Indirect Light Reflex Pathway. Pre ganglionic parasympathetic fibres enter the oculomotor nerve leave the branch to the inferior oblique and synapse in the ciliary ganglion. And the sphincter pupillae of.
The pupillary light reflex or photopupillary reflex is a reflex that controls the diameter of the pupil in response to the intensity of light that falls on the retinal ganglion cells of the retina in the back of the eye thereby assisting in adaptation of vision to various levels of lightness darkness. Pupilllary light reflex pathways author. Thus the pupillary light reflex regulates the intensity of light enteri.
A greater intensity of light causes the pupil to constrict whereas a lower intensity of light causes the pupil to dilate.
Afferent pathway stimulation of the retinal receptors by light initiate an impulse which is transmitted from the eye via the optic nerve with the majority then crossing over at the optic chiasm to the contralateral optic tract. Indirect responses can aid in the evaluation of retinal function as a positive response indicates the continuity of a neurological pathway connecting the eyes e g. And the sphincter pupillae of. The mechanisms behind the direct and indirect reflex examination of cranial nerves ii and iii are helpful in understanding abnormal findings.
