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 ?
Figure 3 shows that the five thalamocortical white matter projections appeared visually similar across all three groups and also that the optic radiations remained present in the CB and LB groups, despite the absence of visual input (Figure 3, first column).
Data from the present study confirm that the connectivity between the thalamus and the occipital cortex in the human is preserved in congenitally blind individuals, as testified by the absence of group differences in posterior thalamic clusters and normal looking optic radiations on visual inspection.
Jan acknowledges this in a Comment, of which he was a contributing author, that was published in JVIB in February 2010 that defined CVI as "impaired vision that is due to bilateral dysfunction of the optic radiations [white matter] or visual cortex [gray matter] or both" (Roman et al., 2010, p.
Second, the child must have some brain injury, a suspected brain injury, or a malformation that causes dysfunction of the optic radiations or visual cortex or both.
The optic radiations pass through the parietal lobe before passing through the temporal lobe and then reaching the visual cortex (Figure 3).
Upon leaving the LGN, the upper fibres of the optic radiations take a relatively direct course backwards, spreading in a broad fan through tile parietal lobe to terminate in the occipital visual cortex.