Which of the following is an early manifestation of amyotrophic lateral sclerosis (ALS)?

• A. Tremor in the fingers
• B. Visual disturbances
• C. Hearing loss
• D. Weakness of the distal extremities

Answer: (D)

ALS starts with degeneration of motor neurons, so the first changes are in muscles you control voluntarily rather than in sensory or special senses. The hands and feet—the distal muscles—are typically the earliest affected, leading to weakness that makes fine motor tasks like gripping, buttoning, writing, or walking more difficult. Visual disturbances and hearing loss aren’t caused by motor neuron degeneration and aren’t expected in early ALS, and while some twitching can occur, a plain, early sign is the notable distal weakness. As the disease advances, weakness spreads to other muscles and upper motor neuron signs like increased tone and reflexes appear alongside continued muscle atrophy.