CAJ | 학술논문

目的研究大鼠在Y迷宫记忆过程中,责任脑区前额叶皮层记录的局部场电位的熵编码,为研究工作记忆的神经编码机制提供计算支持.方法实验数据:本研究所用的实验数据为4只SD大鼠在Y迷宫工作记忆过程和静息状态下前额叶皮层的各20次16通道局部场电位(LFPs)数据(其中10次正确,10次错误),由天津医科大学医学神经生物学实验室提供;LFPs预处理:对LFPs去除工频干扰和基线漂移;LFPs的时频分析与特征频段的提取:通过多窗口傅里叶变换,观察能量分布的主要频段,并通过带通滤波提取特征频段的场电位信号;16通道LFPs的熵编码:选取生理窗口为500 ms,窗口移动步长为125 ms,对LFPs数据序列加窗,计算每个滑动窗口内的熵值并平均,进而观察信息熵的变化趋势.结果 LFPs时频分布表明工作记忆期间其能量主要集中在θ频段(4～12 Hz);θ频段LFPs在正确工作记忆实验中,工作记忆参考点前ls熵的平均值为0.939±0.020,显著大于静息状态的值(0.795±0.031),其差异具有统计学意义(P＜0.05);而错误实验中工作记忆事件前后信息熵值无差别,未编码工作记忆事件.结论 θ频段(4～12 Hz)是工作记忆的特征频段;θ频段LFPs的熵有效地编码了工作记忆事件.
목적 연구대서재Y미궁기억과정중,책임뇌구전액협피층기록적국부장전위적적편마,위연구공작기억적신경편마궤제제공계산지지.방법 실험수거:본연구소용적실험수거위4지SD대서재Y미궁공작기억과정화정식상태하전액협피층적각20차16통도국부장전위(LFPs)수거(기중10차정학,10차착오),유천진의과대학의학신경생물학실험실제공;LFPs예처리:대LFPs거제공빈간우화기선표이;LFPs적시빈분석여특정빈단적제취:통과다창구부리협변환,관찰능량분포적주요빈단,병통과대통려파제취특정빈단적장전위신호;16통도LFPs적적편마:선취생리창구위500 ms,창구이동보장위125 ms,대LFPs수거서렬가창,계산매개활동창구내적적치병평균,진이관찰신식적적변화추세.결과 LFPs시빈분포표명공작기억기간기능량주요집중재θ빈단(4～12 Hz);θ빈단LFPs재정학공작기억실험중,공작기억삼고점전ls적적평균치위0.939±0.020,현저대우정식상태적치(0.795±0.031),기차이구유통계학의의(P＜0.05);이착오실험중공작기억사건전후신식적치무차별,미편마공작기억사건.결론 θ빈단(4～12 Hz)시공작기억적특정빈단;θ빈단LFPs적적유효지편마료공작기억사건.
Objective Toinvestigatetheentropyoflocalfieldpotentials(LFPs)recordedinratmedialprefrontal cortex during a Y-maze working memory (WM) task, to provide computing support for neural coding mechanism.Methods Sixteen-channel LFPs were recorded from SD rats while they performed a Y-maze WM task.The data came from 4 rats, 20 trials (10 correct trials and 10 incorrect trials) per rat provided by laboratory of neurobiology in medicine,Tianjin Medical University.Original LFPs were preprocessed to remove 50 Hz power line noise and baseline drift.Multi-taper Fourier transform was applied to calculate spatial distributions of LFPs and band pass filter were used to extract characteristic signal.The entroy coding of 16 channel LFPs was as follows: the physiological window was set to be 500 ms, the step length of physiological window was set to be 125 ms, windows were added to LFPs data, and then LFPs entropy of each sliding window was computed and averaged to get the trend of multichannel entropy values duringthe WM task.Results The power of θ band (4-12 Hz) in LFPs increased.The averaged entropy value ofmultichannel θ band LFPs in correct trials was 0.939±-0.020, which were larger than those in the resting state, 0.795±0.031 (P＜0.05).Those during wrong WM task had no significant difference, which didn't encode the WM task.Conclusions The principal frequency band related to WM is the θ band and LFPs entropy encodes the WM effectively.