Cranial nerves prep Flashcards
Upper motor neurone fibres follow which tract?
Follow the corticobulbar tract to the respective nuclei in the brain stem.
Lower motor neurone (LMN) fibres emerge from where?
Anteroinferior surface of brain
Olfactory nerve connects directly with?
Sensory nerve.
Connects directly with the cerebrum.
Sense of smell
How might olfactory nerve be tested?
- ask patient to identify a range of substances, which recognisable smells.
Optic nerve
Sensory nerve, perception of light.
Connects directly with the cerebrum.
Objected on our temporal field of vision are perceived by…
Fibres on nasal aspect of retina
Nasal fibres leave optic nerve at…
Optic chiasm
Testing visual fields allows you to…
Determine site of a lesion
Testing visual fields allows you to…
Determine site of a lesion
Damage to optic nerve between optic nerve and chiasm results in…
Affected eye unable to perceive light. Unilateral blindness. Monocular vision.
Bi-temporal hemianopia
Unable to see things in temporal side of field of vision.
Can see things directly ahead, in nasal field.
PERLA
Pupils equal and reactive to light and accomodation.
Visual acuity test
Snellen’s chart.
Series of different sized characters which are viewed from a distance of 6metres away.
Glaucoma
Increased pressure within the eye
Retinopathies
Affecting the light sensitive cells
Visual field refers to
Total area in which objects can be seen in peripheral vision as you focus your eyes on a central point.
Describe the blind spot
Area of no cones or rod.
Retina unable to perceive light.
Creates a blind spot in which a visual field deficit is present.
Scotoma
Small visual field deficit due to conditions which affect the passage of perception of light within the eye.
