Stockwell Coherence and Its Application in Studying Motor Cortices under the Multi-Source Interference Task

Coherence function plays an important role in measuring brain functional connectivity. In this paper, we extend the definition of coherence function from the classic Fourier domain to the time-frequency plane using the Stockwell transform. This extension has advantages over other existing time-varying coherence functions in terms of easy interpretation and fast computation. An application of our approach to an MEG study reveals interesting temporal interaction between contralateral and ipsilateral motor cortices under the multi-source interference task.