The investigators will evaluate whether transauricular vagus nerve stimulation (taVNS) delivered during extensor movements executed on a robotic device will alter the clinical measurement of upper limb motor performance in 45 patients with chronic stroke.~Patients will engage the robot first with their unaffected limb. This practice will ensure understanding and serve to activate the hemisphere ipsilateral to the impaired limb. Patients are likely to perform this activity quickly, there will not be any taVNS during this part of the procedure. Patients will then wear the taVNS device on the left ear for the duration of the subsequent phase of the robotic training. During this phase the patient will engage the robotic device with the affected limb and complete the protocol and the stimulation or sham stimulation will occur with every extensor movement.
To determine whether treatment with transauricular vagus nerve stimulation (taVNS) during the training of an affected upper limb of a patient with chronic stroke on a robotic motor task alters the motor impairment.