Which disease is defined as a degenerative disorder of motor neurons in the spinal cord and brainstem?

• A. Headache
• B. Epilepsy
• C. Multiple Sclerosis
• D. Amyotrophic Lateral Sclerosis

Answer: (D)

Progressive degeneration of motor neurons in the spinal cord and brainstem is being described. Amyotrophic Lateral Sclerosis fits this exactly, as it targets the neurons that control voluntary muscles—both in the spinal cord (anterior horn cells) and in the brainstem motor nuclei—leading to muscle weakness and wasting. As these motor neurons deteriorate, you’ll see signs from both upper and lower motor neurons: spasticity and brisk reflexes from the upper motor neuron side, and muscle fasciculations and atrophy from the lower motor neuron side. Other options don’t match this pattern: headaches are nonspecific symptoms; epilepsy is a seizure disorder; multiple sclerosis is a demyelinating autoimmune disease of the CNS, not a primary degeneration of motor neurons in those regions.