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bioRxiv · 10.1101/2021.12.14.453704

Identifying Uncertainty States during Wayfinding in Indoor Environments: An EEG Classification Study

Abstract

The researchers used a machine-learning classification approach to better understand neurological features associated with periods of wayfinding uncertainty. The participants (n=30) were asked to complete wayfinding tasks of varying difficulty in a virtual reality (VR) hospital environment. Time segments when participants experienced navigational uncertainty were first identified using a combination of objective measurements (frequency of inputs into the VR controller) and behavioral annotations from two independent observers. Uncertainty time-segments during navigation were ranked on a scale from 1 (low) to 5 (high). The machine-learning model, a random forest classifier implemented using scikit-learn in Python, was used to evaluate common spatial patterns of EEG spectral power across the theta, alpha, and beta bands associated with the researcher-identified uncertainty states. The overall predictive power of the resulting model was 0.70 in terms of the area under the Receiver Operating Characteristics curve (ROC-AUC). These findings indicate that EEG data can potentially be used as a metric for identifying navigational uncertainty states, which may provide greater rigor and efficiency in studies of human responses to architectural design variables and wayfinding cues.

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BibTeXRIS

Zhu, B., Cruz-Garza, J. G., Shoaran, M., Kalantari, S.. 2021-12-16. Identifying Uncertainty States during Wayfinding in Indoor Environments: An EEG Classification Study. https://doi.org/10.1101/2021.12.14.453704

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