pretectal centre
Quick Summary
The pretectal nucleus is a relay center in the midbrain that is crucial for pupillary responses to light. It receives input from the retina and visual cortex and plays a role in visual reflexes, particularly those involving eye movement and visual processing. This nucleus is part of the tegmentum, a region within the midbrain that also includes the red nucleus, periaqueductal gray, and substantia nigra, all involved in various motor and sensory functions. The pretectal nucleus's connection to the Edinger-Westphal nucleus facilitates the pupillary light reflex, ensuring that both pupils constrict even when only one eye is exposed to light.12
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human nervous systemThe eye…transmit luminosity information to the pretectum, where particular types of neurons relay the information to parasympathetic preganglionic neurons located in the Edinger-Westphal nucleus of the midbrain. The axons of these neurons exit the ventral surface of the midbrain and synapse in the ciliary ganglion. From there, parasympathetic postganglionic neurons innervate…
Read More…transmit luminosity information to the pretectum, where particular types of neurons relay the information to parasympathetic preganglionic neurons located in the Edinger-Westphal nucleus of the midbrain. The axons of these neurons exit the ventral surface of the midbrain and synapse in the ciliary ganglion. From there, parasympathetic postganglionic neurons innervate…
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human eyePupillary pathways…instead to a midbrain region—the pretectal centre—where they mediate (transmit) reflex alterations in the size of the pupil. Thus, in bright light, the pupils are constricted; this happens by virtue of the pupillary light reflex mediated by these special nerve fibres. Removal of the occipital cortex, although it causes blindness…
Read More…instead to a midbrain region—the pretectal centre—where they mediate (transmit) reflex alterations in the size of the pupil. Thus, in bright light, the pupils are constricted; this happens by virtue of the pupillary light reflex mediated by these special nerve fibres. Removal of the occipital cortex, although it causes blindness…
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