Hardware-enabled low latency rhythmic brain state tracking for brain stimulation applications

Abstract

Objective: Upcoming neuroscientific research will require bidirectional and context dependent interaction with nervous tissue. To facilitate the future neuroscientific discoveries we have created HarPULL, a genuinely real-time system for tracking oscillatory brain state. Approach: The HarPULL technology ensures reliable, accurate and affordable real-time phase and amplitude tracking based on the state-space estimation framework operationalized by Kalman filtering. To avoid data transfer delays and to obtain a truly real-time system the algorithm is implemented on the computational core of an EEG amplifier controlled by a real-time operating system. Systems performance is tested with simulated and real data both online and offline and within a real-time state dependent TMS using a phantom and human subjects. Main results: We show that taking into account the 1/f nature of the brain noise and the use of the …