Single-trial prediction of reaction time variability from MEG brain activity.

Ryu Ohata,Hiroshi Imamizu,Kenji Ogawa

doi:10.1038/srep27416

Abstract

Neural activity prior to movement onset contains essential information for predictive assistance for humans using brain-machine-interfaces (BMIs). Even though previous studies successfully predicted different goals for upcoming movements, it is unclear whether non-invasive recording signals contain the information to predict trial-by-trial behavioral variability under the same movement. In this paper, we examined the predictability of subsequent short or long reaction times (RTs) from magnetoencephalography (MEG) signals in a delayed-reach task. The difference in RTs was classified significantly above chance from 550 ms before the go-signal onset using the cortical currents in the premotor cortex. Significantly above-chance classification was performed in the lateral prefrontal and the right inferior parietal cortices at the late stage of the delay period. Thus, inter-trial variability in RTs is predictable information. Our study provides a proof-of-concept of the future development of non-invasive BMIs to prevent delayed movements.

Highlights

A delayed movement is inevitable regardless how we strive to make a fast reaction
We obtained significant accuracy in the left superior temporal area (Temporal_Sup_L) at the early stage of the delay period, which was between −725 and −625 ms. These results indicate that various regions other than those related to motor planning/preparation influence trial-by-trial variable reaction times (RTs)
Neurophysiological studies suggest that neural activity during the preparatory period is a crucial source of behavioral variability[10,26,27]

Summary

Introduction

A delayed movement is inevitable regardless how we strive to make a fast reaction. predicting trial-by-trial variability in subsequent RTs plays a crucial role in preventing accidents due to the delayed reactions of operators. A number of previous studies have suggested that pre-movement activities in the premotor (PM), the primary motor (M1), the posterior parietal cortex (PPC) and the supplementary motor area (SMA) are involved in motor planning and the preparation for both stimulus-triggered and voluntary movements[6,7,8,9]. These areas probably include critical information for predictions, it is unknown whether non-invasive methods can detect subtle differences in neural activity among trials with variable RTs. An electrophysiological study in non-human primates showed the possibility of predicting inter-trial RT variability before movement onset[10].

Methods

Results

Conclusion