History, Theory, and Research Strategies

History, Theory, and Research Strategies

Chapter 1History, Theory, and Research StrategiesWhat is Developmental Science?Developmental science field of study devoted to understanding constancy and change throughout the lifespanGreat diversity exists among investigators who study development, but all have 1 major goalMajor goal: to identify those factors that influence consistencies and transformations in people from conception to death

The Field of Human Development isScientific conduct empirical research Applied meaning practical use Interdisciplinary meaning that people from many different fields contribute to the study of human development

Theories of DevelopmentTheory orderly, integrated set of statements that describes, explains, and predicts behaviorExample: theory of infant-caregiver attachment would:1) describe the behaviors of babies 6-8 months old as they seek the affection and comfort of a familiar adult2) explain how and why infants develop this strong desire to bond with a caregiver3) predict the consequences of this emotional bond for future relationships Theories are important for 2 reasons:Provide organizing frameworks for our observationsTheories verified by research provide a sound basis for how to improve welfare of individuals3 Basic Issues in DevelopmentContinuous or discontinuous?One course of development or many?Nature or nurture?

Continuous or Discontinuous?Continuous a process of gradually augmenting the same types of skills that were there to begin withDiscontinuous a process in which new ways of understanding and responding to the world emerge a specific timesStages qualitative changes in thinking, feeling, and behaving that characterize specific periods of development

Is there one course of development or many?Stage theorists assume that people everywhere follow the same sequence of developmentBut field of human development is becoming increasingly aware that different contexts matterContexts unique combinations of personal and environmental circumstances that can result in different paths of changeExample:Personal: a shy person who fears social encounters develops in very different contexts from people who are more outgoing and readily seek out other peopleEnvironmental: people who grow up in a third world village society have different experiences in their families than people who grow up in an American cityRelative Influence of Nature and NurtureAre genetic or environmental factors more important?Nature inborn biological givensThe information we inherit from our parents at the moment of conceptionNurture the complex forces of the physical and social world that influence our biological makeup and psychological experiences before and after birthExample: do children learn language rapidly because they are genetically predisposed to do so or because their parents teach them from an early age?Relative Influence of Nature and Nurture (cont.)A theorys position on the roles of nature vs. nurture affect how it explains individual differencesNature/heredityStability that individuals who are high or low in a characteristic (i.e., verbal ability or anxiety) will stay that way throughout their lifeNurture/environmentPlasticity that change is possible and even likely if new experiences support it Development as a Dynamic SystemMore and more, researchers are regarding development as a dynamic systemPerpetually ongoing processConception to Death3 Influences on developmentBiologicalPsychologicalSocial

The Lifespan PerspectiveLeading dynamic systems approach4 major assumptions: development isLifelongMultidimensional and multidirectionalHighly plasticAffected my multiple, interacting forcesWithin each age period change occurs in 3 broad domainsPhysicalCognitiveEmotional/social

Lifespan View of Development

Periods of DevelopmentPrenatalConception to birthInfancy and ToddlerhoodBirth to 2 yearsEarly Childhood2 to 6 yearsMiddle Childhood6 to 11 yearsAdolescence11 to 18 yearsEarly Adulthood18 to 40 yearsMiddle Adulthood40 to 65 yearsLate Adulthood65 years to deathLifespan Assumption 1Development is Lifelong Every age period can have equally powerful effects on future changeNo single period has a supreme impact on the life course

Lifespan Assumption 2Development is Multidimensional and multidirectionalMultidimensional: development is affected by a blend of biological, psychological, and social forces Multidirectional in 2 waysdevelopment is not limited to improved performance. Every period consists of growth and declineChange is also multidirectional within each domain of development (physical, cognitive, and emotional/social)

Lifespan Assumption 3Development is Plastic or Flexible Adaptations and changes can occur at all agesAging is not an eventual shipwreckDifferent opportunities can yield different outcomes

Lifespan Assumption 4Development is influenced by multiple, interacting forcesBiological, historical, social, and culturalThese multiple influences work togetherCombine in unique ways in each individual life course

3 Types of InfluencesAge-graded influences events that are strongly related to age and therefore are fairly predictable in when they occur and how long they lastExample: most people begin walking shortly after their 1st birthdayHistory-graded influences influences on development unique to a particular historical era (ex. epidemics, wars, periods of economic prosperity or depression)Example: my great-grandmother was raised during a time of great economic depression and because of this she stockpiled goods in her home. Today she would be described in modern terms as a hoarderNonnormative influences irregular events that only happen to one person or a few people and do not follow a predictable timetableExample: an inspiring childhood teacher or meeting your life-partner on a random blind-dateScientific BeginningsScientific study of human development dates back to the late 19th and early 20th centuriesCharles Darwin 19th century theory of evolutionStudying natural selection and survival of the fittest lead other scientists to speculate about the evolution and development of humansThus, the scientific study of human development was born no pun intendedThe Normative PeriodG. Stanley Hall early 20th century - founder of the child study movementIntensive efforts to describe all aspects of development launched the normative approachNormative approach measures of behavior are taken on large numbers of individuals, and age-related averages are computed to represent typical development

Mid-20th Century TheoriesMid-20th Century study of human development expanded into a legitimate discipline and several theories and perspectives emergedThe psychoanalytic perspectiveBehaviorism and social learning theoryPiagets cognitive-developmental theory

The Psychoanalytic Perspective 1930s and 1940s driven by attempts to treat psychological problems: How and why do people become the way they are?Psychoanalytic perspective answer: people move through a series of stages in which they confront conflicts between biological drives and social expectations.How these conflicts are resolved determines the persons ability to learn, to get along with others, and to cope with anxiety2 main theorists Sigmund Freud psychosexual theoryErik Erikson psychosocial theory Psychoanalytic Perspective: FreudPsychosexual theory emphasizes that how parents manage their childs sexual and aggressive drives in the 1st few years of life is crucial for healthy personality development

IdLargest portion of the mindUnconscious, present at birthSource of biological needs & desiresEgoConscious, rational part of mindEmerges in early infancyRedirects id impulses acceptablySuperegoThe conscienceDevelops from ages 3 to 6 from interactions with caregiversPsychoanalytic Perspective: FreudPsychosexual stages During childhood sexual impulses shift their focus from the oral to the anal to the genital regions of the bodyIf parents strike an appropriate balance, then the child will grow into a well-adjusted adult

Psychosexual StagePeriod of DevelopmentOralBirth 1 yearAnal1 3 yearsPhallic3 6 yearsLatency6 11 yearsGenitalAdolescence Psychoanalytic Perspective: EriksonPsychosocial theory emphasized that the ego makes a positive contribution to development, acquiring attitudes and skills at each stage that make the individual an active, contributing member of society Basic psychological conflict between positive and negative occurs at each stage in developmentHow the conflict between positive and negative is resolved at each stage determines if healthy or maladaptive outcomes occurPsychoanalytic Perspective: EriksonPsychosocial StagePeriod of DevelopmentBasic trust v. mistrustBirth to 1 yearAutonomy v. shame and doubt13 yearsInitiative v. guilt36 yearsIndustry v. inferiority611 yearsIdentity v. role confusionAdolescenceIntimacy v. isolationEarly adulthoodGenerativity v. stagnationMiddle adulthoodEgo integrity v. despairLate adulthoodPsychoanalytic Perspective: Erikson1st 5 stages parallel Freud, but Erikson added 3 more adult stages Normal development must be understood in relation to each cultures life situationChild rearing can be understood only in relation to the competencies valued and needed by an individuals society Psychoanalytic Perspective: Strengths and weaknesses StrengthsEmphasis on the individuals unique life history Inspired research on many aspects of emotional and social development (infant-caregiver attachment, aggression, sibling relationships, child-rearing practices, morality, gender roles, and adolescent identity)WeaknessesNo longer in the mainstream of human development researchToo focused on the clinical approach, failed to consider other methodsPsychosexual stages and ego functioning are so vague that they are difficult or impossible to test empirically Behaviorism & Social Learning TheoryBehaviorism only directly observable events are appropriate to studyCompletely disregards anything that cant be directly observed (like Freuds id, ego, and superego)John Watson founder of behaviorism, backlash against psychoanalysisGoal: to create an objective science of psychology, disregard unseen inner workings of the mind

Behaviorism & Social Learning TheoryClassical conditioning Showed that a reflex (an involuntary reaction) could be caused to occur in response to a formerly unrelated stimulusDog Study:

Behaviorism & Social Learning TheoryWatson wanted to see if classical conditioning could be applied to childrens behavior Little Albert studyConditioned a baby to fear a white rat by paring it with a loud noisehttp://www.youtube.com/watch?v=FMnhyGozLyEConcluded that environment is the supreme force in developmentAdults can mold childrens behavior by controlling stimulus-response associationsViewed development as a continuous process, consisting of gradual increase with age in the number and strength of these associations Behaviorism & Social Learning TheoryOperant conditioning theory (B.F. Skinner)The frequency of a behavior can be increased or decreasedIncreased: follow the behavior with a reward called a reinforcer (food, praise, friendly smile)Decreased: follow the behavior with punishment (disapproval or withdrawal of privileges)Behaviorism & Social Learning TheoryAlbert Bandura most influential social learning theorist Social learning theory emphasizes modeling, AKA imitation or observational learning, as a powerful source of development Example: baby claps her hands after seeing her mother do soDiverse factors effect childrens motivation to imitateTheir own history of reinforcement or punishment for the behaviorThe promise of future reinforcement or punishmentEven vicarious reinforcement or punishment (observing the model being reinforced or punished)Today, social learning theory stresses the importance of cognition, or thinking Behaviorism & Social Learning Theory: Strengths and WeaknessesStrengthsBehavior modification - procedures that combine conditioning and modeling to eliminate undesirable behaviors and increase desirable responses Example: eliminating bad habits such as smoking and nail biting WeaknessesMany theorists believe behaviorism and social learning theory have too narrow of a focus on environmental influencesCriticized for underestimating peoples contributions to their own development Piagets Cognitive-Developmental TheoryJean Piaget most influential researcher on child development Did not believe that childrens learning depends on reinforcers Cognitive-developmental theory children actively construct knowledge as they manipulate and explore their world Based on biological concept of adaptationJust as structures of the body are adapted to fit with the environment, structures of the mind also develop to better fit with, or represent, the external worldPiagets Cognitive-Developmental TheoryInfancy & early childhood: childrens understanding is different from adultsExample: young babies do not realize that an object hidden from view (like a favorite toy) continues to exist Preschool: thinking is full of faulty logicExample: children younger than 7 years commonly say that the amount of a liquid changes when it is poured into a different-shaped containerEventually revise incorrect ideas via ongoing efforts to achieve equilibrium, or balance, between internal structures and information they encounter in their everyday worldsPiagets Cognitive-Developmental Theory4 broad stages occur as the brain develops and experiences expandSensorimotor stage (birth-2 years) cognitive development begins with the babys use of the senses and movements to explore the worldPreoperational stage (2-7 years) action patterns evolve into symbolic but illogical thinking Concrete operational stage (7-11 years) cognition is transformed into more organized, logical reasoning Formal operational stage (11 years-on) thought becomes an abstract, systematic reasoning systemPiagets Cognitive-Developmental Theory: Strengths and WeaknessesStrengthsChildren are active learners whose minds consist of rich structures of knowledgeStages sparked research on childrens conceptions of themselves, other people, and human relationshipsEncouraged development of discovery learning programs which emphasize direct contact with the environment WeaknessesUnderestimated the competence of infants and preschoolersStages pay insufficient attention to social and cultural influences on developmentCognitive changes do not stop occurring in adolescence Recent Theoretical Perspectives: Information Processing Information processing views the human mind as a computerA symbol-manipulating system through which information flowsInformation is presented to the senses during input, information is actively coded, transformed, and organized, then emerges as output, a behavioral responseRegard people as actively making sense of their own thinkingContinuous change thought processes are regarded as similar at all ages but present to a lesser or greater extent Uses flowcharts to map the precise steps individuals use to solve problems and complete tasks Example: 5-year-old solving a bridge building problemUse the blocks to build a bridge a cross a river painted on the floor too wide for any single block to spanChild discovers how to counterweight and balance the bridge

Recent Theoretical Perspectives: Information Processing StrengthsCommitment to rigorous research methods Provided precise accounts of how people tackle many cognitive tasks WeaknessesBetter at analyzing thinking into components than putting them back together into a comprehensive theory Virtually ignores aspects of cognition that are not linear and logicalSuch as imagination and creativity Recent Theoretical Perspectives: Developmental Cognitive NeuroscienceDevelopmental cognitive neuroscience studies the relationship between changes in the brain and cognitive processing and behavior patternsUses brain-imaging techniques to analyze relationships between brain functioning, cognitive capacities, and behaviorGain knowledge regarding:The types of experiences that support or undermine brain development at various agesThe brain bases of many learning and behavior disorders Example: ADHD has been linked to dysfunction in brain regions such as the prefrontal cortex

Recent Theoretical Perspectives: EthologyEthology concerned with the adaptive, or survival, value of behavior and its evolutionary history Critical period a limited time span during which the individual is biologically prepared to acquire certain adaptive behaviors but needs the support of an appropriately stimulating environmentExample: if children are deprived of adequate food or physical and social stimulation during their early years, will intelligence be impaired?

Recent Theoretical Perspectives: EthologySensitive period time that is optimal for certain capacities to emerge and in which the individual is especially responsive to environmental influenceBoundaries are less well-defined than those of the critical periodDevelopment can occur later, but it is harder to induce

Recent Theoretical Perspectives: Evolutionary Developmental PsychologyEvolutionary developmental psychology seeks to understand the adaptive value of specieswide cognitive, emotional, and social competencies as those competencies change with age Clarify origins and development of behaviors Example: life-threatening risk taking in adolescents and male-to-male violence may have been adaptive in our ancestors But today, our lifestyles are so radically different that these behaviors are no longer adaptive Recent Theoretical Perspectives: Vygotskys Sociocultural TheorySociocultural theory focuses on how culture is transmitted on to the next generationvalues, beliefs, customs, and skills of a social groupSocial interaction necessary for children to acquire the ways of thinking and behaving that make up a communitys culture Views cognitive development as a socially mediated processChildren depend on assistance from adults and more expert peers to tackle new challenges Recent Theoretical Perspectives: Ecological Systems Theory Ecological systems theory views the person as developing within a complex system of relationships affected by multiple levels of the surrounding environment Views the environment as a series of nested structuresMicrosystem innermost level, activities and interaction patterns in immediate surroundings (immediate family, school)Mesosystem second level, connections between microsystemsExosystem third level, social settings that do not contain the person but affect experiences in immediate settings (neighbors, extended family, board of directors in the workplace)Macrosystem outermost level, cultural values, laws, customs, and resources

Studying DevelopmentHypothesis prediction about behavior drawn from a theoryResearch methodsBasic approach to gathering informationSystematic observations, self-reports, clinical or case studies, ethnographiesResearch designsOverall plans for research studies Permit the best possible test of the investigators hypothesisCommon Research Methods: Systematic ObservationNaturalistic observationIn the field or natural environment where behavior happensExample: observing children in their homes or schoolsStructured observationLaboratory situation set up to evoke the desired behaviorAll participants have an equal chance to display behaviorUsed when the behavior of interest is very difficult or impossible to observe in the field

Common Research Methods: Self-ReportsClinical interviewResearchers use a flexible, conversation styleProbe for the participants point of view

Structured interviewEach participant is asked the same questions in the same way Can use questionnaires to assess large numbers of people

Common Research Methods: Clinical, or Case Study Brings together a wide range on information on one personInterviews, observations, test scores, etc. Well-suited to study types of individuals who are few in number but vary widely in characteristics Example: prodigies extremely gifted children who attain adult competence in a field before age 10

Common Research Methods: EthnographyDescriptive, qualitative techniqueGoal: understand a culture or a distinct social groupParticipant observation researcher spends months, and sometimes years, in the cultural community, participating in its daily life

General Research Designs: CorrelationalReveals relationships between variables (between characteristics and behavior or development)Does NOT reveal cause-effect!!!Correlation coefficient number that determines strength and direction of relationshipStrengthSize of the number between 1 and -1The closer to 1 (positive or negative) the stronger the relationshipDirection Positive: as one variable increases/decreases so does the otherNegative: as one variable increases the other decreases

General Research Designs: ExperimentalCan determine cause-effect relationships because researchers randomly assign participants to two or more treatment conditionsIndependent variablesWhat the researcher expects to cause changes in another variableDirectly manipulated/controlled by the researcherDependent variablesWhat the investigator expects to be influenced by the independent variableResearcher measures but does not manipulate General Research Designs: ExperimentalRandom Assignment - unbiased procedure used to assign participants to treatment conditionsIncreases chances that characteristics will be equally distributed across conditions

General Research Designs: Modified ExperimentsField ExperimentCapitalize on opportunities for random assignment in natural settingsNatural/Quasi-experiment Compare treatment conditions that already existExample: gender, ageTry to match groups as closely as possible Developmental Research DesignsLongitudinalSame group studied at different timesCross-SectionalDiffering groups studied at the same timeSequentialSeveral similar cross-sectional or longitudinal studies at varying timesDevelopmental Research Designs: Longitudinal StrengthsTracks performance of each person over time, can identify common patterns and individual differences in developmentCan examine relationships between early and later events and behaviors WeaknessesParticipants may drop out of the study or move awayPractice effects performance may improve as a result of better test-taking skills and increased familiarity with the test, not because of factors associated with developmentCohort effects results based on one cohort may not apply to people developing at different timesBecause people born in the same time period are influenced by historical and cultural conditions of that specific timeEthics in Lifespan ResearchInstitutional Review Boards (IRB)Committees that weigh the costs of the research to participants in terms of inconvenience and possible psychological or physical injury against the studys value for advancing knowledge and improving conditions of life If there are risks to participants safety and welfare that the research does not justify, preference is always given to the participants interests Rights of Research ParticipantsProtection from harmInformed consentPrivacy Knowledge of resultsBeneficial treatments See Table 1.8 page 39, in text book