Experience

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Experience Visual Development

• Testing Method Preferential looking
• Normal Acuity and Contrast Sensitivity
  Development
• Acuity Development After Cataract Removal
• Implications For Mechanisms of Normal Acuity
  Development

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Preferential Looking
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Spatial Frequency
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Contrast Sensitivity
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Acuity Development
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Contrast Sensitivity Infants vs. Adults
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Testing Methods Normal Perceptual Development

• Preferential looking and the tester guesser
• Spatial frequency and acuity
• Normal changes with age in grating acuity
• Contrast Differences
• Normal changes with age in contrast sensitivity
  and acuity

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Why Does Early Vision Improve?

• Changes in the eye during infancy
• Such as increases in cone density
• Cannot account for all acuity improvement
• Using a mathematical model (Ch. 16)gt
• Changes in the brain must contribute

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A Child with a Congenital Cataract
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Testing Methods Normal Perceptual Development

• Preferential looking and the tester guesser
• Spatial frequency and acuity
• Normal changes with age in grating acuity
• Contrast Differences
• Normal changes with age in contrast sensitivity
  and acuity

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Acuity Development After Cataract Removal

• Method Longitudinal Study of Congenital vs.
  Developmental Cataract Removal Acuity
• Immediate vs. long-term effects
• Patching effects

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Acuity Before vs. After Developmental Cataract
Removal
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Short Term Acuity Development After Congenital
Cataract Removal

• One week after operation bandages are removed and
  
• Immediate acuity measurednewborn
• Measured again one hour later
• Improvementgt
• Initially brain stimulation improves acuity

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Long-Term Acuity Development After Congenital
Cataract Removal

• Patients almost never achieve normal levels of
  acuity
• Five years after cataract removal
• Even with patching of non-deprived eyegt
• Later acuity depends on competition and
• Non-deprived eye got an initial brain advantage
  that it never lost

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