The area pretectalis is located in the diencephalon.
Anatomy
The area pretectalis is located at the level of the posterior commissure, immediately rostral to the superior colliculi. The area pretectalis can be divided into various cell groups, the so-called pretectal nuclei, which have connections with the visual system. The nuclei have different designations in the literature; a common classification distinguishes the nucleus of the optic tract, the anterior pretectal nucleus, the olivary pretectal nucleus, and a posterior pretectal nucleus.
Afferents
The most important afferents to the area pretectalis originate from the retina and terminate mainly contralaterally in the nucleus of the optic tract and the olivary pretectal nucleus. Additional afferents to the pretectal nuclei originate from specific visually associated areas of the cerebral cortex, the ventral lateral geniculate body, and the superior colliculus1.
Efferents
The efferents of the area pretectalis are in part reciprocal to its afferents. Particularly prominent efferents project to the lateral geniculate body, superior colliculus, interstitial nucleus of Cajal, the ocular motor nuclei including the Edinger-Westphal nucleus, and the olive2.
Functional significance
The area pretectalis plays an important role as a relay station in the pupillary light reflex pathway. In particular, the olivary pretectal nucleus projects bilaterally to specific portions of the parasympathetic oculomotor nucleus, with the crossed fibers passing through the posterior commissure3.
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