A degenerative disorder affecting upper MOTOR NEURONS in the brain and lower motor neurons in the brain stem and SPINAL CORD. Disease onset is usually after the age of 50 and the process is usually fatal within 3 to 6 years. Clinical manifestations include progressive weakness, atrophy, FASCICULATION, hyperreflexia, DYSARTHRIA, dysphagia, and eventual paralysis of respiratory function. Pathologic features include the replacement of motor neurons with fibrous ASTROCYTES and atrophy of anterior SPINAL NERVE ROOTS and corticospinal tracts. (From Adams et al., Principles of Neurology, 6th ed, pp1089-94)

A neurodegenerative disease characterized by progressive muscular paralysis reflecting degeneration of motor neurons in the primary motor cortex, corticospinal tracts, brainstem and spinal cord.

A neurodegenerative disorder characterized by progressive degeneration of the motor neurons of the central nervous system. It results in weakness and atrophy of the muscles which leads to an inability to initiate and control voluntary movements.

Amyotrophic lateral sclerosis (ALS) is a nervous system disease that attacks nerve cells called neurons in your brain and spinal cord. These neurons transmit messages from your brain and spinal cord to your voluntary muscles - the ones you can control, like in your arms and legs. At first, this causes mild muscle problems. Some people notice: Trouble walking or running; Trouble writing; Speech problems. Eventually, you lose your strength and cannot move. When muscles in your chest fail, you cannot breathe. A breathing machine can help, but most people with ALS die from respiratory failure. The disease usually strikes between age 40 and 60. More men than women get it. No one knows what causes ALS. It can run in families, but usually it strikes at random. There is no cure. Medicines can relieve symptoms and, sometimes, prolong survival. NIH: National Institute of Neurological Disorders and Stroke

Progressive degeneration of the neurons that give rise to the corticospinal tract and of the motor cells of the brain stem and spinal cord, resulting in a deficit of upper and lower motor neurons.

Amyotrophic lateral sclerosis (ALS) is the most common degenerative disease of the motor neuron system. The disorder is named for its underlying pathophysiology, with �amyotrophy� referring to the atrophy of muscle fibers, which are denervated as their corresponding anterior horn cells degenerate.

Amyotrophic lateral sclerosis (a-my-o-TROE-fik LAT-ur-ul skluh-ROE-sis), or ALS, is a progressive nervous system disease that affects nerve cells in the brain and spinal cord, causing loss of muscle control.

Amyotrophic lateral sclerosis (ALS), also referred to as "Lou Gehrig's disease," is a progressive motor neuron disease which leads to problems with muscle control and movement. There are various types of ALS that are distinguished by symptoms and, in some cases, genetic cause. Early symptoms may include muscle twitching, cramping,...

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder, characterized by progressive muscle weakness that can start in limb, axial, bulbar, or respiratory muscles and then generalizes relentlessly, causing progressive disability and ultimately death, usually from respiratory failure.

Amyotrophic lateral sclerosis (ALS), degenerative neurological disorder that causes muscle atrophy and paralysis. The disease usually occurs after age 40; it affects men more often than women. ALS is frequently called Lou Gehrig disease in memory of the famous baseball player Lou Gehrig, who died...