On the Role of Arkypallidal and Prototypical Neurons for Phase Transitions in the External Pallidum

0546897 - ÚI 2022 US eng J - Článek v odborném periodiku
Gast, R. - Gong, R. - Schmidt, Helmut - Meijer, G. - Knösche, T.R.
On the Role of Arkypallidal and Prototypical Neurons for Phase Transitions in the External Pallidum.
Journal of Neuroscience. Roč. 41, č. 31 (2021), s. 6673-6683. ISSN 0270-6474. E-ISSN 1529-2401
Klíčová slova: globus-pallidus * basal ganglia * subthalamic nucleus * parkinsons-disease * beta oscillations * response curve * network * spiking * model * synchronization * basal ganglia * neural network * oscillations * pallidum * Parkinson * phase-amplitude coupling
Impakt faktor: 6.709, rok: 2021

The external pallidum (globus pallidus pars externa [GPe]) plays a central role for basal ganglia functions and dynamics and, consequently, has been included in most computational studies of the basal ganglia. These studies considered the GPe as a homogeneous neural population. However, experimental studies have shown that the GPe contains at least two distinct cell types (prototypical and arkypallidal cells). In this work, we provide in silico insight into how pallidal heterogeneity modulates dynamic regimes inside the GPe and how they affect the GPe response to oscillatory input. We derive a mean-field model of the GPe system from a microscopic spiking neural network of recurrently coupled prototypical and arkypallidal neurons. Using bifurcation analysis, we examine the influence of dopamine-dependent changes of intrapallidal connectivity on the GPe dynamics. We find that increased self-inhibition of prototypical cells can induce oscillations, whereas increased inhibition of prototypical cells by arkypallidal cells leads to the emergence of a bistable regime. Furthermore, we show that oscillatory input to the GPe, arriving from striatum, leads to characteristic patterns of cross-frequency coupling observed at the GPe. Based on these findings, we propose two different hypotheses of how dopamine depletion at the GPe may lead to phase-am-plitude coupling between the parkinsonian beta rhythm and a GPe-intrinsic gamma rhythm. Finally, we show that these findings generalize to realistic spiking neural networks of sparsely coupled Type I excitable GPe neurons.
Trvalý link: http://hdl.handle.net/11104/0323283