Chapter 24 - Evaluation And Treatment Of Visual Deficits After Brain Injury Flashcards
Ability to manipulate, visual input and integrate vision with other sensory info to gain knowledge, solve problems, formulate plans, and make decisions.
Visual cognition
Pattern recognition cannot be accomplished without what next process?
Visual scanning
Visual cognition cannot occur without the support of?
Visual memory
Mental manipulation of visual input requires the ability to create, retrain, and recall memories of images to use for comparison during visual analysis.
Visual memory
To store and access images in memory, the person must recognize?
The pattern making up the image
What is organized scanning of the visual array also called?
Visual scanning
Visual scanning or search is actually an expression of?
Visual attention
Visual search occurs on what two levels?
Reflexive/automatic level and voluntary level
A person who does not attend to visual information will not be able to do what?
Anything prior to visual attention.. such as unable to initiate search for visual information, not be able to determine pattern recognition, or use visual memory
What are the 3 primary visual functions that ensure the brain receives high quality visual input?
Oculomotor control, visual field, visual acuity
Enables eye movement to be completed quickly and accurately and keeps the image focused on the fovea to ensure it can be clearly seen
Oculomotor control
If brain injury impairs a lower level process or function is the process above or below compromised?
Above
What are the two most vision dependent daily activities?
Reading and driving
Example for increasing the contrast of key components of the task and environment
- Using a black cup for milk and white cup for coffee.
- Color can be added to the object when color cannot be changed. (Adding a bright strip with stairs)
Examples of reducing or eliminating any background pattern
Using solid colors on backgrounds surfaces such as bedspreads, place mates, etc can increase the visibility of objects placed on them
Example of enlarge critical features of objects and environments
Increasing the size of a feature or object
Increasing the text size
Contrast should be considered and changed if needed
Example of providing adequate and good quality illumination
- Lightning should be strategically placed to provide illumination
Good acuity facilitates..
Information processing and decision making
How is visual acuity measured?
Person identifying progressively smaller optotypes on a chart at a specific distance.
Hyperopia is also called? And what does it cause?
Farsightedness and causes for objects to be blurry when near the retina
Myopia is also called? And what does it cause?
Nearsightedness and causes for objects to appear blurry when far away from retina
What are the three most common optical defects affecting acuity?
Myopia, astigmatism, hyperopia
Astigmatism causes what? And at what distance?
Causes blurry vision at close or far distance
Damage to the central retina diminishes?
Both high and low contrast visual acuity, impairing accurate identification of objects
Two eye diseases that damage the photoreceptor cells in the central visual field
Age related macular degeneration and diabetic retinopathy
What is the most common cause of optic nerve damage in brain injury?
Trauma
What are the two common neurologic disease that damage the optic nerve?
Glaucoma and optic neuritis
Neurologic disease that affects the peripheral visual field first and may progress into the central field, reducing visual acuity
Glaucoma
Neurologic disease that can cause reduced visual acuity and color vision, visual field deficit, orbital pain, dulled vision, and sensitivity to light
Optic neuritis
Optic neuritis is also found in what other neurological disease?
Multiple sclerosis
Damage to posterior cortical processing causes what?
Blurred vision, reduced contrast sensitivity, a perception of dark or dim vision, light sensitivity, and reduced dark adaption.
Central field impairment affect?
The ability to discriminate small visual details and to distinguish contrast and color
Peripheral field deficits impair?
The ability to locate landmarks and obstacles, accurately detect motion, and maintain orientation in the environment.
Which field impairment affect a persons mobility? Central field or peripheral field?
Peripheral field
What is the purpose of Oculomotor function?
Purpose is to achieve and maintain foveation of an object
Another function of Oculomotor?
Provide binocular vision
What is the process of combining two visual images into one?
Sensory fusion
In paralytic strabismus the eye is affected how?
Unable to move in the direction of the paretic muscles which distrusts the ability of the eyes must always move together
What is a primary characteristic of CN lesions?
Diplopia
What does diplopia creates?
Creates a perceptual distortion ad performance limitations
Most common identified focusing disorder is?
Convergence insufficiency
What occurs with convergence insufficiency?
Client have difficult obtaining or sustaining adequate focus during near vision tasks. Complain of fatigue, pain, or headache.
Oculomotor impairments also occur in what other neurological diseases?
Parkinson’s, MS, Alzheimer
