REFLEXES OF THE EYE - MODULE

Question 1

What reflex allows for the adjustment of changing light conditions

Answer 1

the pupillary light reflex

Question 2

What muscle is responsible for constriction of the pupil?

Answer 2

constrictor pupillae

Question 3

what nervous system leads to pupil constriction

Answer 3

parasympathetic

Question 4

in the pupillary light reflex, light reaches the retina and informations travels via the optic nerve to the …

Answer 4

pretectal nuclei in the midbrain

Question 5

in the pupillary light reflex, fibres from each pretectal nucleus sends bilateral projections to the

Answer 5

edinger-westphal nuclei

Question 6

in the pupillary light reflex, preganglionic parasympathetic fibers from the edinger-westphal nuclei travel with the oculomotor nerve to the…

Answer 6

ciliary ganglia

Question 7

what is the final step to the pupillary light reflex

Answer 7

postganglionic parasympathetic fibres travels as the short ciliary nerves and innervate the contrictor pupillae muscles

Question 8

if the right CN III is damaged, shining light in the right eye will result in

Answer 8

no constriction of right pupil but constriction of left pupil

Question 9

The pupillodilator reflex relies on what nervous system

Answer 9

the sympathetic

Question 10

When is the pupillodilator reflex activated

Answer 10

in response to strong emotional state

Question 11

what muscle is responsible for he pupillodilator relfex

Answer 11

the dilator pupillae muscle

Question 12

What initiates the pupillodilator reflex

Answer 12

sympathetic neurons in the lateral horn of spinal segment T1 are stimulated by higher brain systems in response to emotional stimulus

Question 13

in the pupillodilator reflex, sympathetic fibres leave the spinal cord and travel up the sympathetic trunk to the…

Answer 13

superior cervical ganglion

Question 14

in the pupillodilator reflex, postganglionic fibres travel along the _____ into the cranium

Answer 14

carotid artery

Question 15

in the in the pupillodilator reflex, once in the cranium the postganglionic fibres travel to the orbit along the…

Answer 15

ophthalmic division of the trigeminal nerve

Question 16

in the pupillodilator reflex, the fibres branch off V1 as the ___ and innervate the dilator pupillae muscles of the iris

Answer 16

long cilary nerves

Question 17

What is the pathway called that causes blinking of the eye when the eye senses touch or pain

Answer 17

corneal bink relfex

Question 18

in the corneal blink reflex, following sensory stimuli to the cornea, sensory afferent travel via the _______ to the _____

Answer 18

ophthalmic division of the trigeminal nerve to the trigeminal sensory nucleus

Question 19

in the corneal blink reflex, sensory afferents synapse with spinal trigeminal interneurons, which project to the

Answer 19

facial motor nucleus

Question 20

in the corneal blink reflex, fibres from the facial motor nucleis innervate the

Answer 20

circular orbicularis oculi muscles

Question 21

Convergence and divergence of the eyes is caused by signal from the

Answer 21

vergence centers

Question 22

where are the vergence centers located

Answer 22

in the rostral midbrain

Question 23

the vergence centres signal the ____ causing convergence

Answer 23

oculomotor nuclei

Question 24

the vergence centres signal the ____ causing divergence

Answer 24

abducens nuclei

Question 25

In order to focus on a near object what 3 things must occur

Answer 25

1. convergence of the eyes
2. thickening of the lens
3. constriction of the pupil

Question 26

What area of the brain coordinates the 3 things that must occur in order to focus on something near

Answer 26

the supraoculomotor area in the rostral midbrain

Question 27

In the accommodation reflex, the supraoculomotor area sends bilateral projections to the _____ and the _____

Answer 27

oculomotor nucleus and the edinger-Westphal nuclei

Question 28

in the accommodation relfex, innervation of the oculomotor nuclei results in ____

Answer 28

convergence of the eyes via the activation of the medial rectus muscle

Question 29

in the accommodation relfex, innervation of the edinger-Westphal nuclei results in ____

Answer 29

parasympathetic innervation of the constricor pupillae muscles resulting in constriction of the eyes

Question 30

Int he accommodation reflex, what causes the lens to change shape and increase curvature

Answer 30

parasympathetic stimulation of the ciliary muscles