Which rare progressive disorder involves gradual deterioration of the motor neurons in the body?

• A. Motor Neurone Disease
• B. Parkinson's Disease
• C. Cerebral Palsy
• D. Multiple Sclerosis

Answer: (A)

Progressive loss of motor neurons causing muscle weakness is the hallmark of motor neuron disease. In this condition, the nerve cells that control voluntary muscles deteriorate over time, leading to a gradual decline in movement, speech, swallowing, and eventually breathing as it progresses. It is rare and follows a progressive course, meaning symptoms worsen over months to years. Amyotrophic lateral sclerosis (ALS) is the best-known form, affecting both upper and lower motor neurons.

Parkinson's disease results from loss of dopamine-producing neurons in a different brain region (the basal ganglia), causing tremor, rigidity, and slowness but not primarily motor neuron degeneration. Cerebral palsy stems from brain injury early in life and is typically non-progressive. Multiple sclerosis involves autoimmune damage to the myelin sheath of nerves, with fluctuating or progressive neurological symptoms, rather than degeneration of motor neurons themselves.

So the described condition is motor neuron disease.