PSY 103 - Developmental Psychology
Stages of prenatal development - fetus
- 30 weeks (9th to 38th) - growth and finishing
Bronfenbrenner's Bioecological Theory
- 5 levels of environmental influence: individual, microsystem, mesosystem, exosystem, macrosystem
Stages of prenatal development - embryo
- 6 weeks (3rd to 8th) - arms, legs, face, organs, muscles all develop - heart begins beating
APGAR Scale
- Appearance - Pulse - Grimace - Activity - Respiration
Stages in Erikson's theory of psychosocial development
- Basic trust v. mistrust (birth-1) - Autonomy v. shame/doubt (1-3) - Initiative v. guilt (3-6) - Industry v. inferiority (6-11) - Identity v. role confusion (adolescence) - Intimacy v. isolation (early adulthood) - Generativity v. stagnation (middle adulthood) - Ego integrity v. despair (late adulthood)
Theoretical perspectives in developmental psychology - Learning
- Behaviorism (conditioning) - Social learning (social cognitive theory)
Theoretical perspectives in developmental psychology - Contextual
- Bronfenbrenner: bioecological theory
Evolutionary Psychology
- Darwin's principles of natural selection and survival of the fittest applied to individual behavior
Two phases of human development
- Early phase: childhood and adolescence - Later phase: young adulthood, middle age, old age
Theoretical perspectives in developmental psychology - Evolutionary/Sociobiological
- Evolutionary psychology - Ethology
Theoretical perspectives in developmental psychology - Psychoanalytic
- Freud: psychosexual development - Erikson: psychosocial development
Psychometric approach
- IQ tests - Developmental tests (cognitive, language, motor, social-emotional, adaptive behavior)
Piaget - Sensorimotor Stage
- Imitation - Object permanence - Representational thinking - Symbolic development - Categorization - Causality - Number
Theoretical perspectives in developmental psychology - Cognitive
- Piaget: Cognitive stage theory - Vygotsky: Sociocultural theory - Information processing theories - Neo-Piagetian theories
Periods of Lifespan
- Prenatal (conception-birth) - Infancy/toddlehood (birth-age 3) - Early childhood (3-6) - Middle childhood (6-11) - Adolescence (11-20) - Emerging & young adulthood (20-40) - Middle adulthood (40-65) - Late adulthood (65+)
Piagetian Approach
- Sensorimotor Stage - Preoperational Stage - Concrete operational stage - Formal operational stage
Size and appearance of newborn
- average neonate is 20 inches long, 7.5 pounds - fontanels: soft plates of head - lanugo: fuzzy prenatal hair - vernix caseosa: oily protection against infection
Newborn reflexes - moro
- baby is dropped or hears loud noise -- embracing motion by arching back, extending legs, arms and fingers
Newborn reflexes - tonic neck
- baby is laid down on back -- fencer position
Newborn sense of taste and smell
- begins to develop in womb - prefer sweet tastes at birth - quickly learn to like new tastes - have odor preferences from birth - can locate odors and identify mother by smell from birth
Forces of development
- biological - psychological - sociocultural - life-cycle
Context of development
- biology: heredity, maturation - culture: family, socioeconomic status & neighborhood, culture, race & ethnicity
Preterm Babies
- born weeks before their due date - may be appropriate weight for length of pregnancy
Newborn reflexes - babkin
- both palms are stroked at once -- mouth opens, eyes close, neck flexes, head tilts foward
Brain development
- brain is most developed organ at birth - factors associated with brain growth and development during first 2 years: neurogenesis, growth of support cells (glial cells), increase in dendritic/axonal branching, loss of neurons and synaptical connections, increase in production of neurotransmitter
Age-related changes in body proportions
- cephalocaudal trend (head to tail): organized pattern of physical growth and motor development; during the prenantal period, head and chest develop more rapidly than the lower part of the body - proximodistal trend (near to far): pattern of physical growth and motor control that proceeds from the center of the body outward; during infancy and childhood, arms and legs grow ahead of the hands and feet
Newborn reflexes - rooting
- cheek or lower lip is stroked -- head turns, mouth opens, sucking begins
Piaget's Cognitive Development Theory
- children actively construct knowledge as they manipulate and explore their world - they build schemas by the process of assimilation and accommodation - 4 stages: sensorimotor, pre-pperational, concrete operational, formal operational
Vygotsky's Sociocultural Theory
- children's cognitive processes are guided by social and cultural processes - social interactions are important for cognitive growth - zone of proximal development: gap between what a child can do alone v. with help - scaffolding: temporarily support a child to master a task
Designs in developmental research - sequential
- combining cross-section and longitudinal designs
Influences on early physical growth - benefits of breastfeeding
- correct fat-protein balance for humans - nutritionally complete (no other food until 6 months) - more easily digestible (due to different bacteria) - faster growth - disease protection (transfer of antibodies) - better jaw and tooth development - easier transition to solid food
Correlational v. Experimental Designs
- correlational approach: permits study of issues that cannot be studied experimentally; can be used to examine data from the real world (increasing external validity); examines variables that cannot be easily manipulated - much developmental work is correlational work or quasi-experimental work (comparing age groups)
Data Collection Methods - Quantitative methods
- counting - judging/rating (features of persons or situations) - Testing (IQ) - Questionnaire (personality, attitude) - Observation (behavior) - Psycho-physiological measurements
Controversies in developmental psychology - Continuity-Discontinuity
- development is a smooth progression over time or series of abrupt shifts?
Effects in developmental research - Cohort effects
- differences caused by experiences and circumstances unique to the generation to which one belongs - normative, history-graded influences
Effects in developmental research - time of measurement effects
- differences stemming from sociocultural, environmental, historical, or other events at the time the data are obtained from the participants
Twins
- dizygotic twins (fraternal): two ova, two sperm; share 50% of genes; most common type of multiple birth - monozygotic twins (identical): one ovum, one sperm; one zygote divides into two individuals; share 100% of genes; about 1 in every 285 births
Dominant-Recessive Inheritance
- dominant inheritance: dominant allele affects the child's characteristics (e.g. hair color); recessive allele has no effect - recessive inheritance: two identical alleles are inherited -- expression of nondominant trait
Chromosomal abnormalities
- errors in cell division - can occur in autosomes or sex chromosomes - result in missing or extra chromosomes - leading cause of infant death in USA
Teratogens
- external agents that can pass through the placenta and negatively affect the developing embryo or fetus - factors affecting harm from teratogens: dose, heredity, age at time of exposure
Measuring heritability
- family studies: the degree to which bio-relatives share traits - adoption studies: the degree to which adopted children resemble biological relatives or adopted family members - twin studies: concordance (the degree to which MZ and DZ twins resemble each other for a trait); a concordance rate of 100% indicate a fully genetically determined trait
Newborn sense of touch
- first sense to develop - sensitive to touch on mouth, palms, soles, genitals - highly sensitive to pain (relieve pain with sugar solution, gentle holding; physical touch released endorphins)
Evolutionary Psychology - evolutionary development psychology
- focus on adaptive value of human competencies and their development with age; which behaviors are adaptive at different ages?
Research Methods - Experimental
- focus: causality - is X a cause of Y?
Research Methods - Observational
- focus: description - what is the nature of phenomenon X?
Research Methods - Correlational
- focus: prediction - from knowing X, can we predict Y?
Newborn reflexes - babinski
- foot is stroked -- toes fan out; foot twists out
Genotypes and Phenotypes
- foundations of development are heredity and environment - heredity supplies each individual's genotype while heredity AND environment combine to create the phenotype - genotype: genetic make-up of an individual/organism - phenotype: observable characteristics of an individual/organism; product of genotype
Newborn sense of hearing
- functional before birth - can hear a wide variety of sounds at birth - prefer complex sounds to pure tones - learn sound patterns within days - sensitive to voice and biologically prepared to learn language
Variation in the phenotype is a function of
- genotype - shared environment (family, school) - non-shared environment (unique experiences) - gene-environment interactions - gene-environment correlations - error
Stages of prenatal development - zygote
- germinal stage - 2 weeks - fertilization, implantation, start of placenta
Motor development: sequence and trends
- gross motor development (crawling, standing, walking) - fine motor development (reaching and grasping) - sequence is fairly uniform, though individual rate of motor progress differs
Information Processing Approach
- habituation: a type of learning in which familiarity is indicated by reduced response - dishabituation: increase in responsiveness after presentation with a new stimulus
Genetic counseling
- helps prospective parents asses risk of bearing a child with a genetic defect - karyotype chart shows chromosomal abnormalities - especially helpful when already have biological children with defect, family history, ethnicity
Newborn reflexes - walking/stepping
- hold under arms with bare feet touching surface -- steplike motions that look like walking
Behavioral Genetics
- how does heredity and environment influence traits? - heritability: statistical estimate of the variance of interindividual differences explained by genetic factors
Evolutionary Psychology - developmental systems approach
- human development is a function of bidirectional interactions between person and environment
Even when carefully constructed, infant tests are poor predictors of later intelligence. Why?
- infant scores often do not reflect true abilities because young children are likely to become distracted, tired, bored - items on infant tests do not tap the same dimensions of intelligence measured at older ages - however, tests are good as a screening instrument helping to find extremely low-scoring babies
Data Collection Methods - Qualitative methods
- interview - observation - nonreactive procedures - used single case studies, document analysis, field research
Controversies in developmental psychology - Universal-Context Specific
- is there just one path of development? - what speaks for and against the notion of one path of development?
Behaviorism & Social Learning
- learning is a long-lasting change in behavior based on experience - respond base on whether situation is painful/threatening or pleasurable - types of learning: classical conditioning (Pavlov/Watson; stimulus-response); operant conditioning (Skinner; reinforce/punishment); Social learning (Bandura; modeling)s
Newborn sense of vision
- least developed sense at birth (there is not a lot of visual input during pregnancy, visual structures in eyes and brain not fully formed yet) - limited acuity - san environment, track moving objects - color vision improves in first two months
Low Birth Weights
- maternal risk factors: under-age or over-age; low SES; poor nutrition; smoking and drinking; high blood pressure; stress
Influences on Early Language Development
- maturation of the brain - social interaction with parents and caregivers (prelinguistic period + vocabulary development + bilingual code mixing)
Small-for-Date Babies
- may be born at due date or preterm - below expected weight for length of pregnancy
Key propositions of lifespan psychology
- multidimensionality (change in different domains, different types of change...) - multidirectionality (dynamic of gains and losses) - plasticity and reserve capacity - changes in resource allocation - integration in historical (and cultural) context - changes in the relative influences of biology and culture
Controversies in developmental psychology - Nature-Nurture
- nature: biological influences, inborn, based on genetic inheritance - nurture: environmental influences, including the physical, social, and cultural world
Erikson: Psychosocial theory
- neo-Freudian - influence of society - development is lifelong - 8 stages: each involves a crisis that can be resolved positively and negatively
Behaviorist Approach - classical conditioning
- neutral stimulus is paired with a stimulus that leads to a response
Low Birth Weights
- newborns weighing less than 5.5 lbs (15.5% of all births, most in developing countries) - greater risk for the following long-term effects: neurological and cognitive impairments, lower academic achievements, social, behavioral and attention problems
Influences on early physical growth - examples
- nutrition - malnutrition - emotional well-being
The objectives of lifespan psychology are to...
- offer an organized account of the overall structure and sequence of development across the lifespan - identify the interconnections between earlier and later developmental events and processes - delineate the factors and mechanisms which are the foundation of lifespan development - specify the biological and environmental opportunities and constraints which shape lifespan development of individuals - determine the range of possible and optimal development of individuals
Early approaches to developmental psychology - "On the Perfectability and Development of Man" (Tetens)
- on the predictability of the human psyche (Seelennature) and its development in general - on the development of the human body - on the analogy between the development of the psyche (mind) and the development of the body - on the differences between men (huamsn) in their development - on the limits of development and the decline of psychological abilities - on the progressive development of the human species - on the relationship between optimization of man and his life contentment
Embryonic Period (3rd to 8th week)
- outer layer (formation of amnion, chorion, placenta) - organogensis (development of organ systems); related to critical periods, time of most rapid development and greatest environmental influence - inner layer cells differentiate into distinct structures (endoderm-gut, lungs; mesoderm-bone, muscles, circulatory system, heart; ectoderm-brain, spinal cord, skin)
Newborn reflexes - darwinian
- palm is stroked -- makes strong fist
Information Processing Approach - Categorization
- perceptual: based on how things look; birds and planes both have wings and can fly - conceptual: based on what things are; chairs, tables, and sofas are all furniture items
Freud: Psychosexual theory
- personality forms through unconscious conflicts between biological drives and societal requirements - 5 stages: oral, anal, phallic, latency, genital
Domains of Development
- physical (body & brain growth, sensory functioning, motor skills, health) - cognitive (learning, attention, language, thinking, memory, creativity) - psychosocial (emotions, well-being, social relationships, personality)
Take-home message
- physical development is characterized by spurts (infants and toddlers grow in spurts; also develop motor skills partly in spurts) - one major aspect of brain development in childhood is synaptic pruning (unnecessary or inefficient connections are eliminated)
Physical development: body growth
- physical growth occurs rapidly during the first two years - height and weight gains occur in spurts - baby fat (peaks around 9 months) helps infants to keep a constant body temperature
Milestones of reaching and grasping
- prereaching: uncoordinated swings toward an object - reaching: with two hands (3 months), then one (7 months) - ulnar grasp (3 months): adjust grip to object, move objects from hand to hand - pincer grasp (1 year)
Death during Infancy
- primary causes worldwide: preterm delivery, sepsis or pneumonia, asphyxiation at birth - birth defects are leading cause in the US - improvements in the US infant mortality rates likely due to SIDS awareness
Behaviorist Approach - operant conditioning
- probability of behavior is influenced by stimulus following behavior
Newborn reflexes - swimming
- put into water face down -- well-coordinated swimming movements
Heredity & Environment: Working Together
- reaction range: potential variation in a trait - canalization: genetic restriction of development to one or a few potential outcomes; highly canalized traits require extreme environmental conditions to change their genetically set outcome; canalization promotes survival by ensuring that children will develop certain species-typical skills
Fetal Period (2nd month-birth)
- refinement of structures: rapid increase in size and efficiency of organ systems; organs become functional - age of viability: beginning of 7th month (about 24 weeks)
Piaget - Sensorimotor
- schemas (organized patterns of thought and behavior) become more organized - learning happens through sense and motor activity - learning through circular reactions = learning to produce desired events originally discovered by chance - at end of sensorimotor stage: representational ability
Genetic Foundations: Genes
- segments of DNA - two forms of each gene occur at the same place on the chromosome, one inherited from the mother and one from the father - each form is called an allele - homozygous: the two alleles are alike - heteozygous: the alleles differ
Sensitive periods in brain development
- stimulation is vital when brain is growing rapidly - experience-expected growth: ordinary experiences 'expected' by brain to grow normally - experience-dependent growth: additional growth as a result of specific learning experiences
Chromosomes
- store and transmit genetic information - each chromosome contains 1000s of genes - each cell contains 23 pairs of chromosomes (46) - autosomes: 22 pairs not related to sexual expression - sex chromosomes: 1 pair determining sex - gametes: sex cells (sperm, ovum) have only 23 chromosomes) - fusion of sex cells at conception creates zygote with 46 chromosomes (23 from mother, 23 from father)
Evolutionary/Sociobiological Perspective - Ethology
- studies the adaptive value of behavior and its evolutionary history - critical period: organism is biological prepared to acquire adaptive behaviors during a limited time span - sensitive period: an optimal time for certain capacities to emerge; a time in which the organism is especially responsive to environment
Evolutionary/Sociobiological Perspective - Developmental (cognitive) neuroscience
- studies the relationship between changes in the brain and the developing person's social, emotional, and cognitive, processing and behavior
Designs in developmental research - cross-sectional
- testing people of different ages at the same time
Cross-sectional design
- testing people of different ages at the same time - allows examining age differences but NOT age-related change - says nothing about the continuity of development - confoundation of age and cohort effects: differences between age groups (cohorts) may result from environmental events or developmental processes
Designs in developmental research - longitudinal
- testing the same people repeatedly at different time points
Psychometric Approach
- tests for the early home environment - early intervention programs
Longitudinal design
- the same individuals are tested repeatedly at different time points in their lives - allows examining: age-related changes (within individuals); differences in change across individuals; associations between rates of change - no cohort effects because only one cohort is studied - confoundation of age and time effects: changes could result from changes in underlying processes or factors related to the time of measurement - problematic: practice effects, participant dropout, limited generalizability, time consuming, expensive
Controversies in developmental psychology - Stability-Change
- to which degree do people remain the same over time? - what stays the same, what changes as we age?
Longitudinal-Sequential Design
- two or more longitudinal studies - age-related changes and cohort effects
Study of development has 2 aims...
- understand the origins (ontogeny) and development of behavior within an individual (intraindividual change) - understand age-related interindividual differences in behavior
Early Speech Characteristics
- understanding grammar precedes use of it - underextension of word meanings ("doggy" only refers to your dog) - overextension of word meanings (all men with grey hair are "Grampa") - overregularizing of rules ("I thinked about it!")
Information Processing Approach - Causality
- understanding that one event causes another - allows us to control and predict world - develops at around 6 months, manipulating a mobile with hands or feet
Reflexes
- unlearned and automatic response to a stimulus - controlled by lower brain centers (brain stem) - help infant adapt to environment and survive - provide building blocks for later skills - diagnostic of normal neurological development
Key Principles of Darwin's Theory of Evolution
- variation: living beings vary in all sots of ways - inheritance: some of these variations are passed down from parent to offspring - selection: organisms with traits suited to environment survive and pass these traits to their offspring; thus certain variations help with reproduction and survival and these organisms all have (slightly) more offspring
Information Processing Approach
- visual preference: tendency to look longer at one sight than another - novelty preference: paying more attention to new visual stimuli; demonstrating ability to tell new from old
Effects in developmental research - Age effects
- within-subject effects - differences caused by underlying processes, such as biological, psychological, or sociocultural changes - not caused by passage of time per se
Influences on development - Normative history-graded
events that most people in a specific culture experience at the same time (e.g. war, epidemics, specific attitudes, improvement in medical care)
Influences on development - Normative age-graded
experiences caused by biological, psychological and sociocultural forces that are highly correlated with chronological age (e.g. menopause, decline in speed of information processing, retirement)
Forces of development - Biological
genetic and health-related factors (e.g. menopause, changes in organ systems)
Forces of development - Psychological
internal perceptual, cognitive, emotional, personality factors (e.g. memory capacity, extraversion)
Forces of development - Sociocultural
interpersonal, societal, cultural, ethnic, factors (e.g. country, race)
Influences on development - nonnormative
random or rare events that may be important for specific individual but are not experienced by most people (e.g. accidents, move, winning in lottery)
Forces of development - Life-cycle
reflect differences in how the same event affects people at different points in their lives
Developmental Psychology
the study of age-related interindividual differences and age-related intraindividual change
Fertilization
union of sperm and ovum into one single-celled zygote
