jdb[at]cs[dot]rit[dot]edu

Abstract

sinverso[at]gmail[dot]com Recent advances in signal processing have made brain-computer interfaces (BCIs) feasible for use as an alternative control option for those with severe motor impairments. It is possible to increase the accuracy of a BCI system by requiring users to make multiple choices to control a single item, but this comes at a cost of reduced system speed. We present experimental results from an evoked potential BCI used to control items in a virtual apartment and show the existence of the evoked potential P3 component in responses to successfully controlled goal items. A reduced response exists when items are accidentally controlled. The presence of the P3 component in responses to goal items means that it can be used for automatic error correction. Off-line experiments have been run and with a theoretical mean improvement in recognition from 78 % to 85%, we show a statistically significant improvement (p < 0.004, Wilcoxen test, two-tailed) in accuracy of 3 % using the variable averaging algorithm. Since the error correction technique depends on responses to controlled items in a particular experimental paradigm rather than the control of the items themselves, it may be possible to use this response in non-evoked potential BCI systems. Future work is discussed in this context.