Sleep/Wake Cycles
Regular Sleep
Irregular Sleep
Drowsiness
Alert inactivity
Waking Activity
Crying
Week 2-6 14-16 hours of sleep
Week 13-28 sleep through night and require 2 naps
Autostimulation Theory - if given a lot of stimulation when awake, babies will spend less time in REM sleep Therefore REM sleep may simply be an attempt to provide stimulation.
SIDS - sudden infant death syndrome
more prevelant history of
respitory problems
abnormal heart rates
moms who smoke or use narcotics
in winter months
between ages 2 and 4 months
Crying - 3 different patterns - Basic, Angry, Pain
Sensation and Perception
4 methods for testing infants
1) Preference method
- present 2 stimuli to a baby at the same time and see which one the
infant attends to
(For example, present 2 pictures - which one does the baby look at?)
- the one that he baby attends to longer is the preferred stimulus
- Using this method research has found
- preference for faces, patterned stimuli, concentric circles
- If not preference is shown for either stimulus,
- then possibly no discrimination between the stimuli
(differences are too subtle to notice)
- then possibly both stimuli equally stimulating
2) Habituation method
- repeatedly present 1 stimulus to infant until familiar
- then present 2nd stimulus
- if dishabituation, then infant recognizes the difference between
the 2 stimuli
- if no dishabituation, then no discrimination
- looking time, heart rate, respiration used as measures
3) Evoked Potentials and/or Event Related Potentials
- measured by EEG (brainwave) recordings
- changes in the ongoing activity of the brain to the presentation
of a stimulus reflect detection and processing of the stimulus
- no changes in the ongoing activity of the brain to the presentation
of a stimulus reflects no detection of the stimulus
4) High Amplitude Sucking
- using a special pacifier 1st identify the base rate for
sucking
- when baby sucks faster/harder, present stimulus 1
- when sucking returns to baseline, stimulus 1 goes off
- present stimulus 2
- if sucking increase (cont stim2), then discriminate difference
- if sucking remains low, then no difference
Vision - Sensation
At birth, babies can
- detect changes in brightness (pupillary reflex)
- detect movement so long as it is slow
- will track face-like stimuli more than other patterns
- can see colors (prefer color over gray) but have difficulty detecting
colors close in wavelength (blue/green, red/orange)
By 3 month
can discriminate basic colors
- purple, blue, green, yellow, orange, red, black, white
can recognize changes in brightness does not change color
Visual acuity
- 20/600 at birth
- 20/100 by 6 months
- 20/20 by 1 year
Visual Perception
Perception of faces -
1 months
- Infants look at outer boundaries more than the internal features
of the face
2 months
- Infants focus ont he mouth and eyes
3 months
- recognize mom's face and preference for mom's face
- babies also look longer at attractive faces
3-7 months
- quicker to discriminate familiar faces
- mom's faces study
8-10 months
- interpret emotional expression
Depth
Monocular - 2 dimension
Stereoscopic - conversion of 2 flat pictures to
create a picture with depth
Binocular - 3 dimension
Monocular Depth Cues (Pictorial)
- linear perspective
- texture
- size cues
- interposition
- shading
Visual Cliff
- glass top surface where one side "shallow" has a pattern that appears
directly beneath the glass and the other side "deep" has a pattern that
appears some distance below the glass.
- 1 1/2 months
- deep side heart rate decreases suggesting interest but not fear
- shallow side - no heart rate change
- 6.5 months
- 90% infants crawl toward mom on the shallow side
- 10% infants crawl to mom on the deep side
Size Constancy
Slater - 2 day old infants
- 2 cubes - 1 large (10.2 cm)
- 1 small (5.2 cm)
- habituate to 1 cube in 6 different locations
- creates different retinal images
- test for dishabituation with cubes at different distances but with
retinal image being identical
- prefer (look longer) at the novel cube
Hearing Sensation
- Sound need to be louder for newborns to hear them
- newborns can detect changes in loudness duration direction, and frequency
- Reaction to voices
- attentive to voices
Especially hi pitched female voices "Motherese"
- DeCasper and Spence
- prenatally read "the Cat in the Hat"
2x per day for last 6 weeks of pregnancy
- 2 days of age
- babies read 1 of 3 stories
"The Cat in the Hat"
"The Dog in the Fog"
"The King, the Mouse, and the Cheese".
- used high amplitude sucking to examined newborns ability to identify
the difference between the stories
- Findings
- increased sucking to mom's voice vs stangers
- slight increase to "The Dog in the Fog"
- Dramatic increase to "The Cat in the Hat"
Phonemes - basic speech sounds
- 1 week
- can discriminate vowel sounds
- 2-3 months
- can distinguish similar between sounding phonemes
in every language (lasts til approx 6 months)
- by 8 months can only discriminate phonemes in native language
Taste and Smell
- preference for sweets
- 1-2 weeks old can recognize mom by smell
Touch - Temperature and Pain
- premature infants better progress when stroked/massaged in isolettes
- touch is primary means of acquiring new information
- circumcision
- topical anesthetic during surgery and sugary solution
following can help to calm infant and lessen stress
Intermodal Perception
Perceptual Learning - actively explore objects in our environment and
detect distinctive features
Learning
Habituation
Classical Conditioning
- UCS - something in baby's mouth
UCR - sucking
CS - nipple/bottle
CR - sucking
- higher order conditioning
UCS - bottle
UCR - sucking
CS - ? Hungery?
CR - sucking
Operant Conditioning
- positive and negative
reinforcement
- positive and negative
punishment
(responses to vocalizations
and facial expressions)
Imitation
of facial expressions
- between 7 and 72 hours
babies will imitate
mouth opening, sticking out your tongue, open/close their mouth, protruding
lower lip (pout), smile/happiness
(Remember babies eye sight is about 20/600 at birth so gestures need
to be exaggerated for baby to see them)
- by 9 months imitate behavior
- between 14 and 18 months
defered imitation
-response can be observed long after initial imitation (24 hrs, 1 wk)
- as a child get older,
- behaviors will cross context/environments
- behaviors become more complex
- incorporate verbal descriptions into imitative behaviors
- used to acquire basic personal and social competencies
- gain a richer understanding of routines and regulations
Rovee-Collier - 2-3 month olds
- tied a ribbon around the ankle of the baby
- kicking made the mobile move
- 2 month olds could remember for up to 3 day
- 3 month olds could remember for up to 1 week
- if given a reminder ... move the mobile ... the infant remembered
(started kicking a lot) for up to 2-4 weeks following initial training
- early learning is context dependent - if the same mobile or the same
environment is not used, then they show little or nor retention