GROSS ANATOMY
CRANIAL NERVES
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Olfactory (I)
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Optic sensory (II)
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Oculomotor (III, IV, VI)
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Trigeminal (V)
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Detailed explanation-1: -The 3rd cranial nerve also controls eye muscle movement. Cranial Nerve IV (Trochlear) controls downward eye movement toward the nose, and Cranial Nerve VI (Abducens) controls horizontal eye movement toward the temple. The ability to move the eye in all other directions is controlled by CN III.
Detailed explanation-2: -Cranial nerves III (CNIII) (oculomotor), IV (trochlear), and VI (abducens) control the position of the eyeballs; CNIII influences the position of the eyelids and the size of the pupils.
Detailed explanation-3: -3rd, 4th, and 6th Cranial nerves Extraocular movements controlled by these nerves are tested by asking the patient to follow a moving target (eg, examiner’s finger, penlight) to all 4 quadrants (including across the midline) and toward the tip of the nose; this test can detect nystagmus and palsies of ocular muscles.
Detailed explanation-4: -The abducens nerve or abducent nerve, also known as the sixth cranial nerve, cranial nerve VI, or simply CN VI, is a cranial nerve in humans and various other animals that controls the movement of the lateral rectus muscle, one of the extraocular muscles responsible for outward gaze.
Detailed explanation-5: -The oculomotor nerve helps to adjust and coordinate eye position during movement. Several movements assist with this process: saccades, smooth pursuit, fixation, accommodation, vestibulo-ocular reflex, and optokinetic reflex. Saccades are rapid, jerky motions of the eye.