Video Transcript
Motor neuron disease is a condition
where the motor neurons of the nervous system are progressively broken down and
damaged over time. Which of these symptoms would you
expect to see in a person with motor neuron disease? (A) An increased tolerance to pain
and heat. (B) A persistent cough and sore
throat. (C) Increased speed of
reflexes. (D) Difficulty moving around and
holding objects. Or (E) a loss of smell and
taste.
The question asks us about motor
neuron disease, a condition that results in the chronic destruction of motor neurons
in the nervous system. The condition gets worse with
time. One of the more common types of
motor neuron disease is amyotrophic lateral sclerosis, or ALS for short. You might have heard that the
famous British physicist Stephen Hawking had this particular disease. Unfortunately, there is no cure for
motor neuron disease, so the illness is terminal.
To determine what symptoms we would
expect with motor neuron disease, we should think about the function of motor
neurons. They are responsible for
transmitting electrical impulses away from the central nervous system to
effectors. Effectors include muscle fibers,
glands, and organs. When motor neurons are functioning
properly, they allow us to respond to sensory stimuli in the environment and perform
both intentional and involuntary movements. However, if the motor neurons are
damaged, these functions become difficult, affecting a person’s mobility.
Early symptoms of motor neuron
disease may be mistaken for clumsiness including tripping, falling, and difficulty
holding objects. Eventually, individuals with motor
neuron disease will be confined to a wheelchair and will have trouble swallowing and
breathing. Returning to our question, we can
see that it asks about the symptoms we would expect to see with motor neuron
disease. Because the disease primarily
affects motor neurons and therefore affects movement, the correct answer is (D). The symptoms we would expect to see
in a person with motor neuron disease are difficulty moving around and holding
objects.
