基于皮质内神经信号的猕猴运动感觉行为评价技术初探

Tentative evaluation of sensorimotor behavior in rhesus monkeys based on intracortical neural information

目的针对脑瘫、帕金森病等严重影响患者运动、感觉能力的神经性疾病,尝试建立面向非人灵长类动物的、能同时评价运动功能、感觉功能的行为学体系,探索通过行为学数据和电生理学数据评价治疗神经性疾病的药物疗效的可行性。方法设计了一种面向猕猴的、能同时评价运动和感觉功能的实验装置,在猕猴大脑的初级感觉皮质(S1)、初级运动皮质(M1)和后顶叶皮质(PPC)植入微电极阵列,记录猕猴在完成运动、感觉相关的行为任务时的皮质内神经信号,对行为学数据、动作电位信号(spike)和局部场电位信号(LFP)进行统计与解析。结果建立了全新的能同时评价运动与感觉能力的实验平台,实现了对行为学数据与电生理学数据的同步采集与分析。结果显示,运动感觉功能正常的猕猴经过训练后完成任务的成功率为94.96%;不同脑区的神经元具有不同的发放模式,同一神经元的spike发放率在不同的行为阶段会发生变化;单脑区和脑区间的LFP在β频段的相干性会随运动阶段和抓握物体大小的变化发生显著改变。结论任务成功率和平均运动时间能评价触觉分辨与运动能力的改变;单神经元spike发放率变化能评价单神经元活动强度的变化;LFP信号间的相干性改变能间接反映脑区之间的信息交互能力的变化。该文设计了一种新的能同时评价运动能力、感觉能力及相关脑神经信息交互能力的体系,为相关神经药物评价提供了潜在的多层面评价技术。

Objective In view of cerebral palsy,Parkinson′s disease and other neurological diseases that seriously affect patients′motor and sensory abilities,to establish a behavioral system that can simultaneously evaluate motor and sensory functions for nonhuman primates,and explore the feasibility of evaluating the efficacy of drugs for neurological diseases through behavioral and electrophysiological data.Methods An experimental device was designed for rhesus macaques that could simultaneously evaluate motor and sensory functions.Microelectrode arrays were implanted in the primary sensory cortex(S1),primary motor cortex(M1)and posterior parietal cortex(PPC)to record the neural signals in the cortex when rhesus macaques completed behavioral tasks related to motor and sensory functions.The behavioral data,actional potential(spike)and local field potential(LFP)were analyzed.Results A new experimental platform was established to simultaneously evaluate the motor and sensory abilities,and the simultaneous behavioral data and electrophysiological data were recorded and analyzed.The results showed that after training,the success rate of monkeys with normal sensorimotor function was 94.96%.Neurons in different cortices had different firing patterns,and spike firing rate of the same neuron changed in different behavior phases.The coherance of LFP(βband)in a single cortex or between two cortices changed significantly with the movement phase and the size of grasping objects.Conclusion Task success rates and average motion time can help evaluate the ability of sensory discrimination and motor.The firing rate of a single neuron can evaluate the change in activity intensity.The changes in coherence between LFP(βband)can indirectly reveal the changes in the information interaction ability between cortices.This paper has designed a new system that could simultaneously evaluate the ability of sensorimotor and neural information interaction between related cortices,and provide a potential multilevel evaluation technique for neuropathic drugs.