The effects of cortical inputs on the oscillation and synchronization of the basal ganglia

The basal ganglia (BG) is critical for motor control, and its rhythmic oscillation is closely linked to movement disorders such as Parkinson’s disease (PD) etc. This study applied a dynamic model of the cortex (CTX) - BG network to investigate how distinct cortical inputs modulated network oscillations and synchronization of BG by focusing on the output activity of the internal globus pallidus (GPi). Cross-correlation analysis revealed that chattering-type cortical neurons produced the strongest resonance with GPi (correlation coefficient up to 0.52), especially when oscillating in the beta frequency band. Among the three major pathways, the direct pathway exerted the greatest influence on GPi oscillations (influence index R = 24.1), compared to the indirect and hyperdirect pathways. Principal component analysis showed that increasing the strength of the cortico-striatal connection enhanced GPi synchrony, and pathological input could trigger PD-like pathological beta oscillations. Importantly, selective disruption of cortical input to D1-type medium spiny neuron (D1-MSN) markedly reduced pathological oscillations in GPi, which suggested it was a potential therapeutic strategy. Specifically, our results revealed that targeted reduction of cortical input to the direct pathway might represent a novel therapeutic approach for attenuating pathological β synchronization in PD. These findings quantitatively elucidate how cortical input patterns and pathways regulate BG output, which provides new insights for targeted interventions in movement disorders.