title: Performance assessment of a brain-computer interface driven hand orthosis.
abstract: Stroke survivors are typically affected by hand motor impairment. Despite intensive rehabilitation and spontaneous recovery, improvements typically plateau a year after a stroke. Therefore, novel approaches capable of restoring or augmenting lost motor behaviors are needed. Brain-computer interfaces (BCIs) may offer one such approach by using neurophysiological activity underlying hand movements to control an upper extremity orthosis. To test the performance of such a system, we developed an electroencephalogram-based BCI controlled electrically actuated hand orthosis. Six able-bodied participants voluntarily grasped/relaxed one hand to elicit BCI-mediated closing/opening of the orthosis mounted on the opposite hand. Following a short training/calibration procedure, participants demonstrated real-time, online control of the orthosis by following computer cues. Their performances resulted in an average of 1.15 (standard deviation: 0.85) false alarms and 0.22 (0.36) omissions per minute. Analysis of signals from electrogoniometers mounted on both hands revealed an average correlation between voluntary and BCI-mediated movements of 0.58 (0.13), with all but one online performance being statistically significant. This suggests that a BCI driven hand orthosis is feasible, and therefore should be tested in stroke individuals with hand weakness. If proven viable, this technology may provide a novel approach to the neuro-rehabilitation of hand function after stroke.
authors.affiliation: Department of Biomedical Engineering, University of California, Irvine (UCI), Irvine, CA, USA.
authors.forename: Christine E
authors.initials: CE
authors.lastname: King
authors.forename: Kunal R
authors.initials: KR
authors.lastname: Dave
authors.forename: Po T
authors.initials: PT
authors.lastname: Wang
authors.forename: Masato
authors.initials: M
authors.lastname: Mizuta
authors.forename: David J
authors.initials: DJ
authors.lastname: Reinkensmeyer
authors.forename: An H
authors.initials: AH
authors.lastname: Do
authors.forename: Shunji
authors.initials: S
authors.lastname: Moromugi
authors.forename: Zoran
authors.initials: Z
authors.lastname: Nenadic
mesh_terms: D000328:Adult; D062207:Brain-Computer Interfaces; D002138:Calibration; D004566:Electrodes; D004569:Electroencephalography / Q000295:instrumentation; D005260:Female; D006225:Hand / Q000502:physiology*; D006801:Humans; D008297:Male; D009989:Orthotic Devices; D055815:Young Adult