uAccommodation is the adjustment of the eye to see either near or distant objects clearly. It is the process by which light rays from near objects are brought to a focus on the sensitive part of retina. It is achieved by , three adjustments made in eyeballs. u
1.Convergence of the eyeballs due to contraction of the medial recti
2.Constriction of the pupil due to the contraction of constrictor pupillae of iris
3.Increase in the curvature of the lens due to contraction of ciliary muscle.
u
u Involves both skeletal muscle ( medial recti) and smooth muscle (ciliary muscle and sphincter pupillae)
uThe center for accommodation lies in frontal eye field (area 8) in frontal lobe of cerebral cortex.
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