Why build an integrated EEG-NIRS? About the advantages of hybrid bio-acquisition hardware

Objective: In medical applications, neuroscience and brain-computer interface research, bimodal acquisition of brain activity using Electroencephalography (EEG) and functional Near Infrared Spectroscopy (fNIRS) is at the moment achieved by combining separate commercial devices. We have investigated quantitatively whether dedicated hybrid systems exhibit more advantageous properties. Methods: We studied intermodality electrical crosstalk and timing jitter in two separate and one hybrid EEG-NIRS acquisition device. Results: Analysis revealed significantly higher impact of electrical NIRS current crosstalk into the EEG inputs and timing jitters between EEG-NIRS markers in separate devices compared to the hybrid system. Conclusion: The results support hybrid acquisition systems to be advantageous in setups that require high performance in timing and signal quality.