Of or pertaining to James the First, of England, or of his reign or times; especially, pertaining to a style of architecture and decoration popular in the time of James I.; as, Jacobean writers. Etymology: From L. Jacobus James.
ALS is a progressive, degenerative disease of the nervous system. It is one of a group of diseases, called motor neuron diseases (MND), in which specialized nerve cells that control movement of the voluntary muscles gradually cease functioning and die. Fasciculation is a sign of muscle irritability, as the normal action of the lower motor neuron on the muscle is impaired. 2  The sole involvement of lower motor neurons can be seen in a form of ALS called progressive muscular atrophy.
Causes of muscle atrophy. Unused muscles can waste away if you are not active. Even after it begins, this type of atrophy can often be reversed with exercise and improved nutrition. Muscle atrophy can also happen if you are bedridden or unable to move certain body parts due to a medical condition. Astronauts, for example, can also experience some muscle atrophy after a few days of weightlessness. Other causes for muscle atrophy include: lack of physical activity for an extended period of time.