Naturalistic hyperscanning with wearable magnetoencephalography

The evolution of human cognitive function is reliant on complex social interactions which form the behavioural foundation of who we are. These social capacities are subject to dramatic change in disease and injury; yet their supporting neural substrates remain poorly understood. Hyperscanning employs functional neuroimaging to simultaneously assess brain activity in two individuals and offers the best means to understand the neural basis of social interaction. However, present technologies are limited, either by poor performance (low spatial/temporal precision) or unnatural scanning environment (claustrophobic scanners, with interactions via video). Here, we solve this problem by developing a new form of hyperscanning using wearable magnetoencephalography (MEG). This approach exploits quantum sensors for MEG signal detection, in combination with high-fidelity magnetic field control - afforded by a novel "matrix coil" system - to enable simultaneous scanning of two freely moving participants. We demonstrate our approach in a somatosensory task and an interactive ball game. Despite large and unpredictable subject motion, sensorimotor brain activity was delineated clearly in space and time, and correlation of the envelope of neuronal oscillations between people was demonstrated. In sum, unlike existing modalities, wearable-MEG combines high fidelity data acquisition and a naturalistic setting, which will facilitate a new generation of hyperscanning.