人工前庭神经调控策略优化设计

Optimal design of neural modulation strategy of vestibular prosthesis

目的:揭示半规管神经元在非线性感知区间内的响应特性,构建精准的前庭神经信息编码模型,实现人工前庭神经调控策略的优化设计。方法:在非线性感知区间内记录半规管神经元对旋转刺激的感知电生理信息数据;采用非线性最小二乘法运算对数据进行拟合,构建线性-非线性模型,通过Akaike信息准则量化优选编码模型及其表达函数。结果:本研究在非线性感知区间内成功采集半规管神经元的电生理信息数据;在频率实验中,超过85%的半规管神经元的精准信息编码模型为非线性,刺激频率对信息编码模型的信息转换影响不显著(P>0.05);在振幅实验中,当振幅>80 deg/s时,超过83.33%的半规管神经元精准信息编码模型为非线性,振幅对信息编码模型的信息转换特性影响显著(P=0.038)。结论:半规管神经元在非线性感知区间内的信息编码模型函数在不同的角速度范围内呈现线性与非线性函数的偏好性选择,而二次多项式函数对信息编码模型的阐述更具优势,可用于优化设计人工前庭神经调控策略。

Objective:To reveal the response characteristics of semicircular canal neurons(SCN)in the nonlinear perceptual interval,and to establish and screen out the precise SCN information coding model and function expression,which lays a foundation for the optimization and improvement of neuromodulation strategy of multichannel vestibular prosthesis.Method:The perceptual electrophysiological information data of the SCNs during the rotational stimulation was recorded in the nonlinear perceptual interval.The nonlinear least-squares algorithm was used to fit the electrophysiological information data to establish the linear-nonlinear models.The Akaike information criterion was used to calculate the goodness of fit of each model to determine the optimal expression function.Result:In the frequency experiment,the accurate information coding model of more than 85%of SCNs is a quadratic polynomial,and the frequency has no significant effect on the linear-nonlinear selection of the SCNs information coding model(P>0.05).In the amplitude experiment,the accurate information coding model of more than 83.33%of SCNs is quadratic polynomial when the maximum angular velocity is>80 deg/s,and the amplitude has a significant effect on the linear-nonlinear selection of the SCNs information coding model(P=0.038).Conclusion:The information coding models of SCN population in the nonlinear perceptual interval have two expressions,linear and nonlinear function,which is closely related to angular velocity.The quadratic polynomial function is more accurate and more advantageous and it can be used to design the precise neuromodulation strategy of multichannel vestibular prosthesis.