Cortical development Flashcards
Function of V2
Binocularity
Causes of amblyopia
Deprivational, strabismic, refractional
What would a cortical dominance graph look like if alternating tropia?
1 and 7 large, in between empty because not binocular
What’s activated when looking at a checkerboard
LGN and Cortex
V4 general purposes (2)
Color and face recognition
Connections that V2 makes and describe
V1: Thick stripe
V3: Thick pale stripe interblobs
V4: Thin stripe to color blobs
V5: Not specified (Thick stripe?)
True or false: V3 also utilizes parvo cells
True! Foveate on oncoming objects
Where does face recognition occur?
V4 at the fusiform (face) gyrus
Problems that can arise from damage to V4
Prosopagnosia, Achromatopsia (Still 20/20 vision)
With V4 you get binocular rivalry. With colored dots, you just get luster whereas with a picture overlaid with words (like the chimp) you get confusion
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Where does parvo end?
V4
Where does magno end?
V5
Purpose of V1
Edge detector
What happens with damage to V5?
Akinetopsia
Where is biological motion seen
Anterior Superior temporal sulcus (V5)
Where do you find visual attention and feature binding?
Pulvinar
Where is the pulvinar located?
Thalamus
Where is change blindness seen?
Pulvinar. Pulvinar poor at seeing simultaneous picture changes. Amacrine picks up signal better if sequential
Top down vs Bottom up attention
Top down is sense directed by frontal lobe
Bottom up is when you sense something before you think about it
What’s visual capture?
Visual stimulus associated with sound
What’s visual zoom?
Ignore everything you’re not visually focusing on. Example of counting how many times ball being passed while dumb bear walks through background
Figure ground?
Ability to tease background from foreground
Bistable figures
Things that can be switched from one object to another. Example is wineglass/face illusion
Visual neglect usually neglects which field? Why?
Left field. Left field holds language and logic. Would be hard to ignore. Right brain holds things not used on daily basis. The mute hemisphere
Causes of acquired agnosia
Stroke, Trauma, Toxins
Types of agnosia
Apperceptive, Associative, Simultagnosia
Apperceptive Agnosia? Where’s the problem
Can see objects, but can’t perceive it. Example, when asked to match pictures, may match X with O or a triangle with a circle
Problem between retina and cortex. Right inferior parietal lobe
Simultagnosia
Can’t see multiple objects at once
Associative agnosia? Where’s the problem
Can’t associate object with word
Problem at occipital/temporal junction by Wernicke’s
List color agnosias
Color agnosia: can’t associate colors with objects
Color anomia: Distinguishing colors
Cerebral achromatopsia: Not being able to see color
What’s visual spatial agnosia?
Deficiency in stereo and topographical locations
What’s Anton syndrome?
Where you’re cortically blind but you don’t realize it
Causes of cortical blindness?
Birth defect, trauma, Creutzfeld Jakob dementia, Epilepsy meds
When does blindsight occur?
Failure of V1
What most commonly causes blindsight?
Car accidents/coup and contracoup accidents
How can you prove cortical blindness?
Using VEP
Paths should still work even if can’t see
Differentiate true blindness
Where is blindsight seen? What age is most promising
Spared Islands of V1 in injuries as child. Neuroplasticity helps you out
Most babies born with intermittent tropia that will resolve
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When are visual skills developed
About 3 months
When does color vision develop
1.5 years into adolescence
When does acuity develop?
5 years. When brain starts linking up to other parts.
Ex: can’t verbalize what you see if not connected to Wernicke’s
Where is the OKN drum seen in the brain
Pretectal nucleus and cerebellum
What are the VAs and REs for babies. Write them down, fool
1mo: 20/640 +2.25 4mo 20/225 +2.00 6mo 20/100 +1.75 12mo 20/95 +1.57 2yr 20/60 +1.20 3yr 20/30 +1.00 4yr 20/25 +1.13
When do babes have a normal peak and what is it?
4 years old 4cpd = 20/150
When do babies have adult function?
9 yo
What’s baby CPD at 1 month?
2 CPD(limitation due to retinal immaturity)
When does amblyogenesis occur?
6 mo - 2yrs
Stroop effect is a figure-ground effect
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