De novo brain-computer interfacing deforms manifold of populational neural activity patterns in human cerebral cortex

Iwama, S.; Yichi, Z.; Ushiba, J.

doi:10.1101/2021.06.28.450263

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bioRxiv · 10.1101/2021.06.28.450263

De novo brain-computer interfacing deforms manifold of populational neural activity patterns in human cerebral cortex

Iwama, S.·Yichi, Z.·Ushiba, J.

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Abstract

Human brains are capable of modulating innate activities to adapt to novel environmental stimuli; for sensorimotor cortices (SM1) this means acquisition of a rich repertoire of motor behaviors. We investigated the adaptability of human SM1 motor control by analyzing net neural population activity during the learning of brain-computer interface (BCI) operations. We found systematic interactions between the neural manifold of cortical population activities and BCI classifiers; the neural manifold was stretched by rescaling motor-related features of electroencephalograms with model-based fixed classifiers, but not with adaptive classifiers that were constantly recalibrated to user activity. Moreover, operation of a BCI based on a de novo classifier with a fixed decision boundary based on biologically unnatural features, deformed the neural manifold to be orthogonal to the boundary. These principles of neural adaptation at a macroscopic level may underlie the ability of humans to learn wide-ranging behavioral repertoires and adapt to novel environments. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=64 SRC="FIGDIR/small/450263v1_ufig1.gif" ALT="Figure 1"> View larger version (16K): org.highwire.dtl.DTLVardef@12a66c3org.highwire.dtl.DTLVardef@c090e8org.highwire.dtl.DTLVardef@698f87org.highwire.dtl.DTLVardef@4e135c_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Iwama, S., Yichi, Z., Ushiba, J.. 2021-06-30. De novo brain-computer interfacing deforms manifold of populational neural activity patterns in human cerebral cortex. https://doi.org/10.1101/2021.06.28.450263

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