Vagus Nerve Stimulation has been used for a stroke treatment trial
The trial aims to find a treatment specifically for stroke patients with arm and hand weakness.
The implanted device sends electrical signals over the damaged part of the brain to a healthy area.
An implanted device sends electrical pulses via the vagus nerve, stimulating it to bypass damaged areas.
Vagus Nerve Stimulation has already been used to treat people with epilepsy and depression.
Patients brain re-learn how to use the stroke-affected limb with continuing physiotherapy.
A patient, who is on trial, can now use his left hand which had been "dead" since his stroke.
The trial involves patients in the UK and USA and is due to end next year.