Comment on 'fast attainment of computer cursor control with noninvasively acquired brain signals'

In a recent paper by Bradberry, Gentili and Contreras-Vidal published in Journal of Neural Engineering (2011, 8 036010), an interesting method for the control of a two-dimensional mouse cursor was proposed, which apparently attained excellent control and good speed with relatively simple techniques. We believe some of the results in the paper have been misinterpreted due to a failure in appreciating the self-fulfilling nature of the success criteria adopted. In this comment, we explain the nature of the problem and attempt to assess its influence on the results reported in the aforementioned paper.