Increased facilitation of the primary motor cortex in de novo Parkinson's disease

Paired-pulse transcranial magnetic stimulation (TMS) is useful to estimate the balance between inhibitory and facilitatory circuits of the primary motor cortex (M1) in Parkinson's disease (PD). Results of earlier studies are, however, incongruent: some reports describe normal short-interval intracortical inhibition (SICI), but others describe reduced SICI. We hypothesize that exaggerated intracortical facilitation masks normal inhibition, and that a triple-pulse method can reveal masked inhibition in PD.

Source: Parkinsonism and Related Disorders - July 17, 2019 Category: Neurology Authors: Yuichiro Shirota, Shinya Ohminami, Ryosuke Tsutsumi, Yasuo Terao, Yoshikazu Ugawa, Shoji Tsuji, Ritsuko Hanajima Source Type: research