infancy
period between birth and 2 years.
changes in infancy
- A period of rapid growth and development in a range of areas: • Physical § Growth and motor development • Perceptual • Cognitive § Memory and attention • Language • Social and Emotional
newborn reflexes
• Reflexes are unlearned, involuntary responses to stimuli
• Some are highly adaptive and necessary to survival.
• Survival reflexes are adaptive
• E.g. breathing, eye-blink, sucking
• Primitive reflexes are less adaptive and typically disappear in early infancy
• E.g. Babinski reflex (stroking the bottom of the foot), grasping reflex
These reflexes can show abnormal development if they are still present after infancy or are weak or absent during infancy.
infancy motor development
• Motor development follows two trends
• Cephalocaudal (head to tail)
Proximodistal (gain control of the centre of the body before the limbs) e.g. can sit before it can walk.
gross motor skills
Movement of large muscles of arms, legs, and torso
fine motor skills
Movement of small muscles such as fingers, toes
milestones
- Crawling is not counted as a developmental milestone and is highly variable as some children do not crawl.
- Usually infants can move themselves around to some degree by 7 months.
- It is important to take milestones with a grain of salt as children do so at a different age.
- High levels of cultural differences in development.
- Unsure if it is a nurture issue or biological predisposition.
- High levels of cultural differences in development.
infant perception
- How do we know what babies can see/perceive/know?
- Habituation
- Preferential looking
- Evoked potentials
- Operant conditioning
habituation
• Habituation
• The process of learning to be bored with a stimulus
○ After repeated presentation with the same visual stimulus, the infant becomes bored and looks away
○ If a different stimulus is presented and the infant regains interest, researchers conclude that the infant has discriminated between the two stimuli
• Habituation can be used to test for discrimination of stimuli by all the senses
• To know something is interesting we have to know it is different.
• Habituation paradigms are useful for assessing perception in infants.
assessing abilities
- Evoked potentials
- Researchers can assess how an infant’s brain responds to stimulation by measuring its electrical conductivity
- Operant conditioning
- Infants can learn to respond to a stimulus (to suck faster or slower or to turn the head) if they are reinforced for the response
vision
- At birth, infants have vision, but lack acuity
- Can see more clearly about 20 - 25cm
- Objects at 6 metres as distinct as objects at 180 metres for adults
- Improves steadily during infancy
visual preferences
• Attracted to patterns that have light-dark transitions, or contour
• Attracted to displays that are dynamic rather than static
○ Infants are drawn to highly contrasting images, but not if they are highly complex.
• Young infants prefer to look at whatever they can see well
• Around 2 or 3 months, a breakthrough begins to occur in the perception of forms
• Initially, infants from birth to 1 month old look at the outside of an object but begin to look at the interior at around 2-3 months old.
depth perception
• Gibson and Walk (1960): Classic study to examine depth perception in infants using the visual cliff
○ Tried to explore what infants knew about depth perception.
○ Created a ‘fake’ cliff whereby they placed the babies in the middle of the floor. Asked the mother to go to either the shallow or deep end of the cliff.
○ Babies went to their mothers nearly all the time on the shallow side but at around 6 months are much more reluctant if she is on the deep side.
○ Infants of around 3 months can recognise the difference between each side but do not show the same fear as older infants.
• Infants can perceive the cliff by 2 months (tend to be curious rather than fearful)
hearing
- Basic capacities are present at birth
- Can hear better than they can see
- Can localise sounds
- Can be startled by loud noises
- Can turn toward soft sounds
- Prefer relatively complex auditory stimuli
- Can discriminate among sounds that differ in loudness, duration, direction, and frequency/pitch
- Hearing is advanced quite early on and can discriminate between ‘pa’ and ‘ba’ for example.
infant perception: early development
• Sensory experience is vital in determining the organisation of the developing brain
• The visual system requires stimulation early in life to develop normally
○ Early visual deficits (i.e., congenital cataracts) can affect later visual perception
• Exposure to auditory stimulation early in life affects the architecture of the developing brain and influences auditory perception skills
infant cognition: Piaget’s sensorimotor stage
- Sensorimotor stage
- The world is understood through the senses and actions
- The dominant cognitive structures are the behavioral schemes that develop through coordination of sensory information and motor responses
- 6 substages (no need to learn the stages but be familiar with them).
- Piaget: from French Switzerland.
- The way that we develop is by changing the way we think over time.
- Accomodation is where we use existing knowledge and expanding it to make new knowledge.
substages of sensorimotor
- Reflexes: (first month)
- Reflexive reaction to internal and external stimulation
- Primary circular reactions: (1-4 months)
- Infants repeat actions relating to their own bodies
- Secondary circular reactions: (4-8 months)
- Repetitive actions involving something in the infant’s external environment
- Coordination of secondary schemes: (8-12 months)
- Secondary actions are coordinated in order to achieve simple goals (i.e., pushing or grasping)
- Tertiary circular reactions: (12-18 months)
- Experimentation; actions are repeated with variations
- Beginning of thought : (18 months)
- Symbolic thought permits mental representation, imitation, and recall
object permanence
• Object permanence develops during the sensorimotor period
• From 4-8 months, “out of sight, out of mind”
• By 8-12 months, make the A-not-B error
• E.g. Playing with a toy, then hide it behind a box, the baby will go and find it. Do this multiple times. Later, fide it behind something else, when making A not B error the baby will continue to look behind the box.
○ They know that it continues to exist but continue to look in the place that they have found it before.
• By 1 year, A-not-B error is overcome, but continued trouble with invisible displacement
By 18 months, object permanence is mastered
problems with Piaget’s theory
- Some of the evidence relies too much on the infant’s motor skills and memory.
• Rather than just object permanence, the child may know that it continues to exist but may not be able to go to the place or remember where is was. - Can also be reinforcement
• If the mother makes a fuss about location A the baby may look there again because of the conditioning.
development of object permanence
Research suggests that infants may develop at least some understanding of object permanence far earlier than Piaget believed
• By 3 months, infants appear to understand that objects have qualities that should permit them to be visible when nothing obstructs them
SEE DIAGRAM
psychosocial development: emotions
- Emerge throughout infancy
- Earliest emotion – crying
• Hunger, anger, pain, fussiness - Other emotions
• Joy and laughter, 3 - 4 months
• Wariness, 3 - 4 months
• Surprise, 4 months
• Fear, 5 - 8 months
• More complex emotions in toddlerhood
○ Pride, guilt, shame.
○ These relate to more implicit understanding of a behavioural standard.
○ Need a sense of self to express these emotions.
○ Exert a sense of self because they can case things to happen.
sense of self
- Infants develop an implicit sense of self through their perceptions of their bodies and actions
- In the first 2 or 3 months, infants discover they can cause things to happen
- After 6 months, infants realise they and other people are separate beings with different perspectives, ones that can be shared
- Around 18 months, infants recognise themselves visually as distinct individuals
joint attention
Joint attention is when the child realises that the caregiver has a different perception of the world than they do.
rouge test
• Lewis and Brooks-Gunn (1979): Rouge test
○ Therouge testis a self-recognitiontestthat identifies a human child’s ability to recognize a reflection in a mirror as his or her own. Usingrougemakeup, an experimenter surreptitiously places a dot on the nose and/or face of the child
