Final answer:
The left optic nerve receives visual signals from the right visual field of both eyes. Damage to the left optic nerve results in loss of vision in the right visual field of both eyes due to the interruption of signal transmission to the brain.
Step-by-step explanation:
The left optic nerve receives visual signals from the right visual field of both eyes. This is because the axons from the lateral (temporal) retina of the left eye and the medial (nasal) retina of the right eye combine at the optic chiasm to form the left optic tract, which then leads to the left side of the brain. If the left optic nerve was cut or damaged, it would result in loss of vision in the right visual field of both eyes, a condition known as hemianopia. This is because the damaged nerve would not be able to transmit visual information from that side of the visual fields to the brain for processing.
In cases where visual field deficits are detected, such as loss of peripheral vision, it suggests damage along the length of the optic pathway. For instance, a pituitary tumor pressing against the optic chiasm can cause loss of peripheral vision by interrupting the transmission of visual signals from the medial retinas, which carry information from the peripheral visual fields.