Angenstein Nicole, Brechmann André
Leibniz Institute for Neurobiology, Brenneckestr. 6, Magdeburg, 39118, Germany.
Hum Brain Mapp. 2017 Sep;38(9):4459-4469. doi: 10.1002/hbm.23673. Epub 2017 Jun 5.
Previous studies on active duration processing on sounds showed opposing results regarding the predominant involvement of the left or right hemisphere. Duration of an acoustic event is normally judged relative to other sounds. This requires sequential comparison as auditory events unfold over time. We hypothesized that increasing the demand on sequential comparison in a task increases the involvement of the left auditory cortex. With the current fMRI study, we investigated the effect of sequential comparison in active duration discrimination by comparing a categorical with a comparative task. During the categorical task, the participant had to categorize the tones according to their duration (short vs long). During the comparative task, they had to decide for each tone whether its length matched the tone presented before. We used the contralateral noise procedure to reveal the degree of participation of the left and right auditory cortex during these tasks. We found that both tasks more strongly involve the left than the right auditory cortex. Furthermore, the left auditory cortex was more strongly involved during comparison than during categorization. Together with previous studies, this suggests that additional demand for sequential comparison during processing of different basic acoustic parameters leads to an increased recruitment of the left auditory cortex. In addition, the comparison task more strongly involved several brain areas outside the auditory cortex, which may also be related to the demand for additional cognitive resources as compared to the more efficient categorization of sounds. Hum Brain Mapp 38:4459-4469, 2017. © 2017 Wiley Periodicals, Inc.
先前关于声音持续时间处理的研究在左半球或右半球的主要参与方面显示出相反的结果。声音事件的持续时间通常是相对于其他声音来判断的。这需要在听觉事件随时间展开时进行顺序比较。我们假设，在一项任务中增加顺序比较的需求会增加左听觉皮层的参与度。在当前的功能磁共振成像（fMRI）研究中，我们通过比较分类任务和比较任务，研究了顺序比较在主动持续时间辨别中的作用。在分类任务中，参与者必须根据音调的持续时间（短与长）对其进行分类。在比较任务中，他们必须为每个音调判断其长度是否与之前呈现的音调匹配。我们使用对侧噪声程序来揭示在这些任务中左、右听觉皮层的参与程度。我们发现，与右听觉皮层相比，这两项任务都更强烈地涉及左听觉皮层。此外，左听觉皮层在比较过程中的参与程度比分类过程中更强。与先前的研究一起，这表明在处理不同基本声学参数时对顺序比较的额外需求会导致左听觉皮层的募集增加。此外，比较任务更强烈地涉及听觉皮层以外的几个脑区，这也可能与与更高效的声音分类相比对额外认知资源的需求有关。《人类大脑图谱》38:4459 - 4469，2017年。©2017威利期刊公司。
