Week 4 Flashcards
True or false: newborns see well enough to perceive “faces”
True, Johnson et al. (1991) found that a paddle with a schematic of a face as opposed to blank/scrambled caused infants to turn their heads more often to it
Define acuity
perceiving fine detail
What is the adult snellen test
eye test used for adults with rows of letters progressively getting smaller in size further down to test acuity
Testing visual acuity in infants: what is reflexive following? (optokinetic nystagmus)
little gradings (lines) move back and forth where the test is to see if infants follow it (you can modify the sharpness of the gradings)
Testing visual acuity in infants: what is visual paired comparison?
-uses two stimuli e.g. grey circle and lined circle to see how much detail the infants perceive/prefer
What are babies clinical vision like from newborn-8 months?
NB-20/660 (what adults could see 660 ft away, babies would need to see 20)
2 mos-20/300
8 mos-adultlike vision
How does acuity improve for infants?
-develops over the first few years of their life
-improvements in perceiving high spatial frequency (fewer spaces between lines e.g.) and low contrast info (not the contrast of black and white as strong more grey e.g.)
How does the case study of Virgil demonstrate that visual development is dependent on visual experience?
-Sacks (1995) said virgil was a man with dense cataracts since childhood potentially always having poor vision
-got them removed when he was middle-aged
-still unable to interpret much even if the visual stimulation became available to him demonstrating we “learn to see” (didn’t get chance to learn much due to cataracts blocking portion of light into eye)
Which area is our vision most acute?
the fovea
What’s the job of the lens?
to bend the light to focus on the retina (including the fovea)= accomodation
Why is it important to remove the cataract as early as possible?
-by removing the cataract and inserting a lens it gives a better opportunity for the eye to connect/transmit visual input to the brain
-the normal eyes connections get stronger and stronger through experience whereas the cataract eyes connections will get weaker and weaker due to lack of usage if not removed to force the connections to become useful
-plasticity occurs
True or false: corrected cataracts result in small deficits in face perception (using configural information ) as adults (LeGrand et al., 2001)
True the corrected eye will not be on par to the normal healthy eye most times
-people with corrected cataract can recognise different features just aswell as people who had no cataract but poor in recognising configurated faces (same internal state but different arrangements)
True or false: changes in visual acuity aren’t strongly dependent on experience.
false changes in visual acuity (plus face perception/recognition) ARE strongly dependent on experience
How do infants interpret info about objects perceived in the environment?
-they’re biased to attend to the contours of high contrast e.g. edges of an object (helpful perceiving its outline)
-they perceive things as coherent entities aka object unity
What did Spelke find in relation to infants distinguishing an object from its background?
-3 mos look longer at “impossible” event (part of an object moves with background) than a “possible” event (object moves separate from background)
-3 mos look longer at “impossible” event (grasping part of an object results in only part of it moving like a chunk) than to a “possible” event (entire object moves when grasped)
How do infants perceive partially occluded objects according to Kellman & Spelke (1983)?
A partly covered rod moves behind a stationary box
* After habituation (diminishing of innate response), 4-month-old infants longer at the broken rod (i.e. perceive object unity),
but ONLY if the rod is moving
* Newborns look longer at the complete rod. (innate response)