Lifespan Development Lecture Notes PDF

Lifespan Development examines patterns of: -​ Growth ​ Physical ​ psychological -​ Change ​ Ex: improving/losing existing skills -​ Stability ​ Ex: characteristics, abilities Age-graded influences: biological and environmental influences that are...

Lifespan Development examines patterns of: -​ Growth ​ Physical ​ psychological -​ Change ​ Ex: improving/losing existing skills -​ Stability ​ Ex: characteristics, abilities Age-graded influences: biological and environmental influences that are similar for individuals in particular age group -​ Ex: puberty and menopause, entry into formal education at around age 6 History-graded influences: biological and environmental influences associated with particular historical moment includes cohorts -​ Ex: cohort effects, wars, economic depressions, terrorist attacks, epidemics, famines Sociocultural- graded influences: social and cultural factors present at particular time for a particular individual depending on such variables -​ Ex: ethnicity, social class, subcultural membership (white and affluent versus minority group and impoverished) Non-normative life event: atypical events that occur in a particular person’s life at a time when such events do not happen to most people (like tragic events) Key Debates in Lifespan Development Continuous change vs. discontinuous change -​ Continuous change: gradual development, quantitative, a matter of degree (ex: height) -​ Discontinuous change: distinct stages, qualitative, changes in thinking Ciriti al periods vs. sensitive periods -​ Critical period: the absence/presence of certain kinds of environmental influences to produce permanent, irreversible consequences for the developing individual ​ Ex: rubella in the first 20 weeks of pregnancy → potential blindness, deafness, and heart defects, but in the 30th week, damage is unlikely -​ Sensitive period: the absence of particular environmental influences may hinder development ​ Possible for later experiences to overcome the earlier deficits ​ Susceptible to certain kinds of stimuli- optimal period  ​ Ex: music & sports training Lifespan approach vs. particular periods approach -​ Particular periods approach: infancy and adolescence are the most important parts -​ Lifespan approach: the entire life is important ​ Developmental growth and change continue during every part of life ​ Social environment ​ Gains (ex: vocabulary) and losses (ex: reaction time) Nature vs. nurture -​ Nature: hereditary information, traits, abilities, capacities ​ Maturation: the predetermined unfolding of genetic information -​ Nurture: influences of the environment ​ Biological: the impact of a pregnant mother’s use of cocaine on her unborn child, the amount and kind of food available to children ​ Social: parents discipline style, the effects of peer pressure on an adolescent ​ Societal-level: socioeconomic status -​ The interaction of genetic and environmental factors ​ Ex: intelligence Universal vs. context-specific development -​ “One right way to develop” vs multiples ways in which development occurs Theories of Child Development: Historical Perspectives John Locke: tabula rasa (1632-1704) Jean-jacques rousseau: innate sense of justice (1712-1778) James mark baldwin: theory guides experimentation (1861-1934) The Biological Perspective Natural selection (Darwin) -​ An ongoing process in nature that results in survival of those organisms that are best adapted to their environments Maturation theory (Arnold Gesell) -​ Child development reflects a specific and pre-arranged scheme or plan within the body -​ Without interference from adults & according to the predetermined developmental timetable Ethnological theory -​ Evolutionary perspective: adaptive behaviours ​ Survival value ​ Crying→ elicits caregiving from others -​ Critical periods -​ Imprinting- cannot occur if no moving object within about a day of hatching– emotional bond with the mother -​ Attachment The Psychodynamic Perspective -​ Sigmund freud (1856-1939) -​ Theory of personality -​ Components of personality ​ ID: primitive ​ Ego: practical/rational ​ Superego: moral agent -​ Psychosexual theory ​ Individuals instinct vs. societal norms ​ Libido ○​ Motive for physical pleasure ○​ Libido shifts to different parts of the body Psychosocial Theory -​ Erik erickson (1902-1994) -​ Emphasis on social and cultural influences -​ Journey to adulthood is fraught with obstacles Early Learning Theories The Learning Perspective -​ John B. Watson -​ Strong emphasis on environmental influences -​ Endorses locke’s tabula rasa theory -​ “Little albert” experiment Classical conditioning -​ Ivan pavlov (1849-1936) ​ Famous dog experiment ​ Unconditioned & conditioned stimuli ​ Unconditioned & conditioned response Operant Conditioning -​ B.F Skinner (1904-1990) ​ Focuses on outcome of behaviour ​ Reinforcement ○​ Reinforcement: to increase the likelihood of a behaviour ○​ Punishment: to decrease the likelihood of a behavior Social cognitive theory -​ Albert bandura (1925-2021) ​ Imitation or observational learning ​ Social cognitive theory ​ Self-efficacy Development perspective -​ Jean piaget (1896-1980) ​ Infants, children, and adolescents ​ Children are naturally motivated to make sense of the physical and social world ○​ Little scientists ​ ​ 4 distinct stages in cognitive development ○​ Sensorimotor (0-2) ○​ Preoperational thought (2-6)  ○​ Concrete operational thought (7-11) ○​ Formal operational thought (adolescence and beyond) Contextual perspective -​ Lev vygotsky ​ A sociocultural approach to cognitive development ​ Culture ○​ Tools: language, symbols, customs ○​ Provides the context in which a child develops ​ Important influence from infancy to adolescence Ecological systems theory -​ Urie bronfenbrenner (1917-2005) ​ Various environmental influences ​ Environment is a series of embedded systems ○​ Microsystem ○​ Mesosystem ○​ Exosystem ○​ Macrosystem ○​ Chronosystem Other approaches to child development -​ Informed processing theory ​ Human mind is similar to a computer  -​ Evolution theory ​ Evolution shapes behaviour and characteristics ○​ Survival of infants and children ○​ Grandparents-grandchild relationships: investment in the survival of one’s own kin -​ Developmental psychopathology ​ Broad unified understanding of how abnormal development can occur Research in Child Development -​ Decide how to measure the topic of interest -​ Design the study -​ Ensure the proposed research respects the rights of participants -​ Share the results with others (once the study is complete) Measurement in Child Development Research 1.​ Systematic observation: naturalistic and structured 2.​ Sampling behaviour with tasks 3.​ Self reports: questionnaires or interviews 1.​ Systematic observation -​ Watching children and carefully recording what they do or say -​ Naturalistic -​ Structured 2.​ Sampling behaviour with tasks -​ Create tasks that are thought to sample the behaviour of interest -​ Ecological validity? 3.​ Self-reports -​ People’s thoughts or ideas about questions related to a topic of interest -​ Who'll answer my questions? ​ Child ​ Parents ​ Teachers ​ Daycare providers  -​ Reliability -​ Validity ​ Convergent validity (positively correlated) vs divergent validity (not correlated) Representativeness -​ Samples of children who participate in research should be representative of the population of interest -​ Psychology of WEIRD -​ Psychology research in canada ​ Socially diverse ​ Geographically large Increasing Sample Diversity: -​ Be mindful of historical patterns of oppression and inequality -​ Adopt a racially diverse team science approach -​ Generate diverse samples -​ Consider the influence of multiple identity groups on human experience (intersectionality) -​ Promote the translation of knowledge from the laboratory to the field Design & Management -​ Design ​ Correlational ​ Experimental -​ Measurement ​ Longitudinal  ○​ Microgenetic ​ Sequential ​ Cross-sectional Designs for Research: Inferential statistics Correlational studies: ​ Relations as they exist in the real world ​ Associations between variables ​ Correlation coefficient, r, -1.0 to + 1.0 ​ Not a measure of causation Three interpretations of a correlation coefficient 1.​ The first variable causes the second variable 2.​ The second variable causes the first variable 3.​ Neither variable is caused by the other; both are caused by a third variable that was not measured in the study -​ Comparing variables/means to see if there are differences between them ​ Ex: if an average of 10 inches of rain falls in june one year and an average of 12 inches of rain falls in june the next year -​ P-value: probability of obtaining a particular measurement if, in fact, no real difference existed between the conditions being observed ​ Some journals banned the use of p-value, but require the use of descriptive statistics and effect sizes Experimental studies -​ Systematic way of manipulating the key factors that an investigator thinks causes a particular behaviour ​ Independent variable ​ Dependent variable ​ Mediator variable ​ Moderator variable ​ Random assignment Field experiments -​ Manipulate independent variables in a natural setting so that the results are more likely to be representative of behavior in real world settings  -​ Ex: providing child development courses to half of the caregivers & comparing with the other half Methods for Studying Development Longitudinal study -​ Measuring individual change -​ Ex: language development Microgenetic study -​ The variables of interest are measured in the same research participants repeatedly over a short period of time, such as days or weeks, in order to capture an aspect of rapid development change Sequential design -​ The variables of interest are measured repeatedly over time in the same groups of research participants, with each group having been born in a different time period -​ Ex: following a group of 5 year olds, a group of 10 year olds, and a group over 15 year olds over a five year period, measuring all children in each group on the same variables -​ Cohort effects: the effect of a particular event, culture, or historical experience on a particular group of children Issues with longitudinal studies: -​ Practice effects -​ Attrition Cross-sectional studies -​ Developmental changes are identified by testing children of different ages at one point in their development -​ No more practice effects or attrition but there is the continuity of development and cohort effects Ethical responsibilities -​ Minimize the risks to research participants ​ Methods that have the least potential for harm or stress for research participants ​ Cost benefit analysis ○​ Reasonable risk -​ Describe the research to potential participants ​ Informed consent vs assent -​ Avoid deception if possible  -​ Keep results anonymous or confidential Child development research and family policy -​ Laws and regulations that directly or indirectly affect families with children -​ Even more important as families are changing ​ Traditional families: stay at home more & working dad ​ Families with a single parent ​ Families in which both parents are employed outside the home ​ Blended families that include stepparents and step/half siblings Evidence based practice -​ An approach to practice in health services using those methods if intervention and assessment that have been demonstrated, through the best available research evidence, to be effective Genes -​ Not deterministic but probabilistic -​ Interact with the environment Biology of Heredity -​ Ectogenesis: fertilization of an egg outside the uterus -​ In-vitro fertilization ​ Mixing sperm and egg together in a lab dish and then placing several fertilized eggs in the mother about 24 hours later, with the hope that one will become implanted in the wall of her uterus -​ Autosomes: first 22 pairs of chromosomes -​ Sex chromosomes: 23rd pair ​ X from egg ​ X or Y from the sperm -​ Deoxyribonucleic acid (DNA): code for specific genes -​ Genotype: one’s complete set of genes -​ Phenotype: one’s physical, behavioral and psychological gestures ​ Genetic and environmental factors Single gene inheritance -​ 46 chromosomes- about 20/25,000 genes -​ Each gene has a pair of allele ​ Specific form of a gene, homozygous or heterozygous -​ Homozygous: inherited identical versions of the gene from both parents -​ Heterozygous: inherited different alleles of a gene  ​ Dominant alleles ​ Recessive alleles ​ incomplete dominance Behavioural Genetics -​ The study of the inheritance of behavioural and psychological traits -​ Relationship between genes and complex behavioural and psychological traits is a difficult area of study -​ Not either-or traits but represent a broad range of outcomes along a continuum of possibilities -​ Polygenic inheritance: when phenotypes reflect the combined activity of many separate genes -​ Many psychological traits involve countless genes Nonshared environmental influences -​ Experiences and circumstances within a family that contribute to siblings being different -​ It usually affects each child in a unique way -​ Each child is likely to have different experiences in daily family life -​ Ex: parents might be more affectionate with/use more punishment with/have higher expectations from one child than another Abnormal chromosomes -​ Disorders are caused by: ​ Too many, too few, or damaged chromosomes ​ Missing or extra sex chromosomes ​ Down syndrome ○​ Develop normally during the first few months ○​ Later - delay in cognitive & behavioral development ○​ Support system - preschool - programs to prepare for school Genes, the environment and behaviour -​ Influence of genes on behaviour is always direct -​ By making behaviours more or less likely -​ Ex: no gene for alcoholism, but genes regulate how the body breaks down alcohol that is consume -​ Some people become nauseated because their bodies cannot break down alcohol and are therefore less likely to become alcoholics -​ Behavioural consequence depends on the environment in which genetic instructions are carried out ​ Genetic reductionism: reducing the cause of environmental conditions and behaviours exclusively to genes ​ Genetic change over time is more the product of complex evolutionary processes Prenatal development -​ Begins during ovulation -​ Fertilization occurs when egg penetrated by a sperm -​ Zygote → embryo → fetus —> baby 1.​ Period of the zygote: 0-2 weeks -​ Egg is fertilized, zygote becomes implanted in wall of uterus -​ Cluster of cells in the center of the zygote becomes the baby -​ Period of rapid cell division 2.​ Period of the embryo: 3-8 weeks -​ Period of rapid growth, most body structures begin to form -​ Ectoderm: hair, outer layer of skin, nervous system -​ Mesoderm: muscles, bones, circulatory system -​ Endoderm: digestive system and lungs -​ Embryo rests in the amnion filled with amniotic fluid -​ Umbilical cord joins to the placenta -​ Growth during the embryonic period is: ​ Cephalocaudal: top extending down, head to the body ​ Proximodistal: center extending out, arms/legs to the hands/feet  3.​ Period of the fetus: 9-38 weeks -​ Huge increase in size, most body systems begin to function -​ Recognize sounds, react sounds, food Influences on prenatal development -​ Nutrition -​ Stress -​ Mothers age ​ Optimal age between 25-34 years ​ Younger mothers: infectious diseases ​ Older mothers: mental disorders, heart diseases, circulatory diseases, and congenital malformations -​ Teratogen: any agent that disrupts normal pregnancy -​ Thalidomide -​ Diseases -​ Environmental hazards, toxins through food, water, air or added to products such as paint, plastic -​ Dangerous drugs -​ Fetal alcohol spectrum disorder (FASD) ​ Intellectual delay and poor social judgment, limited motor skills, language, and visual-motor coordination ​ Small head, a thin upper life, a short nose, and widely spaced eyes How teratogens influence prenatal development -​ The impact of teratogen depends upon the genotype of the child -​ The impact changes over the course of prenatal development -​ Each teratogen affects a specific aspect of prenatal development -​ Damage from teratogens is not always evident at birth but can appear later in life Prenatal diagnosis and treatment -​ Diagnosis ​ Ultrasound, amniocentesis, and chorionic villus sampling (CVS) -​ Treatment ​ Maternal-fetal medicine, fetal surgery and gene therapy Labour and delivery Stage 1: begins when the muscles of the uterus contract and ends when the cervix is fully enlarged Stage 2: baby is pushed down the birth canal Stage 3: placenta is expelled Approaches to childbirth -​ C-section: surgical incision in mothers abdomen -​ Childbirth classes -​ Doula: non medically trained support person -​ Obstetrician: specializes in female health and reproduction -​ midwife: not a physician, but trained to assist in normal delivery Birth complications -​ Complete oxygen deprivation (anoxia) -​ Detachment of placenta from uterine wall (placental abruption) -​ Reduced supply of oxygen (hypoxia) -​ Born less than 38 week gestation (prematurity) -​ Babies who are substantially smaller at birth (small for date infants) Newborn States -​ Alert inactivity: the baby is calm, with eyes open and attentive; the baby looks to be deliberately inspecting the environment -​ Walking activity: the baby’s eyes are open, but they seem unfocused; the baby moves arms or legs in bursts of uncoordinated movements -​ Crying: the baby cries vigorously and usually makes agitated but uncoordinated motions  -​ Sleeping: the baby’s eyes are closed and the baby drifts nacl and forth from periods of regular breathing and stillness to periods of irregular breathing and gentle arm and leg motion Sudden Infant Death Syndrome -​ “Crib death”: when a healthy baby dies suddenly, usually during sleep, for no apparent reason ​ Premature birth, low birth weight, smoking parents ​ When a baby sleeps on its stomach ​ During winter - overheated from too many blankets and too heavy sleepwear ​ Cushiony surfaces, clothing, pillows, stuffed toys, blankets which do not allow proper circulation of air around a baby’s face ​ Abusive head trauma and shaken baby syndrome ​ In Canada 3 babies peer week die from SIDS Postpartum depression -​ Half of all new moms feel some irritation, resentment, and crying after giving birth -​ 10-15% feel more severe postpartum depression, low self worth, disturbed sleep, poor appetite, apathy -​ Children of depressed mothers are at an increased risk of developing depression and behavioural problems Features of human growth -​ Rule of thumb: ​ Triple the birth weight round 1 year ​ Boys achieve half their adult height by 2 years and girls by 18 months -​ Follows the cephalocaudal principle ​ Disproportionately large head and trunk -​ Muscles become longer and thicker -​ Baby fat- before birth ​ Leaner in preschool years, acquire fat again in elementary school years ​ Obesity risk - not noticeable until the age of 4 -​ Cartilage: a soft, flexible tissue → bone ​ During the embryonic period, the middle of the tissue turns to bone ​ Before birth, ends of cartilage turn to bone ​ Shortly before birth, cartilage is replaced by bone Variations on the average profile -​ Secular growth trends: generational changes in physical development that are related to environment  ​ Nutrition, healthcare, better living conditions -​ Average and normal are not the same, normal can vary greatly Mechanisms of physical growth 1.​ Heredity influences adult height -​ Fraternal twins - r ~.50 -​ Identical twins - r >.90 -​ Two parents contribute equally - average of 2 parents’ height and childs height: r ~.70 2.​ The pituitary gland secretes growth hormone -​ Usually at sleep (sometimes after exercise) -​ Muscles and bones grow -​ Low amount of GH - dwarfism (120-135cm height, normal proportions) -​ Can be treated with injections of growth hormone 3.​ The thyroid gland releases thyroxine -​ Development of nerve cells & cognitive development -​ Some research on rats: maternal alcohol consumption → decreased thyroid function → cognitive delays 4.​ Nutrition is particularly important during infancy when growth is rapid -​ 40% energy devoted to growth -​ 100 and 120 calories per kilogram of body weight per day Nutrition -​ Breast milk is recommended by the canadian pediatric society for babies up to 6 months -​ barriers/facilitators to breastfeeding? -​ Donor breast milk? -​ Bottle feeding -​ Introduce one food at a time -​ Allergies -​ At 2 years, growth slows and children can become picky eaters Challenges to healthy growth -​ malnutrition ​ Homelessness and poverty ​ Especially damaging in infancy ○​ Cognitive development ○​ Intelligence tests ○​ Attention in school ​ Prevention: food availability, nutrition education, and behavioral change -​ Diseases  ​ About 45% of all child deaths are related to malnutrition ​ In canada, asthma there is an increasing prevalence -​ Prevention: safe water, vaccines, improved health care, and changing habits -​ Accidents ​ After 1 year children are most likely to die from accidents ○​ Most common: motor vehicle accidents ○​ preventionL infant car seats, proper use of seat belts ​ Drowning ​ Suffocation The developing nervous system: a basic nerve cell -​ Cortex: about 10 billion neurons -​ Cerebral hemispheres: right and left halves of the cortex -​ Left hemisphere: ​ To produce and understand language, to reason and to compute -​ Right hemisphere: ​ Artistic and musical abilities, perceptions of spatial relationships, and ability to recognize faces -​ Corpus callosum: a thick bundle of axons joining left and right hemispheres Developing brain -​ Brain originates in the neural plate (group of cells formed about 3 weeks after conception -​ At 10 weeks - production of neurons begins -​ At 4 months - myelination -​ From synaptogenesis to synaptic pruning ​ Downsizing Structure and function -​ Measurement of electrical activity ​ EEG - measure pattern of brain waves ​ Using a brain function should create a distinctive pattern in that region -​ Measurement of activation in the brain ​ FMRI - track the flow of blood in the brain ​ PET - use of glucose in the brain Frontal cortex -​ Brain regions specialize early -​ “Flexible” or neuroplastic brain organization -​ Frontal cortex regulates: ​ Deliberate, goal oriented behaviours ​ Personality ​ Emotions ○​ Left frontal cortex: approach emotions ○​ Right frontal cortex: avoidance emotions ​ Low quality care Motor skills -​ Coordinated movements of the muscles and limbs ​ Crawling, walking, writing -​ locomotion ​ Moving about in the world ​ Newborns - relatively immobile -​ Fine motor skills ​ Small muscle groups (ex: grasping, holding, and manipulating objects) -​ Gross motor skills ​ Large muscle groups (running, throwing, and jumping) Infant reflexes -​ Unlearned response triggered by a specific form of stimulation -​ Preparation for world interaction -​ Some reflexes are important to survival ​ Rooting and sucking -​ Some protect the newborn ​ Blink and withdrawal -​ Some are foundations for later motor behaviour ​ Ex: stepping reflex: babies who are provided with opportunities to practice the stepping reflex learn to walk earlier Locomotion -​ Individual variability -​ Not just natural maturation ​ Environmental factors -​ Dynamic systems theory: motor development involves many distinct skills Posture and balance -​ To master walking, infants must acquire distinct skills of: ​ Standing upright ​ Maintaining balance ( with a big & heavy head) ​ Stepping alternatively ​ Using perceptual information to evaluate surfaces -​ Baby walkers ​ Banned in canada Fine motor skills -​ Reaching and grasping ​ Around 4 months ○​ Reaching: random moves to reach an object ○​ Grasping: just fingers to hold ○​ Coordination: motion of hands are not coordinated ​ As they grow old ○​ Reach9ing: less movement to reach an object  ○​ Grasping: grasp finger foods - about 6 months ○​ Coordination: eye hand coordination -​ Handedness ​ Study with infants and toddlers ○​ Equal use of both hands around 9 months ○​ Emergence of a preference at 13 months ​ Stronger and consistent preference during preschool years ​ Established before kindergarten -​ Role of heredity ​ Cultures favour right handedness Sensory and perceptual processes -​ smell ​ Mothers smell, their amniotic fluid ​ Honey or chocolate - relaxed and content facial expression ​ Rotten eggs or ammonia - frown or turn away -​ Taste ​ They have a sweet tooth ​ Changes in the taste of breast milk - nurse more after mother consumes vanilla -​ Touch ​ Pain experience - high pitched cry ​ Pain causes stress - neurological outcomes Hearing -​ A fetus can hear at about 7 or 8 months gestation -​ Auditory threshold: the quietest sound that a person can hear -​ Auditory localization: infants use sounds to judge the distance and location of objects ​ Study: shaking a rattle 15 cm vs 60 cm away in a dark room ​ 7 months old reach for the rattle shaken 15 cm away Seeing -​ Awake time: looking around like scanning or focusing on an object -​ Visual acuity ​ Patterned stimuli over plain, non patterence stimuli ​ Newborns and 1 month olds see at 6 metres what normal adults see at 60 to 120 meters -​ Perceive colours by 3 or 4 months -​ Master perceptual constancies early - around 4 months ​ Size, colour constancy, shape constancy Depth -​ Visual cliff ​ Babies who can crawl ​ Babies 1.5 months old ○​ Cant crawl ○​ Reduced heart rate on the deep side Cognitive development -​ Primarily as a result of repeated stimulation to sensory pathways and synaptic connections in the brain -​ Early levels of stimulation → later levels of capacity in terms of both cognitive ability and biological functioning -​ Piaget: children's cognitive development arose out of constant interaction between their level of maturation and their experiences in the world -​ Other behaviorists: solely out of children’s experience with the world Piaget’s theory -​ Children naturally curious -​ Schemas: psychological structures that organize experience ​ Mental categories or conceptual models of interrelated events, objects, and knowledge that children build as they gain experience with situations, people, and objects around them ​ Start with own actions & controlling their bodies -​ Assimilation: incorporate new experiences into existing schemas ​ Grasping schema work not only on favourite toy but also on other small objects -​ Accommodation: change schemas based on experience ​ Some objects must be lifted with two hands and some cant be lifted at all Piaget’s Sensorimotor Stage (1 of 2) From birth to 2 years – rapidly changing perceptual and motor skills Substage 1: Exercising Reflexes (birth-1 month). – Sucking a nipple Substage 2: Learning to Adapt (1-4 months). – Primary circular reaction: recreating a pleasing event with the body – accidentally discovers it.  – Thumb sucking Substage 3: Making Interesting Events (4-8 months). – Secondary circular reaction: Novel actions that are repeated with objects. – Shaking a toy to hear it rattle Substage 4: Using Means to Achieve Ends (8-12 months). – The onset of deliberate, intentional behaviour – Moving an obstacle to reach a toy Substage 5: Experimenting with objects (12-18 months). – Tertiary circular reaction: repetition of old schemas with objects of different kinds (i.e. trial-and-error) – Shaking different toys to hear the sounds they make, throwing objects to see what happens Substage 6: Mental Representation (18-24 months). – Deferred imitation: imitate actions that they have observed at an earlier time – the start of make-believe play The Child as Theorist (1 of 2) Young children: – develop theories:Naïve physics – organize knowledge about the properties of objects and living things:Naïve biology ▪ E.g. objects cannot move “through” other objects (3-4 months), cannot float in midair without support (1 year) ▪ Look longer at moving objects that violate their theories (e.g., a ball that somehow rolls “through” a solid wall), suggesting that infants are surprised ▪ E.g. cat can drink water, but not apples. ▪ animate vs. inanimate objects Information processing theory -​ People and computers are both symbol processors -​ Mental hardware: neural structures → sensory, working, and long term memory -​ Other forms of memory: procedural, semantic, autobiographical or episodic memory Habituation -​ Orienting response: a physical reaction to a strong or unfamiliar stimulus  ​ Physical reacts (starts), looks at the stimulus, experiences changes in heart rate and brain wave activity → indicate that the person noticed the stimulus -​ Habituation: a state of diminished responding to a stimulus as it becomes more familiar -​ Dishabituation: a state of re-orientation, when a person becomes aware of a stimulus to which the person previously had habituated -​ Functions of orienting response and habituation -​ Classical conditioning: a neutral stimulus elicits a response that was originally produced by another stimulus ​ Ex: an infant might smile when she hears the family god's excited bark because she knows the dog is coming to play with her -​ Operant conditioning: focuses on consequences and reoccurrence of behaviours ​ Ex: when a baby smiles, an adult might hug the baby in return, making the baby more likely to smile in the future -​ Imitation: watching others behave ​ Ex: a toddler might imitate an adult waving a finger back and forth; or copy another infant who knocks down a tower of blocks How infants remember -​ Infantile amnesia: inability to remember events from early in life Understanding the World Babies experience daily variation in quantity; toys, food, etc. Understanding numbers – After habituating to a certain number of objects in pictures, look longer at the new picture with a different number of objects Test of quantity – 6-month olds distinguish between objects in a 1:2 ratio but not a 2:3 ratio – 10-month olds discriminate at a 2:3 ratio but not a 4:5 ratio Exploring the Environment Egocentric frame of reference – thinking of objects in space exclusively in terms of their relationship to the child’s own body position. Objective frame of reference – thinking of objects in space relative to the position of objects or persons other than oneself. Shift from egocentric to objective – by 12 months Individual Differences in Ability Measured in mental tests for infants and toddlers – Bayley Scales of Infant Development ▪ designed for 2- to 42-month-olds, consists of cognitive, language, socio-emotional, adaptive behaviour, and motor tasks ▪ E.g. Attending to visual and auditory stimuli, following directions, looking for a fallen toy, and imitating (e.g. turning head to sound, matching colours) ▪ E.g. motor control, coordination, and ability to manipulate objects (e.g. making towers with blocks, kicking a ball) – Does not validly assess cultural and socioeconomic differences; particularly with Indigenous children Infant intelligence tests emphasize sensorimotor skills – do not predict adult intelligence – test for expected milestones Cortisol levels Language Development First birthday, first words Second birthday, a few hundred words Learning theorists – Imitation – Reward Modern theorists – Cognitive perspective – Mastering many distinct skills Perceiving Speech Phonemes: unique sounds joined to create words. Young infants can hear a wide range of phonemes but older infants can only hear those used in their native language. Study: pacifier connected to a recorder and loudspeaker – 1-month-olds: Link their sucking & “p” sound – Suck rapidly, but then get habituated – Tape is changed to a “b” sound – Start to suck rapidly again Around 1 year: Children become “tuned” to the language to which they are exposed in infancy. Pay more attention to familiar words. Infant-directed speech: speaking slowly in exaggerated changes of pitch and loudness when communicating with babies; formerly called “motherese.” First Steps to Speaking 2 months – cooing – long strings of vowel sounds produced by babies around 2 months of age (e.g., ooooooo or ahhhhhh) 5 or 6 months – babbling – speech-like sound that has no meaning (e.g., dah or bah, later combine different sounds, dah-mah-bah) 7 or 8 months – babbling includes intonation – Intonation: a pattern of rising or falling pitch similar to the pattern in normal conversation. Deaf children “babble” in sign language. – Make signs that match the tempo and duration of meaningful signing. Children with neurodevelopmental disabilities – delay. First Words “Mama” “dada” Infants understand that words are symbols, not just sounds Symbols represent actions and objects. Gestures: Symbols that children start to use around the time they begin to talk. – smack their lips to indicate hunger or wave “bye-bye” when leaving Use of gestures begins around first Birthday Fast Mapping Meaning to Words Naming explosion: around 18 months of age. – A period of language learning when children rapidly acquire new words. Fast mapping: meanings onto words using rules/strategies Learning Object Names – Joint attention – Parents encourage word learning by carefully watching what interests their children, and label it for them. Naming Errors Underextension: word is defined narrowly – Using “car” to refer only to the family car Overextension: word is defined too broadly – More frequently when children are producing words than when they are comprehending words – Say “doggie” to refer to a goat – “If you can’t remember the name for an object, say the name of a related object.” Styles of Learning Language Words that name objects, persons, or actions vs. Social phrases Referential style – intellectual tool Expressive style – social tool – social phrases: ▪ “Go away,” “What’s that?” and “I want it.” Basic Emotions: Happiness Social smiles at 2 months – Linked to physical and emotional states Laughter is added at 4 months – Often due to parental clowning behaviour Basic Emotions: Negative 4-6 months: Anger ‒ Goal-directed behaviour unmet 6 months: Fear – Stranger anxiety (stranger wariness) at 6 months Complex Emotions Guilt, embarrassment, and pride – Emerges at 18-24 months – Dependent upon cognitive development – Reflexive understanding of the self Recognizing and Using Others’ Emotions 6-7 months recognizes different emotions Infants often match their own emotions to other’s emotions – Difficulty matching the correct emotion to the correct situation (especially with negative emotions) Social referencing: looking to trusted person for emotional cues – If previously ignored by caregiver, will look to others Recognizing and Using Others’ Emotions 6-7 months recognizes different emotions Infants often match their own emotions to other’s emotions – Difficulty matching the correct emotion to the correct situation (especially with negative emotions) Social referencing: looking to trusted person for emotional cues – If previously ignored by caregiver, will look to others The Growth of Attachment Attachment: an enduring social-emotional relationship – Infant behaviour elicits caregiving from adults – Relies on infant’s perceptual and cognitive skills – 6 or 7 months, single attachment figure, the primary caregiver Internal working model: – Set of expectations about caregiver’s availability and quality of responsiveness Other Outcomes of Insecure Attachments Reactive attachment disorder: – Inappropriate interpersonal behaviours in children due to disruptions in the formation of attachment to the primary caregiver in early life Privation: – Condition in which basic necessities and comforts of life are not adequately provided Onset of Peer Interactions Begins around 6 months with nonsocial play. Around 12 months, children play side by side in parallel play. Around 15-18 months, youngsters engage in simple social play. Around 24 months, children begin cooperative play which includes imaginary play scripts Origins of Self-Recognition and Self-Concept Self-concept: attitudes, behaviours, and values that a person believes make the self unique. When do children know they exist? – Mirror-task – Preference for photos of self – Use of pronouns such as “I” or “me” What is Temperament? (1 of 3) Temperament: – Seen in first few weeks of birth and remains important – Consistent mood or styles of behaviour – Different dimensions New York Longitudinal Study (Thomas & Chess, 1956) – Traced the lives of 141 individuals from infancy to adulthood – Easy, difficult, slow-to-warm-up Three primary dimensions (Buss & Plomin, 1975, 1984): – Emotionality: Strength of emotional response – Activity: Tempo and vigor of child’s movements – Sociability: Extent person prefers to be with others Hereditary and Environmental Contributions to Temperament Twin studies show genetic influence on temperament Influence of hormones Influence of parenting styles (environment) Culture influences temperament patterns Stability of Temperament Temperament is modestly stable: – An active fetus may determine a difficult, unadaptive infant – Newborns who cry under moderate stress cry as 5-month-olds when moderately stressed Temperament and Other Aspects of Development (1 of 2) Temperament is linked to school success, peer interactions, and compliance with parents. – Persistent children – Shy, inhibited children – Anxious, fearful children – Extraverted, uninhibited toddlers Temperament is also related to helping others. – Young et al. (1999): Inhibition and helping in 2-year-olds study