The term âcatapultâ is used to define a very wide variety of large machines for hurling projectiles and some of the more common variations include the trebuchet, which is a catapult that uses gravity and a seesaw effect to hurl its projectile.
A demyelinating disease is any condition that results in damage to the protective covering (myelin sheath) that surrounds nerve fibers in your brain and spinal cord.
Causes of Demyelination. Inflammation is the most common cause of myelin damage. Other causes include: 1  inflammation. 2  infection with certain viruses. 3  metabolic problems.4  loss of oxygen.5  physical compression.S is a chronic disease where demyelination occurs in the white matter of the brain and in the spinal cord. In areas where myelin is under attack by the immune system, lesions or âplaquesâ form. These plaques are scar tissue.