An electronic neuromorphic system for real-time detection of High Frequency Oscillations (HFOs) in intracranial EEG

TL;DR

This paper introduces a novel neuromorphic chip integrating recording, processing, and detection of High Frequency Oscillations in intracranial EEG, enabling real-time, on-chip epilepsy biomarker detection with promising clinical implications.

Contribution

It presents the first integrated neuromorphic system combining neural recording and spiking neural network processing on a single chip for real-time HFO detection.

Findings

Successfully detected HFOs in intracranial EEG data from epilepsy patients.

Achieved high accuracy, specificity, and sensitivity in predicting surgical outcomes.

Demonstrated low power consumption suitable for clinical applications.

Abstract

In this work, we present a neuromorphic system that combines for the first time a neural recording headstage with a signal-to-spike conversion circuit and a multi-core spiking neural network (SNN) architecture on the same die for recording, processing, and detecting High Frequency Oscillations (HFO), which are biomarkers for the epileptogenic zone. The device was fabricated using a standard 0.18$\mu$m CMOS technology node and has a total area of 99mm$^{2}$. We demonstrate its application to HFO detection in the iEEG recorded from 9 patients with temporal lobe epilepsy who subsequently underwent epilepsy surgery. The total average power consumption of the chip during the detection task was 614.3$\mu$W. We show how the neuromorphic system can reliably detect HFOs: the system predicts postsurgical seizure outcome with state-of-the-art accuracy, specificity and sensitivity (78%, 100%, and 33% respectively). This is the first feasibility study towards identifying relevant features in intracranial human data in real-time, on-chip, using event-based processors and spiking neural networks. By providing "neuromorphic intelligence" to neural recording circuits the approach proposed will pave the way for the development of systems that can detect HFO areas directly in the operation room and improve the seizure outcome of epilepsy surgery.