Visual Experience Flashcards
How is visual acuity at birth?
20/800.
How do preferential looking tasks work?
Infants prefer to look ya more complex or novel images and the direction of their gaze can be recorded.
How does habituation work?
Infants look less at familiar than novel objects and the duration and frequency of their looking can be recorded.
What does habituation test?
Ability to recognise and remember.
Give an advantage of the visual cliff paradigm.
It is quite natural.
Give 2 disadvantages of the visual cliff paradigm.
It is not well constrained and can only use infants who can crawl, so innateness is questionable.
What do Zanker we al (1992) suggest about the different improvement rate of infants at vernier and grating acuity?
Different mechanisms are used for these different tasks and there is a role of experience.
At 2 weeks, infants prefer an image of the (contrast/features) of a face.
Contrast.
At 6 weeks, infants prefer an image of the (contrast/features) of a face.
Features.
Infants younger than 3 months olds are (better/worse) than adults at discriminating sheep and monkey faces.
Better.
Briefly describe amblyopia.
Poor visual acuity and other deficits that cannot be improved with optical correction.
Why is amblyopia often linked to an imbalance between the eyes?
If one eye is better than the other, people tend to suppress the input from their ‘bad’ eye.
How did a more recent study suggest that infants cannot consistently imitate?
By measuring the probability of infants making the same facial action as 10 other actions in a fixed time, revealing that they do certain things no matter what they are shown.
Provide evidence for a role of experience in face processing.
Infants looked at female faces 64% more, but 59% of infants with a male primary caregiver preferred male faces.
What is the critical period for normal development of vision?
The first few years of life.
Give 2 reasons why there must be a role for visual experience in visual development.
To deal with physical changes and to tube to the local environment and calibrate.
What is essential for cells with binocular receptive fields to develop?
Both eyes must be open during development.
What does even a few hours in a ‘vertical’ rearing environment do?
Biases V1 cell orientation tuning.
What is a common treatment for amblyopia?
Patching of the unaffected eye during the critical period before age 7.
What abilities are present when people recover from blindness?
Figure (ground segregation and colour), shape from shading and motion perception.
What abilities are absent when people recover from blindness?
Depth, perspective, illusory contours and contour integration.
Give 3 problems in interpretation of studies on recovery from blindness.
Experience before blindness is untested, adults knowledge is used in interpreting vision and degeneration of the visual system is not accounted for.
Define perceptual learning.
A change of perception as a result of experience.
What is stimulus onset asynchrony?
The time different between the appearance of a mask and a target.
Why is investigating transfer of perceptual learning important?
If learning does transfer, this could be important for vision treatment and whether or not transfer occurs suggests where learning is occurring and the neural correlates of learning.
(Specificity/transfer) of perceptual learning suggests early cortical processing.
Specificity.
(Specificity/transfer) of perceptual learning suggests higher level processing.
Transfer.
In what type of task can amblyopia show a broader range of improvement than controls?
Contrast sensitivity.
Summarise the findings of a video game and amblyopia cross over study.
All games improved several function, such as acuity, (but particularly action games) and the occlusion path had no effect.
