Brain–Computer Interfaces - Index of

218 D.M. Taylor and M.E. Stetner
followed by a positive peak, and the amplitude of these peaks can vary with movement
direction. Work by Merhing and colleagues suggest that intended targets can
be estimated just as well from these LFP amplitudes as from the firing rates of
individual neurons in monkeys performing a center-out task [26].
Information useful for BCI control has been extracted in many forms from intracortical
microelectrodes (firing rates, spike synchronization, local field potentials,
etc.). All forms can be recorded from the same intracortical electrodes, and, if
you have the computational power, all can be analyzed and used simultaneously.
Complex detailed information about our activities and behavior can be gleaned
from the signals recorded on these tiny microelectrode arrays. Current studies with
intracortical electrodes show much promise for both rapid target selection and generation
of signals that can be used to control full arm and hand movements. Because
intracortical electrodes are so small, many hundreds to even thousands of microelectrodes
can potentially be implanted in the cortex at one time. We have only begun to
scratch the surface of the complex information that will likely be decoded and used
for BCI control from intracortical electrodes in the future.
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