Measuring the functional connectome "on-the-fly": towards a new control signal for fMRI-based brain-computer interfaces
This work addresses a bottleneck in real-time fMRI applications, enabling multi-region connectivity tracking for potential clinical and training uses, though it is incremental as it builds on existing algorithms.
The authors tackled the challenge of estimating dynamic functional connectivity networks in real-time for fMRI-based brain-computer interfaces, proposing a novel methodology that adapts the SINGLE algorithm to track changes quickly and accurately, showing it can detect significant task-related network changes in motor task and virtual environment data.
There has been an explosion of interest in functional Magnetic Resonance Imaging (MRI) during the past two decades. Naturally, this has been accompanied by many major advances in the understanding of the human connectome. These advances have served to pose novel challenges as well as open new avenues for research. One of the most promising and exciting of such avenues is the study of functional MRI in real-time. Such studies have recently gained momentum and have been applied in a wide variety of settings; ranging from training of healthy subjects to self-regulate neuronal activity to being suggested as potential treatments for clinical populations. To date, the vast majority of these studies have focused on a single region at a time. This is due in part to the many challenges faced when estimating dynamic functional connectivity networks in real-time. In this work we propose a novel methodology with which to accurately track changes in functional connectivity networks in real-time. We adapt the recently proposed SINGLE algorithm for estimating sparse and temporally homo- geneous dynamic networks to be applicable in real-time. The proposed method is applied to motor task data from the Human Connectome Project as well as to real-time data ob- tained while exploring a virtual environment. We show that the algorithm is able to estimate significant task-related changes in network structure quickly enough to be useful in future brain-computer interface applications.