Cognitive Development: from infancy to childhood Dr Hester Duffy
Measuring infant abilities • No language • Very little motor control • Eye movements • Sucking • Involuntary functions
Preferential Looking:Fantz (1961) Two stimuli presented visually Time spent fixating on each is measured
Brennan, Ames & Moore, 1966 2 months 4 months 6 months
Early Visual Preferences • Preferred level of stimulus complexity that increases with age • Symmetry • Interesting shapes
Habituation:Slater, Morison & Rose (1983) Simplest form of learning
Habituation • Allows visual preferences to be induced • Wider variety of stimuli can be tested • Shows basic memory and learning processes
Violation of Expectations • Single visual stimulus in each trial • Looking time measured • Between subjects/trials
Learning and Memory • Prenatally: • DeCasper & Spence (1986) • Infants prefer to listen to a story their mother has read while they were in the womb • As newborns – habituation • For actions • Rovee-Collier et al (1997) • Infants can learn to move their leg to make an mobile move
Proto-language • Starts in the womb • Preference for familiar language, mother’s voice, familiar sounds at birth • Vocalisation • Different cries • For fun
Early Visual and Auditory Perception • Innate “tuning” – human voice, focal distance • Useful preferences; female voices, faces? • Fast development of adult-like perceptual processes
Stage Theories • Children show qualitatively different reasoning at different stages in development • The characteristics of that reasoning are shown across several different areas • They are “domain-general” • Stages do not have to occur at the same age, but they should occur universally and in the same order
Piaget • Children begin with many wrong assumptions • Egocentrism • No object permanence • Sensori-motor knowledge • Infants only know an object by perceiving it and acting on it
Piaget • Object permanence paradigm
Object Permanence • Child plays with object / toy • Toy hidden from view • No search shown • Motor abilities not a limitation
Baillargeon & Graber (1987) • More recent measures of object permanence • Violation of expectations technique • 5 ½ month old infants
Hood & Willats (1986) • 5 month old infants shown an object to one side • Lights extinguished (object no longer visible) • Significant reaching to the area where the object was.
Infant’s knowledge of the world • Piaget: • Infants begin with v. little knowledge • Understanding of the nature of objects develops through infancy • Baillargeon • Piaget’s tasks are too demanding • Synchronise watching, remembering, reaching
Piaget – into childhood • “child as a scientist” • Development is about progressive adaptation to the environment (make sense of the world) • Assimilation • Relating new information to pre-existing structures • Accommodation • Developing the old structures into new ones because of contradictions or incompatibilities • These are moderated by equilibration - force for stability
Weaknesses • Most of us have several inconsistencies and incompatibilities in our beliefs • We only use 10% of our brain • Rivers flow from north to south • Conspiracy theories • Ten year olds don’t notice a problem here:
Weaknesses • Over-estimates the consistency of child’s responses • Sometimes children vary apparently randomly in the level of reasoning used • Level of reasoning can be highly dependent on task and context • What about social influences? • Piaget does not give much time to role of education • Says peers would be more effective tutors than adults • In general, he underestimates preschoolers and overestimates adolescents
The pre-operational stage • 2 ½ - 6 years of age • Reorganisation of thinking into mental operations • Can consider amounts and perceptual size • But: • Egocentric • Finds it difficult to consider other views • Lack of logical reasoning • Reversibility – actions can be reversed • Centration • Focus on one aspect or perception
Pre-operational stage • Development of ‘symbolic representation’ • Pretend play • Drawing of people and things • Using language
The concrete operations stage • 6-12 years • Beginnings of verbal reasoning • Able to consider two different views simultaneously • Limited to present situations and two variable tasks
Concrete Operations • Able to recognise logical necessity • Which actions are reversible or not • When quantity is conserved • Able to consider alternative views • Others have different knowledge and beliefs • Objects can be classified in different ways
The formal operations stage • 12 – 16 years • Not universal • Beginnings of scientific thought • Hypothetical reasoning (counter-factual) • Able to think abstractly about multiple causes • Able to formulate rules that go beyond specific instances • Justice • Morality
Piaget’s Tasks • Solved in the concrete operational stage: • Operations involving logical necessities and reversibility • Conservation • Classification • Tasks involving taking different perspectives • Solved in the formal operational stage: • Tasks involving scientific reasoning • Balance beam • Pendulum
Classification Tasks • Show the child the set of wooden beads, some of which are white and some are brown. • Are there more brown beads or white beads? • Are there more white beads or wooden beads?
Language Difficulties • What does ‘same’ mean in this context? • Why is the same question asked twice? • It is unusual to ask a question comparing two levels of categorisation • Children look for what the experimenter ‘wants’ them to say, not for truth
Task Situation • Actions are not embedded into a logical format • Why are objects moved etc? • Tasks need to be embedded in a context that makes “human sense” to a child • Donaldson (1978)
McGarrigle & Donaldson (1974) Naughty Teddy ‘messed up’ the counters. Are there still the same number? Traditional task: 33.7% correct Naughty teddy task: 71.9% correct Are children really understanding the task?
Moore and Frye (1986) Naughty Teddy added some counters. Many children said there were still the same number in both rows. Just discounting Teddy’s actions Similar results if the experimenter didn’t see the transformation
Seigler (1995) • 3 groups of 5-year-olds given conservation tasks • Given feedback on responses • Asked to explain reasoning and given feedback • Given feedback and asked to explain the experimenter’s reasoning Group 3 showed most success • They get more of an insight into why the experimenter is asking questions • Zone of Proximal Development?
Conservation Revisited • Even with clearer task demands, task is difficult before 5 years • McGarrigle and Donaldson may have over-estimated conservation abilities • Discounting perceptual information remains difficult for pre-schoolers
Egocentrism D B C A Child sits here What can someone who is sitting at B, C, or D see? Describe it or select the correct picture from a set
Egocentrism – making Human Sense • Hughes – where could the robber hide from the policeman? • Three year olds were 90% correct • An understanding of eye gaze • But does that mean understanding different knowledge states?
Summary • Infant brains are relatively large, but show significant development • Children are able to perceive within the womb • Modern experimental techniques allow us to measure infant abilities • Visual and auditory perception quickly becomes adult-like • Infants seem to quickly develop an understanding of the world
Summary • Piaget describes development in a series of stages • Later research has cast doubt on his tasks, though some elements remain important • There continues to be debate about whether this implies that the stage theory should be discarded