Injuries & Diseases Impact Vison and Visual Perception Flashcards
blurs the sharp, central vision needed to see straight ahead. Impact the macular, decreases acuity. Wet and dry forms
Wet – abnormal blood vessels grow behind macula causing leakage; causes central vision loss
Dry – macula thins over time gradually blurring central vision
Macular Degeneration
leading cause of blindness American Adults, progressive damage to blood vessels of retina. Usually bilateral impact, 4 progressive stages.
Diabetic Retinopathy
Clouding of the eye’s lens, causes loss of central vision, blurry or wavy areas in central vision. Leading cause blindness worldwide. Surgical removal.
Cataract
Loss of central vision, blurry or wavy areas in central vision. Group of disease that can damage optic nerve. Occurs when normal fluid pressure in eye (10 to 20 mmHg). Generally over 21mmHg diagnostic
Glaucoma
aka “lazy eye”, most common visual impairment in children. Eye and brain are not working together, brain “favors” one eye
Amblyopia
cross-eyed, lack of coordination between two eyes & optic nerve. Impacts both eyes. Causes eyes to struggle to focus on same point, irises appear to be looking two different directions.
Strabismus
extracellular deposits of lipids, proteins & cellular debris. Found in layers of retina. Appear as small yellow deposits. Occur with other conditions
Drusen
floaters, spots and/or flashes cross field of vision. Most commonly cloudy or semitransparent vitreous particles
Floaters and spots
near-sightedness (near is clear)
Refractive error
Myopia
far-sightedness
Refractive error
hyperopia
loss ability to up close, occurs between
40 – 50 yrs. age
presbyopia
distorted vision at all distances
astigmatism
difficulty see difference between similar letters, shapes, objects
Visual discrimination
Struggle to distinguish shape from backgrounds
visual figure ground discrimination
Struggle to see items, letters in correct order
visual sequencing
to use what they see to coordinate how they move, bump into objects, struggle to stay in the lines
visual-motor processing issues
struggle to remember shapes, symbols or objects seen, not replicated in auditory memory.
long/short-term visual memory
struggle identify where objects are in space
visual spatial issues
Switch numbers & letters when writing or may mistake visually similar letters b/d, m/w.
letter and symbol reversal issues
Difficulty identifying an object when only parts of the object are showing
visual closure issues
neurological disorder characterized by inability to recognize and identify objects or persons using one or more of the senses.
Caused by damage to parietal, temporal or occipital lobes. Areas important for memories of function, importance of objects, sight
agnosia
Wat are the types of agnosia?
- Appreciative
- Associative
- Prosopagnosia
- Topographic Disorientation
- Pure Alexia
unable to recognize an object, even if they can describe object by size, shape texture.. Impairment is to object perception
Generally do better with real object vs picture and even better with movement/pantomime vs static picture
Appreciative Agnosia
subtype of visual agnosia – perception intact impairment is to the association of the precept with meaning, difficulty understanding the meaning of what they are seeing. Able to draw or copy the object but do not know what it is
Associative Agnosia
inability to recognize faces, aka face blindness. Believed to be related to damage to right fusiform gyrus
Prosopagnosia
Acquired inability to navigate the environment in daily life. “Memory deficit in visual realm”
Lesion in medial occipitotemporal area
Topographic Disorientation
alexia without agraphia – acquired reading disorder, unable to read despite preservation of other aspects of language including spelling and writing. Associated with occlusion distal branches of left posterior cerebral artery.
Pure Alexia
