Development of Binocular Vision Flashcards
the ability of the brain to change as a result of experience
Plasticity
examples of plasticity in negative consequences
phantom pain, addictions, trauma, poor binocular vision
Limited time during which the nervous system displays heightened sensitivity to environmental stimuli. If the organism doesn’t receive the appropriate stimulation during this time window, it may be difficult, if not impossible, to develop certain functions later in life.
Sensitive periods aka “Critical periods”
Examples of sensitive periods
Imprinting
Binocular vision
birdsong
language
Order of sensitive periods
Seeing and hearing/visual & auditory cortex (first)
Receptive language/ speech production / angular gyrus, broca area
Higher cognitive functions/prefrontal cortex (last)
Do functions dependent on retinal neuron development have earlier or later critical period?
Earlier critical period
What takes the longest time to develop in vision? What does this make them vulnerable to?
Spatial and binocular vision. Makes them most vulnerable to effects of abnormal inputs.
What are the two earliest critical periods for visual functions in humans?
Absolute light detection and temporal resolution
What area does the Sweep VECP evaluate? What does it test?
cortical area V1
tets monocular and binocular visual functions to see if brain received signal
What kind of technique is forced-choice preferential looking?
Behavioral technique
What kind of response has to do with a looming target?
Avoidance response
When does a baby have reasonably accurate accommodation?
3-5 months
What direction does early smooth pursuits and OKN develop?
temporal visual field to nasal visual field
Nasal retina to temporal retina
What matures faster? Accurate convergence or divergence?
convergence matures quicker
During a visual cliff test, when would the child avoid the “deep side” of the cliff?
6-8 weeks
What develops first? Fine stereoacuity or fine monocular spatial resolution?
Fine stereoacuity
When do fusion and binocular summation develop?
3-5 months after birth
When does the LGN segregate into its layers?
3-5 months gestation
What develops first? Contralateral or Ipsilateral layers?
Contralateral layers
In the V1, what happens within the first 10 months of postnatal?
Dramatic increase in cortical volume
Dramatic increase in synaptic density
In the V1, what happens from 10 months to approximately 8-10 years?
Gradual decrease in cortical volume
Gradual decrease in synaptic density
Increased specificity of remaining synapses.
What are the 2 phases of resolution visual acuity development?
Very rapidly within the first several postnatal months
Very gradually during the subsequent decade
What is Hebb’s rule?
Connections synchronously active = strengthened
Connections not synchronously active = weakened
Amblyopia criteria
Acuity must be less than 20/40 to be defined as amblyopia, AND
there must be at least 2 lines’ difference in the Snellen acuity between the two eyes.
