optic radiations


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Related to optic radiations: Striate cortex, Primary visual cortex

radiations, optic 

That part of the visual pathway which consists of axons arising in the lateral geniculate body and terminating in a fan-shaped manner in the visual area of the occipital lobe. As they emerge from the lateral geniculate body the inferior fibres loop forward in the temporal lobe before swinging back toward the occipital cortex. These fibres form what is called Meyer's loop (or Archambault's loop). They receive impulses from the inferior retinal quadrants (corresponding to the superior aspect of the contralateral visual field) and terminate on the inferior lip of the calcarine fissure. Syn. optic radiations of Gratiolet; geniculocalcarine pathway; geniculostriate pathway.
References in periodicals archive ?
A predominantly superior homonymous quadrantanopic field defect ('pie-in-the-sky') may be due to a temporal lobe lesion that impinges on the inferior bundle of nerve fibres that form the optic radiations (Figure 3 H).
c) A contralateral, homonymous, inferior quadrantanopia arises from damage to the inferior fibres of the optic radiations.
d) Lesions of the anterior optic radiations are more congruous than those involving the posterior radiations.