disorders of visual processing Flashcards
“software” of the visual system
visual processing
“hardware of the visual system
visual efficiency
visual efficency
neurodevelopment of eye tracking accommodation, and binocular vision
visual processing
how the eyes interface with the rest of the brain and body (interpret visual stimuli)
disorders of visual sensory pathways
lesions of pathways from the retina, optic nerve to the striate cortex
disorder of visual integration
due to lesions upstream from the striate cortex
undetermined disorders of visual integration
disorders not easily classified in the two former categories
cone dystrophy
genetic defect that causes malformation of the cones, slow progressive loss of central vision
cone dystrophy symptoms
vision during daytime, photophobia, problems detecting colors, problems with sharp VA
what type of ocular bleeding affects vision
macular
homonymous
same-side visual field defect
heteronomous
opposite-side visual field defect
hemianopsia
absence of hemifield of vision
quadrantanopsia
abscence of a quadrant of vision
absolute scotoma
deep, no response to light in that area no matter how bright the stimulus
relative scotoma
area of depressed vision, responds to light but may need brighter stimulus to do so
is visual field monocular or binocular?
it’s both
optic chiasm lesion
bitemporal or binasal hemianopsia
optic tract lesion
loss of contralateral field right or left hemianopsia
optic radiation lesion
quadrantopsia
primary visual cortex lesion
typically congruous, either hemianopsia or quadrantopsia (macular sparring)
hemi-inattention, hemi-neglect
inability to draw half of an object
spatial neglect
inability to copy an image fully
ventral disorders
visual object agnosia, prosopagnosia, achromatopsia
dorsal disorders
optic ataxia, ocular apraxia, simultanagnosia, constructional apraxia, akinotopsia
primary visual sequelae of acquired brain injury
post-trauma vision disorder, midline shift, convergence insufficiency, processing speed, photophobia
ischemic stroke
interruption of blood flow to brain
visual effects of stroke
visual field defects, agnosias, neglect, cortical blindness, binocular and accommodative problems
prosopagnosia
face blindness
- posterior commissure artery infarct
- fusiform gyrus
visual discrimination
difficulty indistinguishing one item from another, confusing or misunderstanding written symbols
visual sequencing
inability to see and distinguish the order of symbols, words, or images
visual motor processing
inability to use feedback from eyes to coordinate the movement of other parts of the body
visual closure issues
difficulty in identifying an object when only parts are visible
dyscalculia
difficulties with calculation and number concepts
dyslexia
difficulty with reading, writing, spelling word recognition and sequencing
dyspraxia/DCD
difficulties with planning movements, co-ordindination, and practical tasks as well as tracking and balance, poor spatial awareness and muscle tone
Autistic spectrum disorder (including asperger’s syndrome)
social and communication problems, obsessive, difference of imagination
