Having no movement whatsoever I control an environmental system (called "Possum") solely by whistling into a microphone.

CNN: 'I lived in an iron lung for seven years'

Mr. Dean says the head movement directly impacts the vestibular system, causing the complete balance control scheme to work and adapt.

WSJ: For the Love of Surfing and Wine Country

For one thing, such devices allow the patient to sense the movement of the arm through a system of cables which are used to control the device, usually by attaching them to the opposite shoulder.

ECONOMIST: Rewiring nerves