Temporal lobe lesions typically cause which type of visual field defect?

Temporal lobe lesions typically cause which type of visual field defect?

• A. Superior VF defects
• B. Inferior VF defects
• C. Central scotoma
• D. Quadrantanopia

Answer: (A)

Damage to the temporal lobe affects Meyer's loop, a part of the optic radiations that carries information about the opposite side’s upper visual field. When this pathway is disrupted, you lose the upper portion of the field in the contralateral eye, producing a contralateral superior quadrantanopia (the “pie in the sky” defect). Central scotomas come from macular or occipital cortex involvement, not from Meyer's loop, and inferior visual field defects are more typical of parietal lobe involvement. So the characteristic pattern with temporal lobe lesions is a superior quadrantanopia, a quadrant-based defect in the upper visual field.

Damage to the temporal lobe affects Meyer's loop, a part of the optic radiations that carries information about the opposite side’s upper visual field. When this pathway is disrupted, you lose the upper portion of the field in the contralateral eye, producing a contralateral superior quadrantanopia (the “pie in the sky” defect). Central scotomas come from macular or occipital cortex involvement, not from Meyer's loop, and inferior visual field defects are more typical of parietal lobe involvement. So the characteristic pattern with temporal lobe lesions is a superior quadrantanopia, a quadrant-based defect in the upper visual field.