Gamble Marissa L, Woldorff Marty G
Duke University.
J Cogn Neurosci. 2015 Sep;27(9):1675-84. doi: 10.1162/jocn_a_00814. Epub 2015 Apr 7.
To make sense of our dynamic and complex auditory environment, we must be able to parse the sensory input into usable parts and pick out relevant sounds from all the potentially distracting auditory information. Although it is unclear exactly how we accomplish this difficult task, Gamble and Woldorff [Gamble, M. L., & Woldorff, M. G. The temporal cascade of neural processes underlying target detection and attentional processing during auditory search. Cerebral Cortex (New York, N.Y.: 1991), 2014] recently reported an ERP study of an auditory target-search task in a temporally and spatially distributed, rapidly presented, auditory scene. They reported an early, differential, bilateral activation (beginning at 60 msec) between feature-deviating target stimuli and physically equivalent feature-deviating nontargets, reflecting a rapid target detection process. This was followed shortly later (at 130 msec) by the lateralized N2ac ERP activation, that reflects the focusing of auditory spatial attention toward the target sound and parallels the attentional-shifting processes widely studied in vision. Here we directly examined the early, bilateral, target-selective effect to better understand its nature and functional role. Participants listened to midline-presented sounds that included target and nontarget stimuli that were randomly either embedded in a brief rapid stream or presented alone. The results indicate that this early bilateral effect results from a template for the target that utilizes its feature deviancy within a stream to enable rapid identification. Moreover, individual-differences analysis showed that the size of this effect was larger for participants with faster RTs. The findings support the hypothesis that our auditory attentional systems can implement and utilize a context-based relational template for a target sound, making use of additional auditory information in the environment when needing to rapidly detect a relevant sound.
为了理解我们动态且复杂的听觉环境，我们必须能够将感官输入解析为可用部分，并从所有可能分散注意力的听觉信息中挑选出相关声音。尽管目前尚不清楚我们究竟是如何完成这项艰巨任务的，但甘布尔和沃尔多夫[甘布尔，M. L.，& 沃尔多夫，M. G. 听觉搜索过程中目标检测和注意力处理背后的神经过程的时间级联。《大脑皮层》（纽约，纽约：1991年），2014年]最近报告了一项关于在时间和空间上分布、快速呈现的听觉场景中的听觉目标搜索任务的ERP研究。他们报告了特征偏离的目标刺激与物理上等效的特征偏离的非目标刺激之间早期的、双侧差异激活（始于60毫秒），这反映了一个快速的目标检测过程。随后不久（在130毫秒）出现了侧向化的N2ac ERP激活，这反映了听觉空间注意力向目标声音的聚焦，并且与视觉中广泛研究的注意力转移过程相似。在这里，我们直接研究了早期的双侧目标选择性效应，以更好地理解其本质和功能作用。参与者聆听中线呈现的声音，这些声音包括随机嵌入简短快速流中或单独呈现的目标和非目标刺激。结果表明，这种早期双侧效应源于一个目标模板，该模板利用其在流中的特征偏差来实现快速识别。此外，个体差异分析表明，对于反应时间较快的参与者，这种效应的大小更大。这些发现支持了这样一种假设，即我们的听觉注意力系统可以为目标声音实施并利用基于上下文的关系模板，在需要快速检测相关声音时利用环境中的额外听觉信息。
