Question

A 61-year-old business executive with a long history of high blood pressure collapsed while jogging over the lunch hour. His jogging mate quickly contacted a police officer who helped carry the man to a hospital just down the road. At the hospital, an MRI was performed that revealed a blockage of a major cerebral artery and ischemic changes to the portion of the brain supplied by that artery. With quick medical attention, the man was stabilized, and he slowly improved over the next three weeks. The following signs and symptoms did persist, however: - paralysis of the right leg and foot - loss of sensation on the skin of the right leg and foot - when blindfolded, inability to identify a tennis ball placed in the left hand, but ability to name it if placed in the right hand - inability to throw the tennis ball with his left hand, but ability to throw it with his right hand.

QUESTIONS

1. Explain why he is unable to follow the verbal command to throw the tennis ball with his left hand but can do so when asked to with his right hand. In your explanation, be sure to discuss all of the relevant pathways down which nerve impulses must pass in order to follow these commands.

2. Why has he lost sensation in the right leg and foot?

Answer 1

1. The paralysis of the right leg and foot suggests the condition of left sided cerebral stroke. As the leg and foot innervate by the anterior cerebral artery, this is the left ACA stroke.

2. Apraxia is observed where the damage to the area of the brain which coordinates the movements is altered due to the stroke as a result of which the ability of the brain to send the message to throw the ball with the right brain (left hand) is functional, but damage to the left brain (right hand) is reason behind akinesia.