NEURO UNIT 2 Flashcards
Lesion on the Right Optic Nerve causes
Right Eye blindness
Lesion on the right lateral to the optic chiasm causes
Right Eye blindness and left lower impairment
Lesion on the optic chiasm causes
Left Homogenous Hemianopsia
Lesion on the right optic tract causes
Left Homogenous Hemianopsia
Lesion on the Myers Loop (Optic Radiations) causes
Upper Left Superior Quadrinopia
Lesion on the Right Lateral Geniculate Nucleus causes
Left Homogenous Hemianopia
Lesion on the Right Superior Optic Radiation causes
Left Homogenous Contralateral Left Inferior Quadrinopia
Lesion on the Right Optic Radiation causes
Left Homogenous Hemianopsia
Temporal is what side of the eye
Outside of the eye
Nasal is what side of the eye
Inside of the eye
Optic Neuritis is
inflammation of the optic nerve (CN II)
Double Vision most common cause is
Internuclear ophthalmoplegia (INO)
- damage to the white matter pathways (MLF)
Nystagmus is
an involuntary movement of the eyes that is rhythmic
- INO
- Cerebellum is involved
Primary Supranuclear Palsy symptoms
- Vertical gaze palsy
- postural instability
- axial rigidity
-behavioral changes
Midbrain degeneration is damage to the rostral interstitial nucleus and is seen by a hummingbird sign on a MRI
What two Cranial Nerves are often injured together due to wrapping around each other?
CN VII and CN VI
(Facial and Abducens)
Lateral gaze palsy and ipsilateral facial paralysis
Medial Longitudinal Fasciculus
White matter pathway that connects CN III, IV, and VI
-coordinates lateral gaze
Retinohypothalamic Pathway function
Regulates sleep wake cycles
Retinohypothalamic pathway -
- Specialized cells in retina
- Optic Nerve
- Hypothalamus (suprachiasmatic nucleus)
- Spinal Cord (sympathetic ganglia)
- Pineal Gland (Release melatonin)
Accommodation Reflex is driven by
CN III and midbrain
Accommodation Reflex function
- Prepare for near viewing
- Changing the shape of the lens
- Pupillary constriction
- Convergence of the eyes
Accommodation Reflex Pathway
- Primary Visual Pathway
- Visual Association areas
- Supraoculomotor Nuclei in Midbrain
- Edinger Westphal nucleus (Iris Sphincter and Ciliary muscles of lens)
- CN III Motor (convergence)
Midbrain visual projection to Edinger-Westphal nucleus function
Control the amount of light that reaches the retina
Midbrain visual projection to Edinger-Westphal nucleus pathway
- Light
- CN II
- Pretectal area of Midbrain
- Bilateral Projections (Edinger-Westphal nucleus)
- Parasympathetic neurons to CN III
- Synapse on pupillary sphincter muscles
Midbrain visual projection to superior colliculus function
Spatial map for orientating of the head
Midbrain visual projection to superior colliculus pathway
Reflexive Pathway
2. CN II
3. Optic Tract
4. Superior Colliculi
5. Auditory information is integrated in superior colliculi
Attentional Pathway
1. CN II
2. Optic Tract
3. Superior Colliculi
4. Dorsal / Ventral stream and thalamus (pulvinar nuclei)
Dorsal Stream
Where and How to
Analyzes motion and spatial relationships
Ventral Stream
What/Objects processing
Analyzes forms, color, size, texture
Assigns meaning
