The pupillary light reflex allows the eye to adjust the amount of light reaching the retina and protects the photoreceptors from bright lights. The iris contains two sets of smooth muscles that control the size of the pupil (Figure 7.2).
What is the function of these pupillary reflex quizlet?
What is the function of these pupillary responses? The purpose of the pupillary response would be to protect the eye from too much sunlight and to aid vision in very light or dark situations.
What is pupillary response quizlet?
pupillary accommodation reflex. the reduction of pupil size in response to an object coming close to the eye. both.
What is pupillary response mean?
Pupillary light response (PLR) is the reduction of pupil size in response to direct light. This is the most common stimulus for pupillary constriction. A direct papillary reflex means that the pupil quickly constricts briskly when the light is shone in that eye.
What is pupillary pathway?
Pathway: Afferent pupillary fibers start at the retinal ganglion cell layer and then travel through the optic nerve, optic chiasm, and optic tract, join the brachium of the superior colliculus, and travel to the pretectal area of the midbrain, which sends fibers bilaterally to the efferent Edinger-Westphal nuclei of
What happens during a pupillary light reflex?
A greater intensity of light causes the pupil to constrict (miosis/myosis; thereby allowing less light in), whereas a lower intensity of light causes the pupil to dilate (mydriasis, expansion; thereby allowing more light in). Thus, the pupillary light reflex regulates the intensity of light entering the eye.
What is the response of the pupil when light is shone on it quizlet?
The patient’s pupils are fixed and dilated in response to light. Both pupils dilate in response to light.
What was the response of the pupil in the opposite eye quizlet?
Pupillary Light Reflex Exercise: What was the response of the pupil in the opposite eye when light was shown on the first eye? The opposite pupil also contracts via the consensual light reflex.
What is the category of pupillary reflex quizlet?
The pupillary light reflex is an example of a (n) Autonomic reflex.
What pupil dilation means?
Muscles in the colored part of your eye, called the iris, control your pupil size. Your pupils get bigger or smaller, depending on the amount of light around you. In low light, your pupils open up, or dilate, to let in more light. When it’s bright, they get smaller, or constrict, to let in less light.
Why is pupil assessment important?
Pupillary assessment is an important part of neurological assessment because changes in the size, equality and reactivity of the pupils can provide vital diagnostic information in the critically ill patient (Smith, 2003). Both pupils should be the same shape, size and react equally to light.
What is Marcus Gunn pupil?
Marcus Gunn pupil (MGP) is the term given to an abnormal pupil showing aberrant pupillary response in certain ocular disorders. In literature, the term is often used synonymously with Marcus Gunn phenomenon or relative afferent pupillary defect (RAPD).  After exposure to bright light, a normal pupil constricts.
How are pupil responses regulated?
The size of the pupil is controlled by the activities of two muscles: the circumferential sphincter muscle found in the margin of the iris, innervated by the parasympathetic nervous system: and the iris dilator muscle, running radially from the iris root to the peripheral border of the sphincter.
Why do pupils constrict with light?
In bright light, your pupils get smaller (constrict) to limit the amount of light that enters. In the dark, your pupils get bigger (dilate). That allows more light in, which improves night vision.