sped 537 ecse methods multiple disabilities chapter 4
Download
Skip this Video
Download Presentation
SPED 537 ECSE Methods Multiple Disabilities Chapter 4

Loading in 2 Seconds...

play fullscreen
1 / 18

SPED 537 ECSE Methods Multiple Disabilities Chapter 4 - PowerPoint PPT Presentation


  • 118 Views
  • Uploaded on

SPED 537 ECSE Methods Multiple Disabilities Chapter 4. March 13-14, 2006 Deborah Chen, Ph.D. CSU, Northridge. Incidence of Visual Impairments. 1 in 3000 children 46\% congenital 38\% vision loss in 1 st year of life 25 \% totally blind 25 \% light perception 50\% functional vision.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'SPED 537 ECSE Methods Multiple Disabilities Chapter 4' - delu


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
sped 537 ecse methods multiple disabilities chapter 4

SPED 537 ECSE Methods Multiple DisabilitiesChapter 4

March 13-14, 2006

Deborah Chen, Ph.D.

CSU, Northridge

incidence of visual impairments
Incidence of Visual Impairments
  • 1 in 3000 children
  • 46% congenital
  • 38% vision loss in 1st year of life
  • 25 % totally blind
  • 25 % light perception
  • 50% functional vision
definitions
Definitions
  • Legally blind
  • Totally blind
  • Light perception
  • Form perception
  • Partially sighted
  • Low vision
types of visual impairment
Types of Visual Impairment
  • Decreased visual acuity
  • Field loss
  • Loss of contrast sensitivity
  • Color blindness
  • Ocular-motor problems
  • Cortical visual impairment
  • Delayed visual maturation
causes of acuity loss
Causes of Acuity Loss
  • Retinopathy of Prematurity
  • Cataracts
  • Nystagmus
  • Refractive errors
  • Strabismus
refractive errors
Refractive Errors
  • Myopia
  • Hyperopia
  • Astigmatism
strabismus
Strabismus
  • Esotropia
  • Exotropia
  • Hypertropia
  • Hypotropia
clinical vision tests fixation and eye alignment
Clinical Vision Tests: Fixationand Eye Alignment
  • Versions
  • Hirshberg
  • Krimsky
  • Unilateral and alternating cover test
  • Base-out prism
clinical vision tests
Clinical Vision Tests
  • Pupillary response
  • Vestibular ocular reflex (VOR)- similar to Optokinetic Nystagmus (OKN) test
  • Refractive Error
behavioral tests
Behavioral Tests
  • Contrast sensitivity
  • Color vision
  • Depth perception
  • Visual fields
  • Visual acuity (Teller Cards)
electrophysiological tests
Electrophysiological Tests
  • Visual Evoked Potential (VEP) or Visual Evoked Response (VER)
  • Electroretinography (ERG)
checking for ocular health

Checking for Ocular Health

Examines the front and back structures, retinal, optic nerve

ocular visual impairment
Ocular Visual Impairment
  • Atypical eye exam
  • Consistent visual attention
  • Nystagmus
  • Restrictions of visual fields
  • Occasional photophobia
  • Eye pressing
  • Occasional head shaking
  • Light gazing
cortical visual impairment
Cortical Visual Impairment
  • Normal eye exam
  • Variable vision
  • Short visual attention
  • No nystagmus
  • No head shaking
  • No eye pressing
  • Light gazing
  • Photophobia in 1/3 cases

( Dr. J. Jan, Children’s Hospital, Vancouver, B.C. Canada)

visual responses
Visual Responses

Awareness Attention Understanding

Fixation Tracking

Peripheral Central

Simple Complex

visual responses1
Visual Responses

Awareness Attention Understanding

Large Small

Familiar Unfamiliar

Near Far

visual stimuli
Visual Stimuli
  • Preferred:
    • Objects with lights or movement
    • Geometric designs
    • High contrast materials
    • Bright colors
  • Familiar:
    • Family members
    • Clothing, utensils, household items
    • Toys
    • Pictures
visual saliency
Visual Saliency
  • Motivation factors
  • Lighting (natural, indoor, outdoor, dark)
  • Position (placement of target)
  • Distance from child
  • Highlight or contrast
  • Illumination of target
  • Characteristics of target
ad