Man with motor neurone disease walking, Muybridge motion study, 1880s. Series of photographs showing a man with motor neurone disease, or amyotrophic lateral sclerosis, (ALS) walking. The disease causes the death of neurons (nerve cells) controlling voluntary muscles. Most patients eventually lose the ability to walk, use their hands, speak, swallow, and breathe. These photographs were obtained by English photographer Eadweard J. Muybridge (1830-1904) in his pioneering work documenting the motion of humans and animals. Between 1883 and 1886, Muybridge made more than 100,000 images using his ground-breaking stop-motion photography techniques. In 1885 he partnered with Francis Dercum, chief of the Hospital of the University of Pennsylvania's Dispensary for Nervous Diseases to study the movement of neurological patients. The results were published in 'Animal Locomotion' (1887). This study was published in Volume VIII: Abnormal Movements. Males and Females (nude and semi-nude).