A Patient Has an Injury to the Optic Nerves, Such

Multiple Choice

A patient has an injury to the optic nerves, such that the branches of each optic nerve that normally cross to the opposite side of the brain at the optic chiasm are severed. The remaining branches, which do not cross to the other side of the brain, are intact. Which of the following best describes the effect of this injury on his vision?

A) The patient can now see only by using his right eye; his left eye is functionally blind.
B) Only information from the left visual field can enter the patient's brain for processing.
C) Only the signal for half the visual field of each eye is processed by the brain.
D) The patient's brain now receives visual information only from the medial half of each retina.