Dictionary > Accommodation reflex

Accommodation reflex

Definition
noun, plural: accommodation reflexes
A reflex reaction of the eye in response to focusing on near object followed by looking at a distant object (or vice versa)
Supplement
In physiology, a reflex is an immediate involuntary response or a reaction to a stimulus. The response is innate and need not to be learned and the body acts accordingly without first thinking about what to do. The human body has several reflexes. The accommodation reflex is one of them.
The accommodation reflex is a reflex reaction of the eye when it focuses on a near object and then looks at a distant object (or vice versa). The eye undergoes coordinated alterations, such as convergence, the lens shape and the pupil size. In particular, the pupil constricts and the lens increases its curvature by the contraction of the ciliary muscle to enable pupil and lens accommodation, respectively. Convergence refers to the ability of the eye to move inward and toward each other to facilitate focus on near objects. It is enabled by the contraction of the medial rectus muscles of both eyes and the relaxation of the lateral rectus muscles. The motor neurons in the oculomotor nerve innervate the medial rectus.
Synonym(s):

  • accommodation-convergence reflex

See also:

  • reflex
  • pupil
  • retina
  • lens


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