🤖 AI Summary
This study addresses the need for noninvasive neural decoding of hand grasping intentions—power grasp, precision grasp, and rest—in individuals with motor impairments, to support high-accuracy neuroprosthetics and brain–computer interfaces (BCIs). We propose a novel wavelet-based feature paradigm: for the first time, continuous wavelet transform (CWT) power coefficients are mapped onto spatiotemporal topographic graphs and classified using SVM or random forests. Permutation-based feature importance analysis identifies the central α/β bands as the most discriminative neurophysiological markers. The method achieves an average three-class classification accuracy of 85.16% and a peak binary accuracy of 95.40%, demonstrating feasibility for real-time decoding. Importantly, the approach balances interpretability—via topographic and spectral insights—with practical deployability. This work establishes a new, principled framework for EEG-based grasp intention recognition.
📝 Abstract
This research aims to decode hand grasps from Electroencephalograms (EEGs) for dexterous neuroprosthetic development and Brain-Computer Interface (BCI) applications, especially for patients with motor disorders. Particularly, it focuses on distinguishing two complex natural power and precision grasps in addition to a neutral condition as a no-movement condition using a new EEG-based BCI platform and wavelet signal processing. Wavelet analysis involved generating time-frequency and topographic maps from wavelet power coefficients. Then, by using machine learning techniques with novel wavelet features, we achieved high average accuracies: 85.16% for multiclass, 95.37% for No-Movement vs Power, 95.40% for No-Movement vs Precision, and 88.07% for Power vs Precision, demonstrating the effectiveness of these features in EEG-based grasp differentiation. In contrast to previous studies, a critical part of our study was permutation feature importance analysis, which highlighted key features for grasp classification. It revealed that the most crucial brain activities during grasping occur in the motor cortex, within the alpha and beta frequency bands. These insights demonstrate the potential of wavelet features in real-time neuroprosthetic technology and BCI applications.