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AUTISTIC SPECTRUM DISORDERS
AND CORTICAL VISUAL IMPAIRMENT:
TWO WORLDS ON PARALLEL COURSES
AER/DENVER - JULY, 2000
MARY T. MORSE, Ph.D.
Education Consultant for Children With Special Needs
247 Pembroke Hill Road Pembroke, NH 03275
Phone (603) 485-7674
Fax (603)-485-1958
mary@seresc.net
CORTICAL VISUAL IMPAIRMENT (CVI)
Cortical Visual Impairment (CVI) is a disability resulting from either an
insult to the brain or how the brain organization became configured during
prenatal development. CVI effects how an individual
understands the visual information received by the eyes. The location and extent
of the brain insult determines which functional behaviors will be effected.
For those who show some visual responses during infancy, the prognosis for
increased functional use of vision is good. Indeed, many (not all) may use
vision as their primary information gathering sensory modality when they are
older.
Commonly Known General Characteristics of CVI Include
- Wide variations in functional use of vision: Some individuals demonstrate
no visual responses at any times while other individuals have considerable
use of vision
- Wide variability in an individual's ability to efficiently use vision on
a consistent basis.
- Wide variation in regard to additional disabilities which may/may
not include other ocular handicaps, medical and health problems,
seizures, hearing, communication, self care skills, feeding, cognition,
type of visual and auditory stimuli understood, interpersonal relationships,
learning, etc.
- Wide variability within individual persons and between individuals in managing
multi-sensory demands and planning/implementing motor responses
- Tendency to use peripheral vision more than central vision
- Possible depth perception difficulties
- Tendency to look away when reaching
- Tendency to have associated central auditory processing problems
- may be very interested in sounds
- may give the appearance of understanding all they hear
- may be particularly responsive to intonations rather than actual words
Characteristics of CVI Not Commonly Addressed
Some individuals with CVI do not have obvious additional
disabilities. These individuals may be able to walk, care for themselves, talk,
and have excellent visual behaviors for some types of stimuli. However, they
may have visually-based difficulties with specific stimuli and skills that
are of neurological origin. These individuals may have difficulty
or the inability
- to recognize objects in general or specific categories of objects - especially
stationary objects
- to recognize and discriminate one human face from another (Remember: All
faces have eyes, ears, nose & mouth and, thus, are structurally the same.)
- to recognize a human face as more than an object unless it moves or talks.
- to organize oneself spatially
- to comfortably move through even a very familiar environment
- to recognize and use visual symbols which may include print, photographs
and/or line drawings
- to recognize colors
- to point to various parts of their own body
- to distinguish left from right.
Prosopagnosia and Facial Agnosia
A particular sub-set of individuals with CVI may have difficulty or the inability
to recognize familiar faces (Prosopagnosia) or difficulty
or inability to recognize any face, familiar or not (Facial Agnosia).
Processing the human face is an extraordinarily complex visual,neurological,
social, and communicative process. These individuals may have several of the
following characteristics:
- May have different neurological sources causing the condition.
- May have variations between persons in brain imaging results.
- Will show variations even within this sub-group of persons with CVI. For
example, may/may not have associated agnosias (not recognize objects and/or
certain categories of objects and/or two dimensional visual representations
and/or certain categories of two dimensional visual representations).
- May avoid visually fixating on the human face OR
- May stare intently at the human face OR
- May look toward only one part of the face (i.e., mouth) rather than the
facial configuration
- May be able to name and/or point to various parts of the face but not
recognize and identify the total configuration.
- May recognize some faces from one orientation, within context, but not
be able to generalize that face to other orientations or situations.
- May want to touch people - especially their faces
- May not realize that they differ from others in recognizing faces
- May not understand totality of language but brighten considerably when
language is combined with emphasized intonation.
- May understand language but have difficulty in using pronouns
- May use language but tend, at times, to "talk to the air"
- May have difficulty in discriminating one voice from another
- May have excellent short term auditory memory
- May not realize a person is present unless the person says something or
moves
- May focus on a specific aspect of a person for identification (if they
realize person is present)
- May treat people as objects
- May have difficulty relating to peers
- May appear to prefer objects to people
- May have "subtle" additional disabilities such as fine and gross
motor dyspraxia, social interactions, pragmatics of language, behavior, spatial
disorganization
- May show definite ability to learn - especially colors, shapes, repeating
alphabet, etc.
- May/may not have difficulty interpreting some/all types of two dimensional
visual representation (very variable)
- Some may be able to recognize pictorial representations of faces but not
be able to do so with tangible face
- May have difficulty managing multiple sensory-motor demands - frequently
said to have sensory integration problems
- May have difficulty modulating their states of arousal.
- Frequently said to be inattentive and distractible - sometimes labeled
ADHD, PDD, autistic
- Perceptual impairments usually are an insufficient explanation for face-specific
agnosia
- For many of the children, however, vision is their primary information
gathering sensory modality
- Individuals who have the condition from birth may function better with
the condition than those adults who suddenly acquire the condition due to
some insult.
Some Diagnostic Strategies
- What is the visual diagnosis?
- What is the cause (etiology) of the condition?
- Have any types of brain imaging procedures been done?
- Parent reporting
- School reporting
- Systematic Observations
An Initial Reading List To Begin The Process of Understanding
Bolles, E. A Second Way of Knowing: The Riddle of Human Perception.
NY, NY: Prentice Hall Press. 1991.
Buxbaum, L., Glosser, G., & Coslett, H. (1999). Impaired face and word
recognition without object agnosia. Neuropsychologia, 37, 41-50.
Bruce, V. & Humphreys, G. (1997). Object and face recognition. Journal
Visual Cognition - Special Issue. England: Taylor & Francis Publishers.
Choisser, B. Face Blind- an online book. www.choisser.com/faceblind/about.html.
Damasio, A., Damasio, H., & Van Hoesen, G. (1982). Prosopagnosia: Anatomic
basis and behavioral mechanisms. Neurology, 32, 331-342.
Dennis, M., Kaplan, E., Posner, M., et al. Clinical Neuropsychology and
brain function. Hyattsville, MD: American Psychological Association,
Inc. 1989.
Dutton, G., Day, R. & McCulloch, D. (1999). Who is a visually impaired
child? A model is needed to address this question for children with cerebral
visual impairment. Developmental Medicine & Child Neurology, 41,
211-213.
Farah, M. Visual Agnosia: Disorders of Object Recognition and What They
Tell Us about Normal Vision . MIT Press, Bradford Books. 1990.
Fery, P. (1997). Associative visual agnosia without perceptual impairment:
A case study. Online pfery@ulb.ac.be.
Gauthier, I, Behrmann, M. & Tarr, M. (1999). Can face recognition really
be dissociated from object recognition. Journal of cognitive neuroscience,
11, 349-385.
Humphreys, G. To See But Not to See: A Case Study of Visual Agnosia.
England: Taylor & Francis Publishers. 128 pages. 1987
Jambaque, I., Motron, L., Ponsot, G., & Chiron, C. (1998). Autism and
visual agnosia in a child with right occipital lobectomy. J Neurol Neurosurg
Psychiatry, 4 , 555-60.
Jan, J. & Freeman, R (1998). Who is a visually impaired child? Developmental
Medicine & Child Neurology, 40, 65-67.
Klin, A., Sparrow, S., de Bildt, A., et al (1999). A normed study of face
recognition in autism and related disorders. Journal of autism and developmental
disorder, 29, 499-508.
Morse, M. (Spring, 1999). Cortical visual impairment: Some words of caution. RE:view , 31, 21-26.
Morse, M. (1992). Augmenting assessment procedures for children who have severe
and multiple handicaps in addition to sensory impairments. Journal of Visual
Impairment and Blindness, 86, 73-77.
Morse, M. (1991). Visual gaze behaviors: Considerations in working with multiply
handicapped/visually impaired children. RE:view, XXIII, 5-15.
Morse, M. (1990). Cortical visual impairment in young children with multiple
disabilities. Journal of Visual Impairment and Blindness, 84, 200-203.
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