 ms and was elicited by ITDs regardless of location or task. In contrast, the N2 response (250-350 ms) was strongly modulated by location and showed larger amplitudes for the localization task than for the detection task. Finally, ITDs in the detection task elicited a P400 at a latency of 400-500 ms, but this response was entirely absent from ERPs elicited by identical stimuli in the localization task. These results are consistent with a sequential model of auditory perception in which segregation of concurrent sounds is followed by domain-specific processing of object location and identity.
通过事件相关电位（ERP）测量，对16名人类参与者的双耳时间差（ITD）的皮质处理进行了研究。这些参与者被要求在不同任务中检测或在空间上定位双耳嵌入的音调。ITD引发了三个ERP成分，分别标记为ORN、N2和P400。ORN出现在150 - 250毫秒的潜伏期，并且无论位置或任务如何，均由ITD引发。相比之下，N2反应（250 - 350毫秒）受到位置的强烈调制，并且在定位任务中显示出比检测任务更大的振幅。最后，检测任务中的ITD在400 - 500毫秒的潜伏期引发了P400，但在定位任务中相同刺激引发的ERP中完全没有这种反应。这些结果与听觉感知的顺序模型一致，在该模型中，同时发生的声音先进行分离，然后是对物体位置和身份的特定领域处理。
