What are 2 parts of pupillary light reflex?

The pupillary light reflex constricts the pupil in response to light, and pupillary constriction is achieved through the innervation of the iris sphincter muscle.

What is the function of the pupillary light reflex quizlet?

The pupillary light reflexes function to protect the retina (part of the CNS) from damage resulting from excessively bright light.

What does it mean if your pupils do not react to light?

When your pupil shrinks (constricts), it’s called miosis. If your pupils stay small even in dim light, it can be a sign that things in your eye aren’t working the way they should. This is called abnormal miosis, and it can happen in one or both of your eyes.

What is the pupillary reflex mediated by?

oculomotor nucleus
Pupillary reflexes involve the autonomic (Edinger-Westphal) component of the oculomotor nucleus. In the light reflex, the pupils constrict when light is shone on the retina. If one eye only is stimulated, both pupils constrict, the so-called consensual reflex.

What is the response of the pupil when light is shone on it quizlet?

Both pupils dilate in response to light. Both pupils constrict in response to light.

What part of the brain is responsible for initiating the pupillary reflex?

The Hypothalamus The roles it plays in the pupillary reflexes demonstrates the importance of this control center. The optic nerve projects primarily to the thalamus, which is the necessary relay to the occipital cortex for conscious visual perception.

What part of the brain controls pupillary reflex?

The pupillary light reflex pathway lies at the level of the midbrain-diencephalic junction and involves the pretectal olivary nucleus of the pretectal area, which lies anterolateral to the superior pole of the superior colliculus; the posterior commissure, which forms the roof of the cerebral aqueduct (of Sylvius); the …

What kind of reflex is left consensual pupillary reflex?

Left consensual pupillary reflex is the left pupil’s indirect response to light entering the right eye, the contralateral eye. Right direct pupillary reflex is the right pupil’s response to light entering the right eye.

What is the anatomical pathway of pupillary light refles?

Pupillary pathways with diagram.(5) J2016 (1) Pupillary fibers in the nerve (2) Chiasmal decussation (3) Uncrossed fibers (4) Crossed fibers

Why does the ciliospinal reflex cause pupillary dilation?

If the pupillary dilation is due to the ciliospinal reflex, prolonged pupillary light stimulation should constrict the pupils However, prolonged light stimulation cannot overcome pupillary dilation caused by bilateral third nerve palsies and midbrain dysfunction.

What causes direct light reflex of the ipsilateral pupil?

The ipsilateral efferent limb transmits nerve signals for direct light reflex of the ipsilateral pupil. The contralateral efferent limb causes consensual light reflex of the contralateral pupil.

What are 2 parts of pupillary light reflex? The pupillary light reflex constricts the pupil in response to light, and pupillary constriction is achieved through the innervation of the iris sphincter muscle. What is the function of the pupillary light reflex quizlet? The pupillary light reflexes function to protect the retina (part of the CNS)…