A simultaneous EEG-fMRI study of thalamic load-dependent working memory delay period activity.
A simultaneous EEG-fMRI study of thalamic load-dependent working memory delay period activity.
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DOI：
10.3389/fnbeh.2023.1132061
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发表时间：
2023
影响因子：
3
通讯作者：
中科院分区：
文献类型：
--
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工作记忆（WM）是执行功能的重要组成部分，它依赖于在存在或不存在干扰刺激的情况下在短时间内在线维护与任务相关的信息。主动维持发生在 WM 延迟期，即刺激编码和随后检索之间的时间。先前的研究已经广泛记录了 WM 延迟期间的前额叶和后顶叶皮层活动，但包括丘脑在内的皮层下结构的作用仍有待充分阐明，特别是在人类中。使用同步脑电图 (EEG) 功能磁共振成像 (fMRI) 方法，我们研究了丘脑在 WM 延迟期间的作用，采用修改后的 Sternberg 范式，遵循自然场景的低和高记忆负载编码。在延迟期间，参与者被动地观看包含相似颜色和空间频率的混乱场景，作为感知基线。个体源估计通过丘脑功能磁共振成像信号相对于 WM 延迟期开始的位置进行加权。延迟期开始后 160-390 毫秒，在丘脑双侧观察到记忆负荷对维持的影响，低负荷条件下的脑电图源振幅高于高负荷条件。主要发现是，尽管感知输入和即将到来的运动需求的持续时间相似，但与高条件相比，丘脑激活在低条件下升高，这表明在刺激巩固到WM过程中丘脑的感觉过滤作用有限，其中当延迟期间存在干扰感知刺激的情况下需要维持较少的刺激时，会出现最高活动。研究结果在有关丘脑在工作记忆期间感觉门控中的作用的理论背景下进行了讨论。
Working memory (WM) is an essential component of executive functions which depend on maintaining task-related information online for brief periods in both the presence and absence of interfering stimuli. Active maintenance occurs during the WM delay period, the time between stimulus encoding and subsequent retrieval. Previous studies have extensively documented prefrontal and posterior parietal cortex activity during the WM delay period, but the role of subcortical structures including the thalamus remains to be fully elucidated, especially in humans. Using a simultaneous electroencephalogram (EEG)-functional magnetic resonance imaging (fMRI) approach, we investigated the role of the thalamus during the WM delay period in a modified Sternberg paradigm following low and high memory load encoding of naturalistic scenes. During the delay, participants passively viewed scrambled scenes containing similar color and spatial frequency to serve as a perceptual baseline. Individual source estimation was weighted by the location of the thalamic fMRI signal relative to the WM delay period onset. The effects memory load on maintenance were observed bilaterally in thalamus with higher EEG source amplitudes in the low compared to high load condition occurring 160–390 ms after the onset of the delay period. The main finding that thalamic activation was elevated during the low compared to high condition despite similar duration of perceptual input and upcoming motor requirements suggests a capacity-limited role for sensory filtering of the thalamus during consolidation of stimuli into WM, where the highest activity occurs when fewer stimuli need to be maintained in the presence of interfering perceptual stimuli during the delay. The results are discussed in the context of theories regarding the role of the thalamus in sensory gating during working memory.
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影响因子：
56.9
作者：
FUSTER, JM;ALEXANDER, GE
通讯作者：
ALEXANDER, GE
影响因子：
5.7
作者：
Ou, Wanmei;Nummenmaa, Aapo;Golland, Polina
通讯作者：
Golland, Polina
DOI：
10.1073/pnas.1106439108
发表时间：
2011-10-18
影响因子：
11.1
作者：
Feredoes, Eva;Heinen, Klaartje;Driver, Jon
通讯作者：
Driver, Jon
DOI：
10.1016/0013-4694(94)90094-9
发表时间：
1994-03-01
期刊：
ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY
影响因子：
--
作者：
BERG, P;SCHERG, M
通讯作者：
SCHERG, M
影响因子：
64.5
作者：
Hsiao K;Noble C;Pitman W;Yadav N;Kumar S;Keele GR;Terceros A;Kanke M;Conniff T;Cheleuitte-Nieves C;Tolwani R;Sethupathy P;Rajasethupathy P
通讯作者：
Rajasethupathy P