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PubMed · 15687805

Changing the P300 brain computer interface.

Jessica D Bayliss·Samuel A Inverso·Aleksey Tentler
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Abstract

Brain-computer interfaces (BCIs) are now feasible for use as an alternative control option for those with severe motor impairments. The P300 component of the evoked potential has proven useful as a control signal. Individuals do not need to be trained to produce the signal, and it is fairly stable and has a large evoked potential. Even with recent signal classification advances, on-line experiments with P300-based BCIs remain far from perfect. We present two potential methods for improving control accuracy. Experimental results in an evoked potential BCI, used to control items in a virtual apartment, show a reduced response exists when items are accidentally controlled. The presence of a P300-like signal in response to goal items means that it can be used for automatic error correction. Preliminary results from an interface experiment using three different button configurations for a yes/no BCI task show that the configuration of buttons may affect on-line signal classification. These results will be discussed in light of the special considerations needed when working with an amyotrophic lateral sclerosis (ALS) patient.

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BrainComputersEvent-Related Potentials, P300HumansModels, TheoreticalUser-Computer InterfaceJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Jessica D Bayliss, Samuel A Inverso, Aleksey Tentler. 2004. Changing the P300 brain computer interface.. https://doi.org/10.1089/cpb.2004.7.694

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