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The superior colliculus is a paired structure of the dorsal midbrain and is part of the midbrain tectum. The two superior colliculi are situated inferior/caudal to the pineal gland and the splenium of corpus callosum .
The midbrain is the shortest segment of the brainstem, measuring less than 2cm in length. It is situated mostly in the posterior cranial fossa, with its superior part extending above the tentorial notch. [2] The principal regions of the midbrain are the tectum, the cerebral aqueduct, tegmentum, and the cerebral peduncles.
Parinaud's syndrome results from injury, either direct or compressive, to the dorsal midbrain. Specifically, compression or ischemic damage of the mesencephalic tectum, including the superior colliculus adjacent oculomotor (origin of cranial nerve III) and Edinger-Westphal nuclei, causing dysfunction to the motor function of the eye.
In the brain, the corpora quadrigemina (Latin for "quadruplet bodies") are the four colliculi—two inferior, two superior—located on the tectum of the dorsal aspect of the midbrain. They are respectively named the inferior and superior colliculus. The corpora quadrigemina are reflex centers involving vision and hearing.
The midbrain tegmentum is situated anteriorly to the cerebral aqueduct. [3] The portion of the tegmentum posterior to the aqueduct is the tectum . [ 1 ] The superior and inferior colliculi that make up the corpora quadrigemina are situated posteriorly to it.
The superior colliculus is positioned above the inferior colliculus, and marks the rostral midbrain. It is involved in the special sense of vision and sends its superior brachium to the lateral geniculate body of the diencephalon. The tegmentum which forms the floor of the midbrain, is ventral to the cerebral aqueduct.
In neuroanatomy, the pretectal area, or pretectum, is a midbrain structure composed of seven nuclei and comprises part of the subcortical visual system.Through reciprocal bilateral projections from the retina, it is involved primarily in mediating behavioral responses to acute changes in ambient light such as the pupillary light reflex, the optokinetic reflex, and temporary changes to the ...
It arises from the superior colliculus of the mesencephalic (midbrain) tectum, and projects to the cervical and upper thoracic spinal cord levels. [2] It mediates reflex turning of the head and upper trunk in the direction of startling sensory stimuli (visual, auditory, or skin). [2] It arises from the deep layers of the superior colliculus.