Oscillation Phase Locking and Late ERP Components of Intracranial Hippocampal Recordings Correlate to Patient Performance in a Working Memory Task.
Oscillation Phase Locking and Late ERP Components of Intracranial Hippocampal Recordings Correlate to Patient Performance in a Working Memory Task.
复制标题
颅内海马记录的振荡锁相和晚期 ERP 成分与患者在工作记忆任务中的表现相关。
DOI：
10.3389/fnhum.2016.00287
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发表时间：
2016
影响因子：
2.9
通讯作者：
Lenck-Santini PP
中科院分区：
文献类型：
--
作者：
Kleen JK;Testorf ME;Roberts DW;Scott RC;Jobst BJ;Holmes GL;Lenck-Santini PP
在工作记忆任务中，刺激呈现会导致多个频段内脑内颞叶振荡的重置。为了进一步了解这一现象的功能相关性，我们调查了工作记忆表现是否取决于海马体正在进行的振荡的相位精度。我们记录了执行工作记忆任务的个体的海马区局部场电位。进行了两种类型的试验。对于高记忆试验，呈现四个字母的列表(“列表”)之后是一个单字母记忆探头(“测试”)。低内存负荷试验由四个相同的字母(AAAA)组成，后面是一个带有相同字母(A)的探测器，这些试验散布在一起。在刺激呈现和回忆过程中，在增量(0.5-4赫兹)、西塔(5-7赫兹)和阿尔法(8-12赫兹)频段观察到由成对相位一致性指数(PPCI)估计的持续振荡的显著相位锁定，但在低记忆负荷实验中增加。然而，在所有患者中，左侧海马区回忆过程中较高的增量PPCI与较快的反应时间相关。由于相位锁定也可以解释为刺激诱发电位的结果，我们进行了事件相关电位分析(ERP)，并检查了ERP成分与性能的关系。我们发现，事件相关电位晚期成分的波幅和潜伏期都与反应时和准确性有关。我们认为，在Sternberg任务中，振荡的相位锁定，或其ERP相关，同步了海马区内的网络和与工作记忆有关的连接结构。
In working memory tasks, stimulus presentation induces a resetting of intracranial temporal lobe oscillations in multiple frequency bands. To further understand the functional relevance of this phenomenon, we investigated whether working memory performance depends on the phase precision of ongoing oscillations in the hippocampus. We recorded intra-hippocampal local field potentials in individuals performing a working memory task. Two types of trials were administered. For high memory trials presentation of a list of four letters (“List”) was followed by a single letter memory probe (“Test”). Low memory load trials, consisting of four identical letters (AAAA) followed by a probe with the same letter (A), were interspersed. Significant phase locking of ongoing oscillations across trials, estimated by the Pairwise Phase Consistency Index (PPCI) was observed in delta (0.5–4 Hz), theta (5–7 Hz), and alpha (8–12 Hz) bands during stimulus presentation and recall but was increased in low memory load trials. Across patients however, higher delta PPCIs during recall in the left hippocampus were associated with faster reaction times. Because phase locking could also be interpreted as a consequence of a stimulus evoked potential, we performed event related potential analysis (ERP) and examined the relationship of ERP components with performance. We found that both amplitude and latency of late ERP components correlated with both reaction time and accuracy. We propose that, in the Sternberg task, phase locking of oscillations, or alternatively its ERP correlate, synchronizes networks within the hippocampus and connected structures that are involved in working memory.