Functional Connectivity during Elbow Movements: Comparison between Motor and Non-motor Task

Abstract

In order to implement cognitive motor brain machine interfaces, the systems must be capable of identifying when a subject wishes to perform a given task. Nowadays, researches normally use parameters as event related synchronism (ERS) and event related desynchronism (ERD) to provide a kind of switch to turn on or off those systems. Directed transfer function (DTF) technique can provide the behaviour of the functional connectivity between brain regions. Some researchers have shown that the change of such parameters may be used to identify when a subject is performing different tasks. In this paper we propose the use of the DTF to identify the changes of functional connectivity between resting state and movement perform for elbow movements (flexion and extension), while a subject is interacting with a robot arm. Results showed that it is possible to identify when subjects are performing motor task and non-motor task by the comparison of their functional connectivity. Another finding is that was possible to distinguish the two elbow movements (flexion and extension) when comparing their functional connectivity. These findings could be used for a better control of a brain machine interface given a subject more freedom on task perform.