Amyotrofic lateral sclerosis is the name attributed to a particular form of progressive degeneration of the motor neurons which are responsible for voluntar movements of the body. Amyotrofic lateral sclerosis progressively hinders muscular activity and over time, as the diseas progresses, causes extreme physical disability. There are no known causes to Amyotrofic lateral sclerosis, although many experimentations have led scientists to believe that specific cellular defects caused by genetic mutations can be related to the onset of Amyotrofic lateral sclerosis. Amyotrofic lateral sclerosys hit approximately one individual out of 100.000, mainly from 40 to 60 years of age and is more frequent between men than women. The first symptoms related to Amyotrofic lateral sclerosis is muscular atrophy caused by their reduced use: the motor neurons fail to send electric signals to peripheral nerves and the muscles progrssively wear off. The general perception is that of overall weakness and progressive difficulty in executing simple daily tasks connected to the muscles initially involved in the degeneration process. Amyotrofic lateral sclerosis will eventually spread to the whole body: the subject will then be unable to walk, stand, lift or manipulate objects and will be forced to bed. When difficulty in speaking, chewing and swallowing is also present, it will degenerate into complete inability to speak and eat normally. Finally, in the later stages of the diseas, the involuntary muscles preposed to breathing start to be affected and the person is forced to resort to articial breathing equipment in order to survive. Amyotrofic lateral sclerosis commonly leads to death due to breathing failure. Amyotrofic lateral sclerosis does not affect cognitive capabilities, and the person will be fully aware of his own physical degeneration. When speech impairment is involved, communication also becomes an issue, as the person undestands his situation but is not able to get in touch with anyone. Specific assistive devices can therefore be of great use to grant autonomy in communication and computer use, takeing advantage of the head and eye movements, which are the last muscles on which voluntary control is retained.
