  A major objective of Brain-Computer interfaces (BCI) is to restore
communication and control in patients with severe motor impairments, like
people with Locked-in syndrome. These patients are left only with limited eye
and eyelid movements. However, they do not benefit from efficient BCI
solutions, yet. Different signals can be used as commands for non-invasive BCI:
mu and beta rhythm desynchronization, evoked potentials and slow cortical
potentials. Whatever the signal, clinical studies show a dramatic loss of
performance in severely impaired patients compared to healthy subjects.
Interestingly, the control principle is always the same, namely the replacement
of an impossible (overt) movement by a (covert) attentional command. Drawing
from the premotor theory of attention, from neuroimaging findings about the
functional anatomy of spatial attention, from clinical observations and from
recent computational accounts of attention for both action and perception, we
explore the hypothesis that these patients undergo negative plasticity that
extends their impairment from overt to covert attentional processes.
