The N100 auditory cortical evoked potential indexes scanning of auditory short-term memory
The N100 auditory cortical evoked potential indexes scanning of auditory short-term memory
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DOI：
10.1016/s1388-2457(99)00183-2
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发表时间：
1999-12-01
影响因子：
4.7
通讯作者：
Starr, A
中科院分区：
文献类型：
--
作者：
Conley, EM;Michalewski, HJ;Starr, A
目的：研究听觉诱发电位N100和P200成分在短时记忆记忆和扫描过程中所反映的听觉皮层活动。方法：在一项记忆任务中，被试将一个探测手指归类为先前提出的1、3、5和7项数字列表中的一项或非一项。为了进行比较，数字任务中的受试者听了一系列数字，就像记忆任务中的数字一样，但只确定探测数字是奇数还是常数。从头皮电极记录对陈述列表和对探针的诱发电位，并分别对两种任务进行平均。结果：呈现集合项目的N100波幅受记忆中集合大小的影响，但在数字任务中不受集合大小的影响；1个项目集合的N100波幅大于3、5、7个项目集合。P200在记忆任务和数字任务中的波幅均呈线性增加。对于探测项目，N100而不是P200的波幅随着呈现集中的项目数量在记忆中增加而不是数字任务中的增加而呈线性下降。记忆扫描过程中N100波幅的线性变化是插入式探头特有的，而非插入式探头所特有的。在记忆和数字任务中，N_(100)和P_(200)的探测位数几乎都是呈现位数的两倍。结论：人类听觉短时记忆任务中的听觉感觉皮层活动在记忆和记忆扫描过程中均表现出动态变化。(C)1999爱思唯尔科学有限公司。保留所有权利。
Objective: To study activity of auditory cortex reflected by the N100 and P200 components of the auditory evoked potentials during memorization and scanning of short-term memory stores.Methods: In a MEMORY task subjects classified a probe digit either as a member or not a member of a previously presented list of digits that varied in size from one, 3, 5 and 7 items. For comparison, subjects in a NUMBER task listened to a list of digits as in the MEMORY task but determined only whether the probe digit as odd or evert. Evoked potentials to the presentation list and to probes were recorded from scalp electrodes and separately averaged for both tasks. The components peaking at approximately 100 ms (N100) and 200 ms (P200) that reflect activity of primary auditory cortex were identified and peak amplitudes and latencies were measured.Results: For presentation set items, the amplitude of N100 was affected by set size in the MEMORY but not in the NUMBER task; N100 was larger for the one item set than for the 3, 5, and 7 item sets. P200 increased in amplitude in a linear manner for both the MEMORY and NUMBER tasks. For probe items, N100 but not P200 amplitude decreased in a linear manner as the number of items in the presentation set increased in the MEMORY but not in the NUMBER task. The linear change of N100 amplitude during memory scanning was particular to inset but not to out-of-set probes. The amplitudes of both N100 and P200 were almost twice as large in probe digits than in the digits in the presentation set in both the MEMORY and NUMBER tasks.Conclusion: Auditory sensory cortical activity in humans during an auditory short-term memory task shows dynamic changes during both memorization and memory scanning. (C) 1999 Elsevier Science Ltd. All rights reserved.