Cognitive Development

Cognitive Development Cognitive Development  What is it?  Cognitive psychology as a field studies adult cognition (high school and up) whereas the sub-field cognitive development looks at changes in cognition across the whole life span (from infancy to gerontology) Qualitative and Quantitative changes in thinking  Qualitative = general regularities and differences in the essential attributes of thinking   Quantitative = increasing knowledge and ability  Who studies it?  Cognitive-Developmental Psychologists:  psychologists who investigate how mental skills build and change across the life span  Subfield focusing on brain physiology = Developmental Neuroscientists Cognitive Development  Nature vs. Nurture debate  Nurture = environment  Strict nurture side argues the infant is devoid of natural tendencies upon which the experiences of the world are recorded– all development based on environmental influences  tabula rasa = blank tablet  Nature = Genetics (biology)  Strict nature side argues infants possess certain set neurological and physiological potentials based on DNA blueprint  Brown hair, shyness, intelligence, personality, etc. – all biologically programmed Cognitive Development  Nature vs. Nurture debate– 3 Perspectives  Associationist Perspective     English Philosophers of 17-1800s (Locke, Hume, Mill) Suggest infants come into the world with only minimum capabilities, primarily to associate experiences with each other Thus, infants acquire virtually all capabilities/concepts through learning Behaviorism (Skinner) = strict nurture argument such that all development was a result of operant learning  Operant learning: goal direct actions for specific consequence—obtain reward/avoid punishment  Modeling: behavior based on observation and copying of actions of others Jean Piaget 1920-70s In addition to associationistic capabilities, infants have several important perceptual and motor capabilities Few in number and limited in scope, these capabilities allow infants to explore their environment and construct increasingly sophisticated concepts/understandings  Example: contends infants up to 6 months do not have mental representations but by actively manipulating/investigating objects, become capable of forming representations later in the first year of life  Constructivist Perspective    Cognitive Development  Nature vs. Nurture debate– 3 Perspectives, cont.  Competent-Infant Perspective  Carey, Gelman, Spelke 1990’s-present   Modern research suggests previous 2 perspectives seriously underestimated infant capabilities- shows infants have much wider range of perceptual and conceptual skills Research shows:  Infants with in 6 hours recognize mother’s face, B.O., breast milk taste  Infants 24hrs after birth can perceive depth of objects (closer or farther)  By 3 months, infants show some understanding of simple object movement– including occlusion (out of sight), gravity, that solid objects cannot move through each other (labeled intuitive physics)  Infants also possess primitive general learning mechanisms that foster obtaining wide range of new knowledge * Imitation– 2 day olds will mimic adult head movement, 2 week olds mimic sticking out tongue Cognitive Development  Factors that effect cognitive development  Neurological and physical maturation (growth) and deterioration of a person  Family, social/cultural and educational surroundings of a person  Interaction between a physically changing person and his/her environment  Most modern psychologists agree that cognitive development occurs as a result of the interaction between maturation (nature) and experience (nurture) Major approaches to Cognitive Development  The Big 5:      Piagetian (Ages and Stages Theory) Neo-Piagetian Vygotskyan (Sociocultural Theory) Information Processing Neuroscientific General Principle of Cognitive Development  Regardless of theoretical approach:       Over the course of development, people seem to gain more sophisticated control over their thinking and learning With age, people become capable of more complex interactions between thought and behavior People engage in more thorough information processing with age– older = encode more information from problems People become increasingly able to comprehend successively more complex relations over the course of development Over time, people develop increasing flexibility in their use of strategies or other information Accumulation of knowledge continues across the life span- may gain greater wisdom– insight into themselves and the world around them Sternberg General Principle of Cognitive Development  Each approach picks a theoretical foundation:  Domain General:  All domains (levels of knowledge) develop as a result of universal cognitive growth (level of thinking the same regardless of type of knowledge) Different domains develop at deferent rates (can have higher level of thinking for one area of knowledge than another area)  Domain Specific:  Three main domains: biology, physical, psychological Piagetian Approach Ages and Stages Theory     Jean Piaget (1896-1880) Swiss Zoologist/biologist/psychologist Began studying his 3 children (naturalist), then did clinical experiments Arguably most influential developmentalist with research spanning from 1920s to 1970s (dominant in 1960s-70s with cognitive revolution)  Most comprehensive theory of cognitive development  Revolutionized study of children’s thinking by suggesting the incorrect answers as important in examining children’s cognition as correct answers Piagetian Approach Ages and Stages Theory  Main assumptions of Piagetian Theory:     Function of intelligence is to aid adaptation to environment  with cognitive development = increasingly complex responses to the environment Children as active learners (BUT) Cognitive development proceeds from inside out – emphasizes biological (development before learning) Coherent logical systems underlie children’s thought – Domain General  Different from adult systems  Different at different ages Piagetian Approach Ages and Stages Theory  Main assumptions of Piagetian Theory:  Development occurs in stages that evolve via Equilibration  Equilibration: children seek balance (equilibrium) between environmental encounters and current cognitive capabilities (structures and processes) they bring to the encounter  Equilibration involves processes which result in more sophisticated levels of thought:  Equilibrium: Child’s existing schemas (mental frameworks) are adequate for confronting/adapting to challenges of environment  Johnny calls all 4-legged small furry animals ―doggie‖ like his own dog   Disequilibrium: imbalance occurs when child’s current schemas are inadequate for new environmental challenges Assimilation: incorporation of new information into a child’s existing schema  Johnny has a Poodle, at park sees Huskie, Great Dane & Chow  Accommodation: changing existing schemas to fit relevant new information about the environment  Johnny goes to zoo, sees different animals that mom labels with different names, so Johnny creates overarching schemas for animals, into which he fits his schema for dogs. Piagetian Approach Ages and Stages Theory Changing Schemas of the Earth  5th grade From preschool through about the 5th grade, children gradually assimilate and then accommodate their schemas to form an accurate representation of the earth’s shape. Preschool Piagetian Approach Ages and Stages Theory  Main assumptions of Piagetian Theory:    Piaget contended the Equilibrative processes of Assimilation and Accommodation account for all changes associated with cognitive development Piaget contended disequilibrium was more likely to occur during periods of stage transition Cognitive development involved separate, discontinuous stages:  Sensorimotor Stage  Preoperational Stage  Concrete-Operational Stage  Formal Operational Stage Piagetian Approach Ages and Stages Theory Piagetian Approach Ages and Stages Theory   Sensorimotor Stage 0--2 years old (infancy): Involves increases in number and complexity of sensory (input) and motor (output) abilities  Starts with reflexes (rooting, grasping), then moves to conscious, intentional control of actions (operant learning)  Understanding of objects is based on what can be physically done with them Early infant cognition focused on immediate perception with no enduring mental representation for objects.   Do not have sense of Object Permanence– knowledge that objects continue to exist even if not immediately perceptible    Until approx. 8-9 months- if an object is removed from sight the child forgets about it. After 8 months- object permanence occurs Latest research calls this into question but infants appear to not have same concept of the permanence of objects that adults do  By end of sensorimotor period (18-24 months), Piaget contends children show signs of Representational Thought-- internal representations of external stimuli Piagetian Approach Ages and Stages Theory      Preoperational Stage 2--6/7 years old (early childhood): Children actively develop internal mental representations (propositions and images) Children engage in pretend play Children are egocentric, especially in their language (cognitively, not personality trait) – can only view the world from one perspective = their own! Children use symbols (words/images) but cannot reason logically   Centration: a tendency to focus on only one especially noticeable aspect of a complicated object or situation  Often fooled by visual appearance rather than reality of situation Only one dimensional thinking- ignore other, relevant aspects of object/situation  At this stage the child lacks Conservation: the ability to understand that if one rearranges an object, it is still the same basic object (the object is conserved under transformation). Piagetian Approach Ages and Stages Theory  Examples of conservation of quantity: child is mentally able to keep in mind a given quantity despite observing changes in the appearance of an object or subject– can now think in 2 dimensions (can decenter). The ability to conserve marks the transition from the Preoperational stage to the Concrete-Operational stage of cognitive development.  Piagetian Approach Ages and Stages Theory  Concrete-Operational Stage 7—11/12 years old (middle childhood):  Children able to mentally manipulate internal representations  Begins to logically reason on concrete objects/situations  Can perform operations on thoughts and memories BUT only related to concrete objects (thoughts and memories on cars, food, toys and other tangible, touchable things)     Displays conservation– begin to formulate internal rules about how the world works and use rules to guide reasoning (rather than appearance alone) Displays Reversibility– can judge quantities because understands potentiality of reversing an actual physical (concrete) action and grasps the logical implications Displays Classification– grouping objects into hierarchies of classes and sub-classes Displays Seriation (ability to string together a series of elements based on some underlying relationship) and Transitivity (A> B> C, so A>B and B> C, therefore infer that A > C) Piagetian Approach Ages and Stages Theory  Formal Operational Stage 11/12—onward:     Display mental manipulation on abstractions and symbols that may not have physical, concrete forms Can understand things not directly experienced Can take perspective of others Purposefully seek to create a systematic mental representation of environmental situations Piagetian Approach Ages and Stages Theory  Summary/Criticism of Piagetian Age and Stage Theory:  Stages are separate and defined by the way knowledge is represented with transitions between stages characterized by becoming able to do criterion tasks  Other research suggests that cognitive development is a gradual, continuous process (not jump up to next step)   Stages occur in fixed order and build upon each other  The basic sequences is still considered valid and research offers much support Stages occur roughly at same time for different children  Research suggest rate of development might be sooner– earlier ages than Piaget thought possible  Research suggests Piaget underestimated the cognitive ability of young children (especially infants)   Measures did not illicit full abilities of children, underestimated importance of language during tasks Measure of low motor ability may not be indicative of similar cognitive capability Piagetian Approach Ages and Stages Theory  Summary/Criticism of Piagetian Age and Stage Theory:  Stages are irreversible: once child enters new stage, thinking reflects that stage regardless of domain, specific task or context  Much disagreement– Domain General vs. Domain Specific  Domain General= Piaget theory- particular stage means child thinks at that level across domains  Domain Specific= suggest there is greater flexibility in thinking across different tasks and different domains (accounts for 4yr old experts on dinosaurs)  Research contradicts assumption that children exhibit only stageappropriate thinking  Cognitive development is internal – internal maturational processes, rather than environmental context/events determine cognitive development  Research provides evidence of environmental influences (particular experiences, training, environmental factors) effect child performance on Piagetian tasks  Even adults and adolescence often do not show formal operational thought- tend to think associatively rather than logically  Piaget later modified theory (19720 to acknowledge formal operations may be more a product of domain expertise (experience) rather than maturational processes  Piaget’s theory as a Competence Theory (theory of what people at various ages are maximally capable of doing) vs. Performance Theory (a theory of what people of various ages naturally do in daily lives)  Way we can potentially think may not be the way we usually think (and visa versa) Neo-Piagetian Approach     Neo means ―new‖ –refers to those who came after Piaget but start from his Stages and Ages theory Most Neo-Piagetian Psychologists:  Accept Piaget’s broad notion of stages of cognitive development  But include non-Piagetian ideas  Take more into account domain specificity (different rates of intellectual growth for different areas of knowledge)  Tend to concentrate on the scientific or logical aspects of cognitive development  Retain some ties with concept of cognitive development occurring through equilibration Perhaps most famous: Robbie Case  Case’s cognitive development theory based on maturation & stages (ala Piaget) but also includes increases in efficiency (information processing) Also, another group suggest a 5th stage of cognitive development  Post-Formal or Dialectical Thinking Stage : dialectical thinking recognizes that for much in life, there is no one, final, correct answer but consider and chose among alternatives (with other choice having benefits, too), also take into account sociocultural context in which decisions are made Vygotskyan Approach Sociocultural Theory     Lev Vygotsky (1896- 1934) Russian Psychologist (also had degree in law, was working on medical degree, wrote books on philosophy, art criticism and literary research) Considered 2nd only to Piaget in terms of influential theory of cognitive development– work ―re-discovered‖ in 1960-70s with cognitive revolution Theory based on opposite foundation from Piaget:   Piaget: cognitive development proceeds from inside out – emphasizes biological (development before learning) Vygotsky: cognitive development proceeds from outside in– social influences (not biological) are key (so learning before development)–The mind is inherently social! Vygotskyan Approach Sociocultural Theory  Two important conceptions for outside in development:  Internalization:  The absorption of knowledge from context  Children’s learning occurs through the child’s interactions within the environment, which determines what the child internalizes mentally Zone of Proximal Development (ZPD):   Skills Mastered Skills a child is Beginning to learn and can perform with help the range of potential between a child’s observable level of realized ability (performance) and the child’s underlying internal capacity (competence) which is not directly obvious ZPD Skills beyond the child’s current capabilities Vygotskyan Approach Sociocultural Theory  Important assertion:  Need to not only focus on how children think but how we measure them  Real display of cognitive development is dynamic (part of social interaction= give and take)  Examiner serves as both teacher and tester– can provide mental Scaffolding (support) to help move child from where they are in problem solving to the next step  Research supports that scaffolding helps advance children to next level of understanding Vygotskyan Approach Sociocultural Theory    Development of thinking is from society to the individual (children learn to talk from others, and thus learn how to think through inner speech) 3 Stages of Conceptual Development  Formation of thematic concepts: relationship between objects is important (classify by theme- book & shelf)  Formation of chain concepts: classification criteria changes throughout the process (first few blue blocks, then notice a triangle block, start picking up triangles, pick up yellow triangle, start sorting yellow blocks)  Formation of abstract concepts: similar to adult concept formation Theory of Language  Social (0-3yrs) — controls the behavior of others, expresses simple thoughts and actions  Egocentric (3-7yrs) — bridge between internal and external speech serves to control behavior but spoken aloud  Inner (7+yrs) — self-talk that makes possible the direction of thinking, language involved in all higher mental functioning Information Processing Approach     Focus on understanding cognitive development in terms of how people at different ages process information (encoding, decoding, transferring, combining, storing, retrieving)  Q = how do processes, strategies and ways of representing/organization change over time? Not as comprehensive or well-integrated as Piagetian or Vygotskyan theories Adopt either domain-general or domain-specific theoretical foundation  Domain-general= attempt to describe how general principles of information processing apply/are used across a variety of cognitive functions  Most focus on: encoding, self-monitoring, use of feedback  Domain-specific= emphasize role of the development of competencies and knowledge in specific domains (argue most development is this kind)  Example: Theory Theory– small # of frameworks ground understanding Research suggests with age, people:  More fully encode many features of environment  Organize information more effectively  Increasingly can integrate and combine information in more complex ways, forming more elaborate connections with prior knowledge  Just know more, can call on increasingly large information stores Information Processing Approach  Selective Attention:   Evidence suggests children have less control than adults Facial Attention    Sensitive to mothers face within hours Infants spend more time looking at patterns than solids. Infants spend the most time looking at a drawing of a human face. Infants looked more intensely at the actual face. Very young children first focus on facial contours, then the eyes by 2 months   Information Processing Approach  Memory Skills:   Research suggests with age = have greater processing resources which facilitates greater attention and working memory capacity  Neurological explanation for increase in processing speed during childhood= greater mylinization of axons speeds neural processing  Faster processing means hold more chunks in WM  Research suggests with age, develop better metacognitive skills (better self-monitoring and modification of own cognitive processing) Research suggest adults naturally use memory aids, particularly rehearsal and that this develops with age (young children often do not rehearse)  One conclusion suggested is that the difference between children and adult memory is not basic mechanisms but in learned strategy (particularly rehearsal)  Research suggests with age, greater ability to recognize and utilize higher-order relationships that link environmental events  Able to organize information into increasingly large and complex chunks Response times decrease from 7 - 12 years of age--Consistent across several different types of tasks Information Processing Approach  Memory Skills of Infants:   Considerable recent research suggest infants have memory for events  Imitation: mimicry  Operant Conditioning: goal directed behavior for positive outcome Research suggests infants can form concepts  Habituation: attention decreases for non-novel events  Recovery: tendency for a second stimulus to arouse new interest (often used to test whether infants can discriminate between stimuli)  Conceptual categories/abstract prototypes develop before language (particularly for faces)   BUT early memories not same kind as adult memories  Childhood amnesia until 39-42 months Research suggests age 10-30 produce most autobiographical memories  Suggests children at very young age obtain/use sophisticated story schemata (abstract memory structure) Information Processing Approach  Quantitative Skills:  Research suggests—     Even pre-linguistic infants have some fundamental notion of quantity with small numbers Young children appear to build on this fundamental knowledge to apply more abstract math in counting, adding, subtraction Young children derive abstract rules from experience Context effects (problem wording to cultural environment) greatly influences mathematical learning beyond development of informal strategies Information Processing Approach  Imagery:  Some researchers (particularly Kosslyn) suggest that children rely on imagery more than adults    If a child does not have answer stored as proposition, will use imagery to answer Since adults store more propositions, need to rely on imagery less Research suggests that adults tend to store information as semantic propositions whereas children use imagery  Can American Idol contestants sing behind the judges? Information Processing Approach  Visiospatial Skills:  Research suggests:  With older children/adults can mentally rotate more quickly than young children, although all can rotate familiar object more quickly than unfamiliar object    May be a matter of processing speed May be younger children must rotate whole object, older rotate more analytically (only rotate part) May be a function of practice and automaticity  Older adults (55-71) respond slower than younger adults (18-23) on mental rotation tasks, but same on image scanning tasks  Suggests age may effect some types of mental imagery more than others Prenatal Development The Growing Fetus Fertilization 30 Hours 6 weeks 4 months Embryogenesis: process by which an embryo is converted from a fertilized cell to a full-term fetus Prenatal Development  1st month    zygote divides & becomes the blastocyst cells detach and form embryonic disc cells of embryonic disc differentiate into 3 layers    ectoderm - will become nervous system endoderm - will become respiratory & digestive organs mesoderm - contributes to nervous system development Prenatal Development    ectoderm becomes neural plate ridges appear on neural plate which then fuse and form neural tube and neural crest top of tube thickens and eventually develops into brain while the rest develops into spinal cord Prenatal Development  Top part of neural tube thickens and becomes    forebrain midbrain hindbrain  By 2 months, can differentiate cortex, thalamus, hypothalamus, cerebellum Prenatal Development    Neurogenesis: the production of brain cells brain cells  By 4 ½ months, develop over 250,000 per minute.  Several points where over 50,000 brain cells are formed every second.  By the twentieth week--over 200 billion neurons created. Later--massive Apoptosis (programmed cell death, also called neural pruning) occurs  During the third trimester, only fifty percent of those cells remain  Surviving 100 billion neurons are the healthy cells-- ready to aid the growth and development of the newborn child. Billions of synapses are created in the womb during the process of synaptogenesis: process by which the functional circuits in the brain get organized  Early overproduction of neurons and neural networks guarantees that the young brain will be capable of adapting to virtually any environment into which the child is born.  Following birth, most new synapses come by way of one’s experiences. Postnatal Development   No new neurons grow after birth  Latest research suggest may be exceptions– hippocampus & olfactory bulbs Increase in size and connections of existing neurons  Axons grow longer  Arborization: Dendrites grow more dense, bushy  More synapses formed The growth of glial cells Increase in myelinization of axons brain size increase due to    Postnatal Development  At birth:    Brain stem fully developed Some mid-brain areas still to develop more (like hippocampus) Cortex still largely immature  Most rapid= development of sensory and motor cortex  Followed by development of association cortex areas, particularly frontal lobe  recent research correlates infant physiological growth of frontal lobe to significant cognitive growth outlined for this period by Piaget  Later:   Frontal lobe development linked later to reading skill– also, differences in reading correlated to hemispheric specialization Latest research on Lateralization/EEGs shows:  Right hemisphere-- continuous, gradual development in with age  Left hemisphere– appear to be abrupt shifts through early adulthood  Development shifts between hemispheres (development spurt more active in one hemisphere, then switches to other hemisphere)  Anterior portion of frontal lobes appear to regulate synaptic re-organization of posterior areas  thus, not only left/right changes but also front/back Postnatal Development  Effect of cognitive experience   enriched environments affected rats  performed better at maze learning  had thicker regions of neocortex  dendritic branching was greater  increased blood flow to areas of brain similar effects found in humans  MEG measures found musicians had larger area of brain representing left hand (used for finger board of stringed instrument) Neurocognitive Development  Experience DOES affect post-natal brain development  A toddler's brain has twice as many connections among its 100 billion neurons as the brain of a fully matured adult  All new learning = neurons respond by reaching out to one another in an elaborate branching process that connects previously unaligned brain cells  creating complex neural circuits results in formation of dense neural forests that are the physiological byproducts of stimulation and learning  Sensory, Motor, Cognitive experience provide Functional Validation: for neural systems to become fully functional, stimulation is required  Use it or lose it– with experiences and neural activation, best neural circuits get strengthened– cells not used get pruned  A fine-tuning of a child’s emerging talents occurs between three and six years of age.  At approximately age five or six, the brain has reached 90-95% of its adult volume and is four times its birth size.  Ages three to six are the years during which extensive internal rewiring takes place in the frontal lobes, the cortical regions involved in organizing actions, planning activities and focusing attention  Some researchers suggest the development of the cerebral cortex can be reduced by as much as 20% under impoverished conditions many brain structures under-developed (seen in animals, potentially same in humans).  Suggests diminishing learning opportunities reduces the quantity of neural networks, which decreases one’s ability to learn in the future Postnatal Development  Experience DOES affect post-natal brain development  By the process of Neural Plasticity (the brain’s ability to undergo physical, chemical, and structural changes as it responds to experiences and to one’s environment) the number and density of functional neural pathways will be determined by the environmental experiences one encounters.  The brain constantly modifies the connections among its one trillion brain cells that are consistently impacted by incidents processed consciously and unconsciously by the brain.  Reason we are all different!  Neural Plasticity – more plastic younger but even adult brains plastic  Brain constantly changing! Cognitive Development of Adults  Debate as to whether cognitive capabilities decline:  Research suggests decline in fluid information processing (abstract symbols/complex problem solving)  Increases 20s, 30s, 40s, then slowly decreases  Rate of decline varies across people VS.      Research suggests crystallized abilities continues to increase (store of declarative knowledge)  Means long-term memory and structure/organization of knowledge is preserved across life span Research suggests older adults may be more effective self-monitors Research shows when task performance is based more on accuracy than speed, older adults do well (carefulness and persistence) Others question evidence on decline– suggest problems with measureconfused with other changes Most Important: at all times throughout life span– brain has plasticity always chance of improvement Cognitive Development of Adults  Three Basic Principles:  Decline of fluid information processing (abstraction/ complex problem solving) in late adulthood is balanced by stabilization and even advancement of crystallized abilities (large stored declarative knowledge which keeps increasing)-- well-practiced and practical mental functioning related to stored knowledge  Many adults find ways to compensate for later decline so actual performance unaffected (forgetful= leave yourself notes)  Despite decline, sufficient reserve capacity allows some temporary increase in performance (especially if motivated)  When adults lose speed and physiology-related efficiency in information processing, often compensate with other knowledge and expertisebased information processing skills