时距记忆提取阶段的脑电信号研究

Electroencephalogram in the stage of temporal memory retrieval

目的对时距记忆提取阶段的行为学指标以及脑电信号在不同提取次数下的变化规律进行探讨。方法随机抽取2022年11月招募的上海理工大学健康被试30名, 采用时间估计任务的再现法, 记录被试1 500 ms时距记忆提取阶段的反应时间和脑电信号, 计算记忆错误率、精度和准确度以及脑电信号低频段功率, 进行时频分析和溯源分析, 并对记忆错误率、精度与θ、β节律的相关性进行pearson相关性分析。结果时间差和记忆精度在提取次数间存在主效应[F(3, 1 196)=2.932, P=0.033;F(3, 1 196)=3.191, P=0.026], 且随着提取次数的增加而变大。记忆准确度不存在主效应, 但随着提取次数增加, 准确度均值变大。随着记忆提取次数增加, 左侧额叶的θ节律功率逐渐变大[F(3, 116)=2.668, P=0.035], 额中叶β节律平均功率逐渐减小[F(3, 116)=2.810, P=0.029]。上顶叶体感联合皮层(BA7)、背外侧前额叶(BA9)和前运动皮层(BA6)脑区在第1次与第2次、第2次与第3次、第3次与第4次记忆提取中的电流密度分布差异均出现了增加(P<0.01)。θ节律与记忆精度呈正相关(r=0.258, P<0.05), β节律与记忆精度呈负相关(r=?0.404, P<0.01)。结论时距记忆提取阶段, 增加时距记忆的提取次数会提高记忆错误率和精度, 记忆精度与左侧额叶θ节律功率增加以及额中央区域β节律减小有关。

ObjectiveTo explore the changes in behavioral indexes and electroencephalogram(EEG)in the stage of temporal memory retrieval under different extraction times.MethodsA total of 30 healthy subjects were randomly selected from Shanghai University of Science and Technology in November 2022.The reaction time and EEG of the subjects in the 1500 ms stage of temporal memory retrieval were recorded by a reproduction method of time estimation task.The memory error rate,precision,accuracy,and low-frequency power of EEG were calculated,and time-frequency analysis and traceability analysis were carried out.Pearson correlation analysis was used to analyze the correlation between memory error rate,accuracy,θrhythm,andβrhythm.ResultsThe main effects of time difference and memory precision between retrieval times were found[F(3,1196)=2.932,P=0.033;F(3,1196)=3.191,P=0.026],and they increased with the extraction times.There was no main effect on memory accuracy,but as the number of extractions increases,the average accuracy increased.With the increase in memory retrieval times,the power ofθrhythm in the left frontal lobe gradually increased[F(3,116)=2.668,P=0.035],and the average power ofβrhythm in the middle frontal lobe gradually decreased[F(3,116)=2.810,P=0.029].The differences in current density distribution in the somatosensory cortex(BA7),dorsolateral prefrontal cortex(BA9),and premotor cortex(BA6)increased in the first and second,second and third,and third and fourth memory retrievals(P<0.01).Theθrhythm was positively correlated with memory accuracy(r=0.258,P<0.05),and theβrhythm was negatively correlated with memory precision(r=−0.404,P<0.01).ConclusionsIn the stage of temporal memory extraction,increasing the number of temporal memory extraction times can reduce the memory error rate and improve accuracy.Memory accuracy is related to the power of theθrhythm in the left frontal lobe and the power of theβrhythm in the middle frontal lobe.