Week Four - Perceptual Development Flashcards
What was John Locke’s view on newborns sensation?
Newborns mind is like a white page where all ideas and abilities are developed through learning and experience
What did William James propose about newborns sensation?
That babies cannot distinguish between sensations
What is today’s view on infants sensation?
Infants are born with many skills and actively learn many more, rapidly, as they explore
What is sensation?
detection and discrimination of sensory information
What is perception
Interpretation of those sensations including recognition and identification
What is the most important sense?
Vision
- takes up nearly half of the cerebral cortex and improves over first months of life
What are some popular testing methods for vision?
Preferential looking task
Habituation
Conditioned head-turn
What is preferential looking task assessing?
Whether the infant can discriminate between two similar visual stimuli (looking time is measured)
What is habituation?
A gradual decrease in response to interest in a repeated stimulus
What is novelty preference?
Human preference for anything new or different
Why is habituation useful?
Means we won’t continuously notice things that are there all the time and don’t need our attention
What do infants lack at birth?
Visual acuity but improves during first month (nd better when tracking/scanning)
What age is visual acuity in infants adult level?
6 months
How do we test visual acuitty?
Preferential looking (narrow stripes over plain)
Colour vision in infants?
Initially limited but develops quickly as cones mature (2-3 mo = adult categories)
As infants get older, what do they prefer?
More complex patterns
What does the preference of complex patterns in infants mean?
Means better understanding of structure
What do edges and contrasts provide?
Information on the boundary of an object
Depth and how to grasp objects
Greater neural activation
Helps develop neural pathways of pattern recognition
Why are infants drawn to faces?
They are 3D, moving, have areas of high/low contrasts, and regulate visual stimulation
May be genetically preprogrammed to prefer faces
How does social learning affect preferences for faces?
Infants prefer novel faces of same sex as their own caregiver
also have a preference for faces matching their own race
prefer smiling faces by 3 mo
What is object constancy?
Perception/belief that an object remains constant, despite changes in the way it looks
Conditioning studies suggest that infants have innate knowledge of?
Shape constancy and size constancy
Why are constancies important?
Help maintain a stable perceptual world
What is the evidence that object constancy develops relatively early in children?
The conditioned head turn paradigm
When does depth perception start?
2-3 months old (learn to focus on objects at different distances) and by age 4 years = adult level
Explain the idea behind the visual cliff experiment?
infants should we unwilling to cross if they can truly perceive depth
Similarities in infant and adult heart rate?
Adults heart rate decelerates in response to novel/attractive and interesting stimuli
Accelerates in response to dangerous/aversive stimuli
What 3 ways can we perceive visual depth?
Kinetic cues (1-3 mo)
Binocular depth cues (4-6 mo)
Pictorial distance cues (5-7 mo)
Explain Kinetic cues
Produced as a person/object moves
- motion parallax: close = faster, further = slower
- interposition: closer objects obscure furter objects
What are binocular depth cues?
inter-eye disparity is greater for closer than further objects
What are pictorial distance cues?
linear perspective and texture gradient - tested with reaching studies
What can we use to test hearing in infants?
Habituation (HR chaning, sucking, breathing)
At what age can foetus respond to sounds?
24 weeks in utero
How do we know infants can hear at birth?
Respond with startle reflex, fists, crying
By 3 days old, infants can?
orient to the direction of sound (prefer complex to pure)
distinguish:
2 vs 3 syllables
happy vs negative speech
tones
Which parts of auditory sensation continues to develop until age 10?
Sensitivity and pitch discrimination
Differences between adults and infants in sound sensitivity?
Newborns not as sensitive to sound as adults - newborns more sensitive to low pitch
What age can infants locate sound?
2 months
Smell and taste development in infants?
Well developed in last months in utero - highly developed at birth
Food taste preferences changes?
Changes with age
- sweeter tastes preferred by foetus
- salty tastes preferred by 4 mo
How early do foetus respond to touch?
8 weeks
Why is sensitivity to touch important for?
For exploring the environment and for positive emotional development
What is haptic perception?
Use of touch to explore objects
- oral manipulation is most informative
- 3 yo = adult like exploration
How do infants respond to pain?
with distress (crying, blood elevation) but also influenced by others reactions and the environment
How can we assess older children’s experience of pain?
Faces pain scale (pointing to one that best represents)
Explain the concept of intermodal perception
The ability to combine input from different senses to form a perception of unitary events or objects
Infants preferred sucked on dummy despite new visual stimulus of other dummy - suggesting IP is an innate skill that improves with experience
