Decoding sequential finger movements from preparatory activity in higher-order motor regions: an fMRI multi-voxel pattern analysis.

Eur J Neurosci. 2015 Sep 5;

Authors: Nambu I, Hagura N, Hirose S, Wada Y, Kawato M, Naito E

Abstract
Performing a complex sequential finger movement requires temporally well-ordered organization of individual finger movements. Previous behavioral studies have suggested that the brain prepares a whole sequence of movements as a single set, rather than the movements of individual fingers. However, direct neuroimaging support for this hypothesis is lacking, and assuming it to be true, which brain regions represent the information of a prepared sequence remains unclear. Here, we measured brain activity with functional magnetic resonance imaging while fourteen right-handed healthy participants performed two types of well-learned sequential finger movements with their right hands. Using multi-voxel pattern analysis, we examined whether the types of the forthcoming sequence could be predicted from the preparatory activities of nine regions of interest, which included motor, somatosensory and posterior parietal regions in each hemisphere, bilateral visual cortices, cerebellum and basal ganglia. We found that, during preparation, the activity of the contralateral motor regions could predict which of the two sequences would be executed. Further detailed analysis revealed that the contralateral dorsal premotor cortex and supplementary motor area were the key areas that contributed to the prediction consistently across participants. These contrasted with results from execution-related brain activity; a performed sequence was successfully predicted from the activities in the broad cortical sensory-motor network, including bilateral motor, parietal and ipsilateral somatosensory cortices. Our study supports the hypothesis that temporary well-organized sequences of movements are represented as a set in the brain, and that preparatory activity in higher-order motor regions represents information about upcoming motor actions. This article is protected by copyright. All rights reserved.

PMID: 26342210 [PubMed - as supplied by publisher]