Mussa-Ivaldi connection of the mobile robot to the lamprey brainstem is illustrated below. Signals from the optical sensors of the robot were encoded by the brain machine interface (BMI) into electrical stimulations, with the frequency of the stimulations depending on the light intensity.
These stimulations were delivered by electrodes to the right and left vestibular pathways in the lamprey brain. The stimuli are specifically delivered to the axons of the intermediate and posterior octavomotor nuclei (nOMI and nOMP), and recording electrodes record responses to the stimuli which are subsequently decoded by the BMI. During decoding, first the recording artifacts are removed, then the population spikes (bursts of activity) are detected and an average firing rate is computed. This firing rate is translated into a command to the corresponding wheel of the robot, which the angular velocity of the wheel set to be proportional to the average firing rate.
Researchers believe that in the future robotic arms and legs will be wired directly into, and controlled by, the brains of individuals whose own limbs have been lost because of accident or disease. Recent studies by Nudo and co-workers have provided preliminary evidence that the combination of behavioral training and electrical stimulation of areas surrounding a cerebrovascular accident can lead to a significant acceleration of functional recovery. If results such as these find further support, one could envisage a future scenario in which the closed-loop interaction between a patient's brain and an external device will be used to facilitate the reorganization of neural circuits that is necessary for reestablishing normal movement patterns.