大脑中的神经相互作用受到传输延迟的影响,传输延迟可能会在正常和病理条件下严重改变信号在不同大脑区域的传播。理论和计算模型已广泛研究了相互作用延迟对通用神经网络动力学的影响。然而,在帕金森病(PD)的基底节区(BG)病理性振荡动力学的发展中,传输延迟的作用被忽视。
■这里,我们通过使用Wilson-Cowan(WC)平均场激发率模型,研究了传输延迟对控制(正常)和PD状态下BG网络的放电率和振荡功率的影响。我们还探讨了在控制和PD条件下,传输延迟如何影响BG对皮层刺激的反应。
■我们的结果表明,在控制条件下,BG对皮层刺激的振荡反应对种群间延迟的变化是稳健的,并且仅取决于相对于皮层活动的刺激阶段。在PD条件下,然而,传输延迟对异常α(8-13Hz)和β波段(13-30Hz)振荡的出现至关重要,这表明延迟在帕金森病BG的异常节律发生中起重要作用。
■我们的发现表明,除了BG核内部和之间的连接强度外,帕金森病BG的振荡动力学也可能受到种群间传输延迟的影响。此外,BG对皮质刺激的反应的相位特异性可以进一步深入了解延迟在相位特异性脑刺激治疗的计算优化中的潜在作用。
UNASSIGNED: Neural interactions in the brain are affected by transmission delays which may critically alter signal propagation across different brain regions in both normal and pathological conditions. The effect of interaction delays on the dynamics of the generic neural networks has been extensively studied by theoretical and computational models. However, the role of transmission delays in the development of pathological oscillatory dynamics in the basal ganglia (BG) in Parkinson\'s disease (PD) is overlooked.
UNASSIGNED: Here, we investigate the effect of transmission delays on the discharge rate and oscillatory power of the BG networks in control (normal) and PD states by using a Wilson-Cowan (WC) mean-field firing rate model. We also explore how transmission delays affect the response of the BG to cortical stimuli in control and PD conditions.
UNASSIGNED: Our results show that the BG oscillatory response to cortical stimulation in control condition is robust against the changes in the inter-population delays and merely depends on the phase of stimulation with respect to cortical activity. In PD condition, however, transmission delays crucially contribute to the emergence of abnormal alpha (8-13 Hz) and beta band (13-30 Hz) oscillations, suggesting that delays play an important role in abnormal rhythmogenesis in the parkinsonian BG.
UNASSIGNED: Our findings indicate that in addition to the strength of connections within and between the BG nuclei, oscillatory dynamics of the parkinsonian BG may also be influenced by inter-population transmission delays. Moreover, phase-specificity of the BG response to cortical stimulation may provide further insight into the potential role of delays in the computational optimization of phase-specific brain stimulation therapies.