Perceptual and Sensor motor development Flashcards
Outline Perceptual development at birth
Least developed sense at birth – VISUAL PROCESSING AS WELL AS STRUCTURE OF THE EYE
• Visual Acuity: Sharpness of vision; clarity that fine details can be detected (e.g., Maurer & Maurer, 1988)
• Newborn
• Can distinguish visual forms if close enough
• 20/400 vision (really bad vision)
Outline visual acuity at 6months and 8months
outline colour perception at newborn adn 2-4 months
Visual Acuity
• 6 mo: Acuity approximates normal adult vision
• 8 mo: More interest in distant objects, tiny objects
Colour Perception
• Newborn: Prefer colour to grey
• 2-4 mo: See full colour spectrum
Outline the preferential looking method and pattern perception
Looking chamber Fantz (1961). © David Linton- INfaAT LIES DOWN- PRESENT 2 DIFFERENT STIMULI- IF iNFANT SPENDS MORE TIME LOOKING AT one thing moreso than the other we know the infnat knows they’re different.
Paired stimuli Fantz & Nevis (1967) © Wayne State University Press
Pattern Perception
• Newborn: Prefer patterns to plain stimuli
• 2 mo: Prefer more complex patterns to simpler ones
• Toy design…any benefit past 6 mo?
ourline visual scanning
Visual scanning • Eye tracking method • Prefer high-contrast areas • 1 mo: Edges • 2 mo: Internal features • Sticky fixation: Difficulty disengaging visual attention away from one feature to focus on another • 6 mo: Adult-like scanning Maurer & Salapatek (1976
Outline the improvement in how infants see shapes
Perceiving parts vs. wholes (e.g., Cohen & Younger, 1983)
• Not just edges & corners, but whole shape
• Improves over 1st yr •
4 mo: See subjective contours
Perceiving parts vs. wholes
• 12 mo: Recognise incomplete line drawings (Rose et al., 1997)
Define Habituation in terms of infant visual development
A form of learning reflected in a decrease in the strength of response to a repeated stimulus
Outline infant facial perception
Nature: Newborns track faces more than other stimuli (Johnson et al., 1991)
• Nurture: This bias gives them much experience with faces
- 2-4 mo: Prefer more complex facial stimuli; prefer mother’s face; discriminate individual faces
- 5-12 mo: Discriminate emotional expressions
Outline Depth Perception in infants
3 points
- Kinetic cues (1 mo)- cues coming from motion
• Motion parallax: Nearby objects appear to move faster than distant ones - Binocular cues (3-5 mo)
• Disparity: Brain perceives depth when combining slightly different angle from each eye - Pictorial cues (5-7 mo)
• Interposition: An object that overlaps another appears nearer (Granrud & Yonas, 1984)
• Linear perspective: Parallel lines appear to converge in distance (Arterberry et al., 1991)
• Relation between depth perception development and motor development?
Outline the Visual Cliff and what it means
• Visual Cliff (Gibson & Walk, 1960)
• Nature-nurture research- different species- which ones would cross which ones don’t- when born
• Compare depth perception in infants of different species
• Humans: More crawling experience= more avoidance of cliff
e.g. Baby walkers- now banned
Everytime babies learn new form of locamotion relearn depth perception e.g. will stop at a edge when crawling but when walking will walk right off.
Outline Auditory developmenet threshhold
• More mature at birth than vision
• Auditory threshold: Quietest sound can hear (e.g., Aslin et al., 1998)
• Newborns less sensitive than adults to quietest sounds
• Most sensitive to sounds in range of speech
Outline Infant Auditory Localisation
• Localisation (e.g., Clifton, 1992)
• Newborn: Turn head towards sound
• 7 mo: Know when sounding object in dark is within reach (will reach for it if it’s 15cm away and won’t if it’s 60cm away)
• 2 yr: Adult-like Perceptual Development: Hearing
Use preferential observational behaviours to detect whether infants enjoy or dislike stimuli…
Outline Music in infant
Music (e.g., Trainor & Heinmiller, 1998)
• Newborn: Prefer music to nonmelodic sounds
• 4-6 mo: Prefer more common chords
• 6 mo: Distinguish Western vs. non-Western music scales
Outline Speech perception in Infants
Speech (e.g., DeCasper & Spence, 1986)
• Newborns suck preferentially to hear:
• Infant-directed speech (motherese)
• Voice of mother vs. stranger
• Familiar rhyme heard during last 6 weeks of pregnancy vs. novel rhyme
Younger infant prefer familiar- if delay between stimuli will also prefer familiar- emotional stimuli also skews
Old Vs. New
Outline Taste perception in infants
- Newborn: Detect 4 main tastes from 2 hrs old (& prefer sweet)
- Survival value
• 4 mo: Prefer salty to plain
Done by detecting facial expression.
Outline Smell in infants
(e.g. Rosenstein & Oster, 1988)
• Innate?: Universal facial expressions for pleasant (sweet) vs. unpleasant (rotten/fishy) odours
• Newborns prefer familiar odours
• Amniotic fluid
• Breast milk
• Perfume
Make sense- as if threatened in wild- recognition from smell
Diet during pregnancy effects bbaies familiarity of smell e..g garlic or annis
Outline touch as an infant sense
• Pain
• Same pain receptors as adults
• Circumcision (Gunnar et al., 1985) cried, stress hormones in blood, increase in heartrate- indicative of pain
• Object discrimination (Streri et al., 2000) habituate to objects as well iin ters of tactile behaviour- drop it if over stimulated.
Can now use local anaesthesia- general anaesthesia is risky
Pressure, texture, temperature, moisture
• Face, hands & feet most sensitive
Helps physical growth e.g. stimulation on preterm babies to help them gain weight
outline 4 essenstial newborn reflexes
Rooting Sucking Swallowing Swimming Reflex: Involuntary response to external stimulation (e.g., McGraw, 1940)
outline 4 non-essentail newborn reflexes
Nonessential (don't stay and not obvious what evolutionary advantage they give) Moro (startle) Gripping (palmar grasp) Stepping Babinski
What is Cot death or SIDS?
Cot Death or SIDS (Sudden Infant Death Syndrome)
2016 1 in ever 3,200 die
Unexplained sudden death of infant less than 1 year, usually during sleep
• Critical Period: Risk at 1-4 months when reflexes wane • Respiratory occlusion reflex
• Vulnerable Infant: Often physical problems from birth (e.g., LBW)
• External ‘Stressor’ (e.g., exposure to smoking, sleep position)
Outline the back to sleep campaign
SIDS: Back to Sleep Campaign in US
79% reduction in cot death since 1991
Now advised to put nothing in cot- don’t share bed with baby
Put to sleep on back
give two motor development patterns
- Cephalocaudal (head to tail): Motor control proceeds from head to toe
- Proximodistal (near to far): Motor control proceeds from trunk to limbs
outline the sequence of an infants fine motor hand skill
Proximodistal: Arms, hands, fingers
• Newborn: Pre-reaching (e.g., von Hofsten, 2004)
• 3-4 mo: Goal-directed reaching
• 5 mo: Grasp anticipates object orientation (e.g., Lockman, 1981)
• 9 mo • Anticipate object size
• 18 mo: Tool use (e.g., use spoon to feed self; McCarty et al., 2001)
