Ultrasound-modulated EEG: new decoding algorithm tested on 10 volunteers, 0.79 mm resolution
A decoding method for ultrasound-modulated EEG kept correlations of 0.84–0.90 across weak to over modulation in simulations, phantoms and 10 volunteers.

Researchers described a decoding algorithm for ultrasound-modulated electroencephalography (USMEEG) in Science Advances. The method is based on the ultrasound pulse repetition frequency. It was tested in numerical simulations, in phantoms and on human steady-state visual evoked potential signals from 10 volunteers doi.org
Science Advancesdoi.orgOpen source ↗. The focused ultrasound phased array achieved an encoding spatial resolution of 0.79 millimeters
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Science Advancesdoi.orgOpen source ↗.
USMEEG combines millimeter-level spatial resolution with millisecond-level temporal resolution. According to the authors, in extremely complex scenarios acoustoelectric signal coupling that is too strong or too weak severely distorts the decoded signals doi.org
Science Advancesdoi.orgOpen source ↗. To describe such cases, they introduced the acoustoelectric modulation ratio (AMR), which quantifies different modulation scenarios
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Science Advancesdoi.orgOpen source ↗.
The algorithm was compared with four traditional methods and, the authors report, significantly outperformed them. Average decoding correlations were 0.84 under weak modulation (0 < AMR ≤ 0.6), 0.90 under moderate modulation (0.6 < AMR ≤ 1) and 0.89 under over modulation (AMR > 1) doi.org
Science Advancesdoi.orgOpen source ↗. The authors state that the technique expands USMEEG applications and provides a technical foundation for high-performance noninvasive brain-computer interfaces
doi.org
Science Advancesdoi.orgOpen source ↗.



