Final answer:
Bilateral hemianopia resulting from a bilateral occipital lobe lesion leads to loss of lateral peripheral vision without affecting superior and inferior peripheral vision due to damage to visual pathways, often from a growth compressing the optic chiasm.
Step-by-step explanation:
A bilateral occipital lobe lesion often presents as bilateral hemianopia, which involves the loss of lateral peripheral vision but not the loss of superior and inferior peripheral fields. This visual field deficit can be confused with but is distinct from "tunnel vision" where central vision is preserved while the peripheral vision is uniformly diminished. Unlike tunnel vision, bilateral hemianopia results from visual pathway disruption such as when a pituitary gland growth compresses the optic chiasm, affecting signal transmission to the occipital lobe where visual processing occurs.
The occipital lobe is essential for seeing, recognizing, and identifying the visual world, and when both lobes are damaged, the result can significantly impact a patient's ability to navigate their environment. Other associated symptoms might include diplopia or problems with higher-order visual processing such as prosopagnosia, depending on the extent of the occipital and associated neural structure damage.