Save
Upgrade to remove ads
Busy. Please wait.
Log in with Clever
or
show password
Forgot Password?
Don't have an account?  Sign up 
Sign up using Clever
or
Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account. Your email address is only used to allow you to reset your password. See our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
focusNode
Didn't know it?
click below
 
Knew it?
click below
Don't Know
Remaining cards (0)
Know
0:00
edit
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Visual System

Visual System - Neuroanatomy - HST130

QuestionAnswer
CN II modality SSA
Optic nerve is formed by axons of ___ retinal ganglion cells
Transection of optic nerve causes... Ipsilateral blindness with no direct pupillary light reflex
Cause of binasal hemianopia Bilateral lateral compression of optic chiasm (ie by calcified internal carotids)
Pituitary tumor often causes what visual defect Compression of optic chiasm, causing bitemporal hemianopia
Each optic tract receives fibers from... Ipsilateral temporal hemiretina and contralateral nasal hemiretina
Each optic tract projects to... Ipsilateral LGN, superior colliculus, & pretectal nuclei
Transection of optic tract causes... Contralateral hemianopia
LGN layers come from... 1,4,6 are crossed (from CL eye). 2,3,5 are uncrossed (from IL eye).
Parvocellular system Layers 3-6. Sense color/form
Magnocellular system Layers 1-2. Sense movement/contrast
Upper division of optic radiations projects to ___ upper bank of calcarine sulcus (Cuneus)
Lower division of optic radiations projects to ___ lower bank of calcarine sulcus (Lingual gyrus)
Upper division of optic radiations receives input from which retinal & visual fields? Upper retinal quadrants, lower visual fields
Meyer's loop Lower division of optic radiations
Meyer's loop contains input from which retinal & visual fields? Lower retinal quadrants, upper visual fields
Visual cortex is Brodmann # 17
Transection of upper division of optic radiations causes... contralateral lower quadrantanopia
Transection of Meyer's loop causes... contralateral upper quadrantanopia (pie in the sky)
Lesions of visual cortex cause... Contralateral hemianopia with macular sparing
Posterior area of striate cortex represents... macula
Homonymous loss Visual field losses are similar for both eyes
Heteronymous loss Visual field losses are non-overlapping for the 2 eyes
Damage to optic nerve causes IL/CL loss IL
Damage to optic chiasm causes ___ loss Heteronymous
Damage behind optic chiasm causes ___ loss Homonymous
Which CNs give afferent and efferent limbs of pupillary light reflex? Afferent: CNII. Efferent:CNIII
Pathway for pupillary light reflex Ganglion cells --> Optic nerve --> Optic Chiasm --> Optic Tract --> Brachium of Superior Colliculus --> Pretectal nuclei --> Posterior Commissure --> EW Nucleus --> CN III --> Ciliary Ganglion --> Pupillary sphincter
Interruption of pupillary dilation reflex results in ___ Ipsilateral Horner's Syndrome (miosis, ptosis, enophthalmos,)
Pathway for pupillary dilation reflex Paraventricular nucleus of Hypothalamus --> Ciliospinal Ctr of Budge (T1-T2) --> Superior cervical ganglion --> Dilator muscle of iris
One-and-a-half syndrome Bilateral MLF lesions & unilateral lesion to nucleus of VI. The only muscle that works in lateral conjugate gaze is the intact lateral rectus
Marcus Gunn pupil Due to lesion of CN II. Loses pupillary light reflex in that eye.
MLF syndrome Damage to MLF unilateral. Means you won't get medial conjugate gaze in the eye damaged
CN III Palsy produces... down and out
One common cause of CN III Palsy Posterior communicating aneurysm
CN VI Palsy presents clinically as... Ipsilateral eye deviated medially
PPRF. Location? Paramedian Pontine Reticular Formation. Superior to Nuc of VI
Saccades pathway Frontal Eye Field (Brodmann 8) --> CL PPRF --> Nuc of VI --> MLF (crosses) --> Nuc of III
Smooth pursuit pathway Frontal Eye Field --> Pontine Nuclei --> Flocculonodular Lobe --> JRB --> Vestibular Nuclei --> CL Nuc of VI --> MLF (crosses) --> Nuc of III
Horizontal vs Vertical saccades are mediated by what motor programs.... Horizontal - PPRF. Vertical - riMLF
riMLF Rostral interstitial nucleus of MLF (Bilateral fibers for elevator muscles of both eyes)
Superior colliculus fxns Saccades, coordination of head/eye movements
Created by: xin_gao1984
 

 



Voices

Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!
"Know" box contains:
Time elapsed:
Retries:
restart all cards