经颅磁刺激模式差异性对大鼠工作记忆神经网络关联特性的影响研究

Effect of Different Patterns of Transcranial Magnetic Stimulation on the Correlation of Neural Network During Working Memory Task of Rats

经颅磁刺激(TMS)技术因具有无痛无创和非侵入式等特点已被广泛应用于临床神经功能调控领域。工作记忆是重要的认知神经功能,但TMS对工作记忆功能的影响机制尚不清晰,且各模式TMS对认知功能的影响差异较大。因此,探究TMS技术对工作记忆(WM)的调控机制有重要的临床意义。首先,该文将成年Wistar大鼠分为空白对照(control)组、重复经颅磁刺激(rTMS)组、连续性Theta节律刺激(cTBS)组及间断性Theta节律刺激(iTBS)组;然后,利用在体多通道技术采集四组大鼠执行T迷宫工作记忆任务过程中前额叶皮层(PFC)的局部场电位信号(LFPs);最后,通过对比分析四组大鼠WM任务过程中的行为学差异、LFPs的相关性及LFPs网络连接特性等,探索不同模式经颅磁刺激技术大鼠WM中神经网络的影响。结果表明,刺激组大鼠达到WM任务“学会”标准所用时间均少于空白对照组(P<0.05);刺激组LFPs信号电极对间的相关性显著高于空白对照组;刺激组LFPs信号的网络连接密度显著增大(P<0.05)且全局效率显著增大(P<0.05)。因此,iTBS、cTBS及rTMS均能在一定程度上改善成年Wistar大鼠PFC中神经元集群之间的关联同步性,其中,iTBS的改善效果最为明显。该文为进一步探索经颅磁刺激技术对工作记忆的影响机制提供理论支持。

Transcranial magnetic stimulation(TMS)has been widely used in clinical neurologic regulation due to its painless and noninvasive characteristics.Working memory(WM)is an important cognitive function,but the effect mechanism of TMS on working memory function is still unclear and the influence of TMS with various modes on the nervous system is quite different.Therefore,it is of great clinical significance to explore the effect mechanism of TMS on working memory.In this paper,adult Wistar rats were divided into control group,repetitive transcranial magnetic stimulation(rTMS)group,continuous Theta burst stimulation(cTBS)group and intermittent Theta burst stimulation(iTBS)group.The local field potential signals(LFPs)of prefrontal cortex(PFC)in the four groups were collected synchronously by implanting multichannel electrodes in vivo during the T-maze working memory task.Finally,the effects of different modes of TMS on neural network in working memory were explored by comparative analysis of the behavioral differences,the correlation of LFPs and the network connection characteristics of LFPs in the four groups.The behavioral results showed that the time for the rats in the stimulation groups to reach the task correction criterion was less than that of the control group(P<0.05).The correlation results showed that the correlation coefficient of LFPs between electrode pairs in the stimulation model group was higher than that in the control group.The network connection density and the global efficiency of LFPs obviously increased in the stimulation group(P<0.05).In conclusion,iTBS,cTBS and rTMS can improve the association synchronization of PFC in adult Wistar rats to a certain extent,and the improvement effect of iTBS is the best,which can provide theoretical support for further exploring the effect of TMS on WM.