Involvement of the Basal Ganglia and Cerebellar Motor Pathways in the Preparation of Self-Initiated and Externally Triggered Movements in Humans

Abstract

The subthalamic nucleus (STN) is part of the cortico-basal ganglia (BG)-thalamocortical circuit, whereas the ventral lateral nucleus of the thalamus (VL) is a relay nucleus in the cerebello-dentato-thalamocortical (CTC) pathway. Both pathways have been implicated in movement preparation. We compared the involvement of the STN and VL in movement preparation in humans by recording local field potentials (LFPs) from seven patients with Parkinson's disease with deep-brain stimulation (DBS) electrodes in the STN and five patients with tremor and electrodes in VL. LFPs were recorded from DBS electrodes and scalp electrodes simultaneously while the patients performed self-paced and externally cued (ready, go/no-go) movements. For the self-paced movement, a premovement-related potential was observed in all patients from scalp, STN (phase reversal, five of six patients), and VL (phase reversal, five of five patients) electrodes. The onset times of the potentials were similar in the cortex, STN, and VL, ranging from 1.5 to 2 s before electromyogram onset. For the externally cued movement, an expectancy potential was observed in all patients in cortical and STN electrodes (phase reversal, six of six patients). The expectancy potential was recorded from the thalamic electrodes in four of five patients. However, phase reversal occurred only in one case, and magnetic resonance imaging showed that this contact was outside the VL. The cortico-BG-thalamocortical circuit is involved in the preparation of both self-paced and externally cued movements. The CTC pathway is involved in the preparation of self-paced but not externally cued movements, although the pathway may still be involved in the execution of these movements.

Effective connectivity of brain networks during self-initiated movement in Parkinson's disease

“…The cerebellum is also important in preparation or execution of self-initiated movements (Sasaki et al, 1979;Ikeda et al, 1994;Ohishi et al, 2003;Purzner et al, 2007). The cerebellum is also involved in generating accurate timing of movements (Dreher and Grafman 2002;Kawashima et al 2000;Rao et al 1997), which is important for selfpaced movements.…”

Movement related potentials and oscillatory activities in the human internal globus pallidus during voluntary movements

“…In the BG, MRPs were observed in the subthalamic nucleus (STN) 6 7. In the GPi, MRP was reported in two patients with epilepsy8 but only referential recording was used and there was no phase reversal between adjacent electrode contacts separated by 1.5 mm.…”

Readiness Discharge for Spontaneous Initiation of Walking in Crayfish

“…It still remains open whether the potential itself represents the volition or the free will of the subject (Gomes, 1999), but it is an established fact that neuronal activities that precede the onset of self-initiated behavior can be recorded in specific regions of the primate brain, apparently corresponding to the readiness potential (Schultz et al, 1997;Purzner et al, 2007). In vertebrates, electrophysiological data on the neuronal activity related to the self-initiated voluntary behavior have accumulated extensively (Schultz, 2000;Schall, 2001;Maimon and Assad, 2006;Tanji and Hoshi, 2008).…”