Stephen Hawking, a famous physicist, also suffered from amyotrophic lateral sclerosis(ALS). ALS is characteristic in a way that even in the late stages, sensory, bowel and bladder, and cognitive function are preserved. Even if the disease progresses to severe brainstem involvement, ocular movement is usually spared, until the very late stage. Because of brainstem involvement, the victims is unable to talk even though he can understand speeches. ‘The only muscular movement one could have left is perhaps the eyes and the diaphragm’.