Pupillary reflex

(physiology) Contraction of the pupil in response to stimulation of the retina by light. Also known as Whytt's reflex. Contraction of the pupil on accommodation for close vision, and dilation of the pupil on accommodation for distant vision. Contraction of the pupil on attempted closure of the eye. Also known as Westphal-Pilcz reflex; Westphal's pupillary reflex.

A reflex resulting in change in the diameter of the pupil of the eye.

The noun has one meaning:

Meaning #1: reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller
  Synonyms: light reflex, miosis, myosis

Pupillary reflex refers to one of the reflexes associated with pupillary function.

Types include:

• Pupillary light reflex
• Accommodation reflex

Although pupillary dilation is not usually called a "reflex", it is still usually considered a part of this topic.

Accommodation and vergence are also known as the "near response", while inhibition of the ciliary muscle is also known as the "far response".

This anatomy article is a stub. You can help Wikipedia by expanding it. v • d • e

v • d • e Sensory system: Visual system and eye movement pathways Visual perception 1° (Retina → Optic nerve → Optic chiasm → Optic tract → LGN of Thalamus) → 2° (Optic radiation → Cuneus and Lingual gyrus of Visual cortex → Blobs → Globs) Muscles of orbit Tracking Smooth pursuit: Parietal lobe · Occipital lobe Saccade: Frontal eye fields Physiologic nystagmus → Fixation reflex → PPRF Horizontal gaze PPRF → Abducens nucleus → MLF → Oculomotor nucleus → Medial rectus muscle Vertical gaze Rostral interstitial nucleus → Oculomotor nucleus, Trochlear nucleus → Muscles of orbit Vestibulo-ocular reflex Semicircular canal → Vestibulocochlear nerve → Vestibular nuclei → Abducens nucleus → MLF → Oculomotor nucleus → Medial rectus muscle Pupillary reflex Pupillary dilation 1° (Posterior hypothalamus → Ciliospinal center) → 2° (Superior cervical ganglion) → 3° (Sympathetic root of ciliary ganglion → Nasociliary nerve → Long ciliary nerves → Iris dilator muscle) Pupillary light reflex (constriction) 1° (Retina → Optic nerve → Optic chiasm → Optic tract → Pretectal nucleus) → 2° (Edinger-Westphal nucleus) → 3° (Oculomotor nerve → Parasympathetic root of ciliary ganglion → Ciliary ganglion) → (4° Short ciliary nerves → Iris sphincter muscle) Accommodation vergence 1° (Retina → Optic nerve → Optic chiasm → Optic tract → Visual cortex → Brodmann area 19 → Pretectal area) → 2° (Edinger-Westphal nucleus) → 3° (Short ciliary nerves → Ciliary ganglion → Ciliary muscle) Circadian rhythm Retina → Hypothalamus (Suprachiasmatic nucleus) eye navs: anat/adnexa anat/pathways/physio/dev, noncongen/congen/neoplasia, eponymous signs, proc

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