At the University of Tübingen in Germany, neurobiologist Andrea Kübler works with a 49-year-old patient whom she identifies only as H.S. Like many of Kübler’s patients, H.S. suffers from amyotrophic lateral sclerosis (ALS), a degenerative disease that slowly breaks down the nerve cells necessary for motion. The disease has paralyzed H.S., stripping him of the motor functions that most people take for granted: sitting up, eating, and even breathing.
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H.S. was diagnosed with ALS 14 years ago, and a permanent ventilator has done his breathing for him since 1993. From then until recently, H.S. could converse with Kübler and his caregivers only by blinking his eyes.