Search results
Results from the WOW.Com Content Network
The ciliary muscle is an intrinsic muscle of the eye formed as a ring of smooth muscle [3] [4] in the eye's middle layer, the uvea (vascular layer). It controls accommodation for viewing objects at varying distances and regulates the flow of aqueous humor into Schlemm's canal .
Light from a single point of a distant object and light from a single point of a near object being brought to a focus. The accommodation reflex (or accommodation-convergence reflex) is a reflex action of the eye, in response to focusing on a near object, then looking at a distant object (and vice versa), comprising coordinated changes in vergence, lens shape (accommodation) and pupil size.
Parasympathetic action helps in digestion and absorption of food by increasing the activity of the intestinal musculature, increasing gastric secretion, and relaxing the pyloric sphincter. It is called the “rest and digest” division of the ANS. [24] The parasympathetic nervous system decreases respiration and heart rate and increases digestion.
Ciliary ganglion with parasympathetic fibers of ciliary nerves. The parasympathetic innervation of the ciliary body is the most clearly understood. Presynaptic parasympathetic signals that originate in the Edinger-Westphal nucleus are carried by cranial nerve III (the oculomotor nerve ) and travel through the ciliary ganglion .
Ciliary muscle contraction initiates a pressure gradient between the vitreous and aqueous compartments that support the anterior lens shape. It is in this lens shape that the mechanically reproducible state of a steep radius of curvature in the center of the lens with slight flattening of the peripheral anterior lens, i.e. the shape, in cross ...
The muscles of the eye such as ciliary muscles – become stronger after two months of age, allowing infants to focus on particular objects through contraction and relaxation. Their retinal images are also smaller compared to adults due to shorter distances from the retina to the cornea of the infants' eye. [ 1 ]
The tension is released, by contraction of the ciliary muscle, to allow the lens to become more round, for close vision. This implies the ciliary muscle, which is outside the zonula, must be circumferential, contracting like a sphincter, to slacken the tension of the zonula pulling outwards on the lens.
The long ciliary nerves are 2-3 [1] nerves that arise from the nasociliary nerve (itself a branch of the ophthalmic branch (CN V 1) of the trigeminal nerve (CN V)). They enter the eyeball to provide sensory innervation to parts of the eye, and sympathetic visceral motor innervation to the dilator pupillae muscle .