Download PaTTAN CVI COP Book Study Webinar Series Guided Notes

CVI COP session 1 book study guided notes
PaTTAN CVI COP Book Study Webinar Series Guided Notes
Session 1: Sept. 25, 2012 3:00 – 4:30 PM
COMMUNITY OF PRACTICE BOOK STUDY MATERIAL:
Cortical Visual Impairment – An Approach to Assessment and Intervention
GOALS OF SESSION 1: Provide an overview of guiding principles, the diagnostic process,
and incidence of CVI
INSTRUCTIONS:
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Briefly review Foreword, Preface, Acknowledgements, and My Introduction to CVI (pp.
vi-xi; pp. 1-4)
Carefully read Chapter 1 - Overview of CVI (pp. 5-10).
Complete the Guided Notes and Timeline before the webinar session. Highlight the word
blank between the angle brackets (<blank>) to insert answers.
GUIDED NOTES:
1. Definition and Description of CVI:
Cortical visual impairment (CVI) is not the same as <blank> forms of visual impairment.
(“Ocular” refers to the eye, including the eye muscles). Instead of ocular forms of visual
impairment, CVI exists because of problems with the visual processing centers and visual
pathways of the brain (Jan & Groenveld, 1993, in Roman-Lantzy, 2007).
CVI is a term used to describe visual impairment that occurs because of <blank>
<blank>
CVI includes a significant lack of visual function or lack of visual responsiveness. The eye
exam will be <blank><blank> or near <blank>. Neuroimaging, such as magnetic resonance
imaging (MRI) and computerized axial tomography (CAT) may show damage to parts of the
brain associated with visual <blank> (e.g., visual cortex, optic radiations).
An <blank> <blank> alone cannot explain the lack of visual functioning.
2. Terminology:
We will use the term “cortical visual impairment.” This is most commonly used in the
<blank> . (The term “cerebral visual impairment” is more commonly used in Europe).
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CVI COP session 1 book study guided notes
3. Putting CVI into a Historical Perspective:
Our understanding of the brain, and the application of that information to CVI, has evolved. See
Figure 1.1: Visual Pathways and the Brain on page 7. The <blank> of the cerebral cortex at the
back of the brain are primarily concerned with vision.
Supplemental Information: The cerebral cortex, which comprises 80% of the human brain, is a 1
to 3 millimeter layer that wraps the surface of the brain, similar to bark on a tree. There are
many grooves and fissures in the cortex, and if smoothed out, it would be about 2 square feet.
The complexity of brain function increases with cortical area. It is the complexity of the cerebral
cortex that allows us to perceive, to think, to use language, and other functions (Sternberg,
2009).
Visual messages from the eye, traveling along the <blank> nerve, are routed to the occipital
lobes of the cerebral cortex at the back of the brain. The visual message is analyzed by millions
of cells for elements such as <blank> , <blank> , and <blank>.
After the message is processed and reconstructed in the occipital lobe, it is sent to the temporal
and parietal lobes of the brain. The parietal lobe integrates the image with other sensory input to
help in <blank> of the image.
Supplemental information: While not discussed in Chapter 1, the temporal lobe primarily is
primarily associated with auditory functions. It is also a primary center for retention of visual
memories (Sternberg, 2009).
Visual cortex <blank> are strictly organized, and sequentially analyze and interpret each aspect
of an image.
There is a precise and organized way in which specific cortical areas process details.
Timeline: (see Figure 1: Timeline, for a graphic display of events).
1600s: Belief that areas of the brain are specific to <blank> .
Early 1800s: Belief that vision is regulated by specific areas of the visual <blank>.
Mid 1800s: Discovery that occipital cortex is the <blank> for visual functions.
Early 1900s: Discovery that <blank>in the occipital cortex resulted in scotomas.
The term “cortical blindness” emerged to describe temporary or permanent loss of vision in
<blank> who had experienced loss of oxygen, disease, or trauma.
1970s: Major discoveries about the period of plasticity for visual development, which is most
pronounced between birth and the age of <blank> years.
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CVI COP session 1 book study guided notes
1980s: Additional findings about plasticity and critical phases for visual development were
published.
Brain damage as a possible cause of visual impairment in <blank> was recognized.
4. Critical Period of Visual Development:
Hubel and Weisel (1970) conducted animal research that involved visual deprivation. Their
research showed that <blank> during critical periods of visual development resulted in
<blank><blank> vision loss.
The development of vision is dependent on the ocular system and also upon exposure to stimuli
in the <blank>. Specific visual functions are activated by corresponding
<blank>. E.g., the ability to see <blank> develops “… as the infant looks at the movement of
people, crib mobiles, and manual gestures” (Roman-Lantzy, 2007, p. 8). The ability to see
<blank> develops as the child is exposed to objects with patterned surfaces.
The most important time for meaningful experiences with visual stimuli is in <blank>.
Therefore, infants with brain injury should be screened as early as possible for potential vision
impairment associated with <blank>.
5. Importance of Early Intervention:
<blank> affect patterns of connections in the cortex. Delays in early diagnosis and appropriate
intervention may result in lost opportunities for learning. The <blank>, the better!
Prompt <blank>, careful <blank>, and planned <blank> can facilitate visual functioning.
This has a long-term effect on every area of learning and development.
6. Incidence of CVI:
<blank> is the leading cause of visual impairment in children in industrialized countries.
Reasons associated with the incidence of CVI include increased <blank>of low-birth weight
and premature infants, and other advances in medicine. Younger and more fragile infants have a
higher chance of <blank> impairment.
GUIDING PRINCIPLES:
There are eight guiding principles that provide an overview of the book. As we proceed through
the chapters, the related guiding principles will be featured.
Guiding Principle #1:
“CVI is best identified and diagnosed by
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CVI COP session 1 book study guided notes
A <blank> eye exam or an eye exam that cannot explain the profound lack of functional vision
A medical history that includes <blank> problems
The presence of unique visual and behavioral characteristics” (Roman-Lantzy, 2007, p. 3).
Guiding Principle #3:
“In infants with CVI:
Visual function improves or declines but rarely remains static.
Vision can be rehabilitated with permanent increased function during the critical window of
visual <blank> in the period of infancy.
Progress and permanency of visual function depends on <blank> and <blank> support”
(Roman-Lantzy, 2007, p. 3).
ADDITIONAL RESOURCES:
American Foundation for the Blind: Web Page on “Cortical Visual Impairment, Traumatic Brain
Injury, and Neurological Vision Loss:
http://www.afb.org/section.aspx?FolderID=2&SectionID=93&TopicID=417
COMMENTS AND QUESTIONS:
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