Control analysis of optogenetics and deep brain stimulation targeting basal ganglia for Parkinson's disease

Interested in the regulatory effects of emerging optogenetics and classical deep brain stimulation (DBS) on Parkinson's disease (PD), through analysis of thalamic fidelity, here we conduct systematic work with the help of biophysically-based basal ganglia-thalamic circuits model. Under the excitatory ChannelRhodopsin-2 (ChR2), results show that photostimulation targeting globus pallidus externa (GPe) can restore the thalamic relay ability, reduce the synchrony of neurons and alleviate the excessive beta band oscillation, while the effects of targeting globus pallidus interna (GPi) and subthalamic nucleus (STN) are poor. To our delight, these results match experimental reports that the symptoms of PD's movement disorder can be alleviated effectively when GPe are excited by optogenetic, but the situation for STN is not satisfactory. For DBS, we also get considerable simulation results after stimulating GPi, STN and GPe. And the control effect of targeting GPe is better than that of GPi as revealed in some experiments. Furthermore, to reduce side effects and electrical energy, six different dual target combination stimulation strategies are compared, among which the combination of GPe and GPi is the best. Most noteworthy, GPe is shown to be a potential target for both electrical and photostimulation. Although these results need further clinical and experimental verification, they are still expected to provide some enlightenment for the treatment of PD.