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Lecture Notes for HDEV: Human Lifespan Development, 6th Edition

Lecture Notes for HDEV: Human Lifespan Development, 6th Edition summarizes important topics for quick revision.

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    1 Chapter 1 H i s t o r y , T h e o r i e s , a n d M e t h o d s Chapter Overview This chapter provides the general introduction to the field of developmental psychology . It begin s with a definition of child development and a discussion of the purposes and goals of theory and research in the field of developmental psychology . A brief survey of the pioneers in the field of developmental psych ology , including John Locke, Jean - Jacques Rousseau, G. Stanley Hall, Alfred Binet, William Perry, and Gisella Labouvie - Vief , is followed by a description and evaluation of each of the major perspectives on child development — psychoanalytic , learning ( behavioral and social cognitive theories ), cognitive , biological , ecological , and sociocultural . Next, the nature - nurture, continuity - discontinuity, and active – passive controversies in the field of development are overviewed. Finally, research methods are described ( natur al istic - observation, case study, correlation, experimental research, longitudinal research, cross - sectional studies, and cross - sequential research) , including a presentation of the general idea behind the scientific method, ways of gathering information in child developmental scienc e, the correlational method (and its limitations), and how to approach and design experiments. The chapter ends with a n overview of the special methods needed to assess development over time , specifically longitudinal versus cross - sectional research and the ways in which the cross - sequential research design handles the advantages and disadvantages of each , as well as a discussion of the ethical issues in research with children. Chapter Learning Objectives Having read the chapter, students should be able to achieve the objectives given below . • E xplain what child development is • D escribe why it is important to study child development • D iscuss the history of child development • C ompare the different developmental views across time • C ompare the different major theories of child development • A nalyze the major controversies in the study of child development • I dentify and c ompare different research methods used in the stud y of child development • E xplain the purpose o f each of the different research methods discussed in th is chapter • D escribe the different ethical considerations when conducting developmental research Chapter Outline

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    2 I. The Development of the Study of Human Development • Developmental psychology is the discipline that studies the physical, cognitive, social, and emotional development of humans . • In ancient times and in the Middle Ages, c hildren often were viewed as innately evil and discipline was harsh . • English p hilosopher John Locke (1632 - 1704) believed that the child came into the world as a tabula rasa — a “blank tablet” or clean slate — that was written on by experience . • J ean - Jacques Rousseau (1712 - 1778) , a Swiss - French philosopher, argue d that c hildren are inherently good and that, if allowed to express their natural impulses , they will develop into generous and moral individuals . • G. Stanley Hall (1844 - 1924) is credited with founding child development as an academic discipline and bringing scientific attention to focus on the period of adolescence. • French psychologist Alfred Binet (1857 - 1911), along with Theodore Simon (1872 - 1961), developed the first standardized intelligence test near the beginning of the 20 th century. • In the 20 th century, psychologists began to take on a life - span perspective , in which they viewed human development as occurring throughout the individual’s lifetime . o William Perry and Gisella Labouvie - Vief , for example, have stud ied the development of cognitive complexity from adolescen ce to late adult hood . o K. W. Schaie and others have studie d trends in various mental abilities throughout middle and late adulthood , showing that some abilities decline in middle and late adulthood, but others that represent the accumulation of decades of knowledge can advance into late adulthood . II. Theories of Development • John B. Watson (1878 - 1958) , the founder of American behaviorism , viewed development in terms of learning theory . o He generally agreed with John Locke that children’s ideas, preferences, and skills are shaped by experience . • Arnold Gesell expressed the opposing idea that biological maturation — the unfolding of genetically determined traits, structures, and functions — was the main principal of development . A. The Psychoanalytic Perspective • A number of theories fall within the psychoanalytic perspective . o Each owes its origin to Sigmund Freud and views children — and adults — as caught in conflict .

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    3 • The expression of basic drives, such as sex and aggression, conflict with parental expectations, social rules, moral codes, even laws . o But the external limits — parental demands and social rules — are brought inside or internalized . o Once internalization occurs, the conflict takes place between opposing inner forces . • Freud’s theory of psychosexual development and Erik Erickson’s theory of psychosocial development are stage theor ies that see children developing through distinct periods of life . o Each suggests that the child’s experiences during early stages affect the child’s emotional and social life at the time and later on . Sigmund Freud’s Theory of Psychosexual Development • Sigmund Freud ’s (1856 - 1939) theory of psychosexual development focused on the following three parts of the personality . o I d : It is present at birth and is unconscious . ▪ It represents biological drives and demands instant gratification, as suggested by a baby’s wailing. o E go : It curbs the appetites of the id and makes plans that are in keeping with social conventions so that a person can find gratification but avoid social disapproval . o S uperego : It develops throughout infancy and early childhood . ▪ It brings inward the wishes and morals of the child’s caregivers and other member s of the community . • According to Freud, the following are the five s tages of p sychosexual d evelopment . o Oral stage : During the first year of life, “oral” activities such as sucking and biting bring pleasure and gratification . o Anal stage : During this stage, g ratification is obtained through control and elimination of waste products . o Phallic stage : During this stage, p arent - child conflict may develop over masturbation , which many parents treat with punishment and threats . o Latency stage : By age five or six, Freud believed, children enter this stage during which sexual feelings remain unconscious , children turn to schoolwork , and they typically prefer playmates of their own sex . o Genital stage : The final stage of psychosexual development begins with the biological changes that usher in adolescence . ▪ Adolescents generally desire sexual gratification through intercourse with a member of the other sex .

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    4 Evaluation • Freud’s views about the anal stage have influenced child - care workers to recommend that toilet training not be started too early or handled punitively . o His emphasis on the emotional needs of children has influenced educators to be more sensitive to the possible emotional reasons behind a child’s misbehavior. • Freud’s work has also been criticized . o For one thing, Freud d eveloped his theory on the basis of contacts with adult patients (mostly women) (Henley, 201 9 ) , rather than observing children directly . o Some of Freud’s own disciples, including Erik Erikson , believe that Freud place d too much emphasis on basic instincts and unconscious motives . Erik Erikson’s Theory of Psychosocial Development • Erik Erikson (1902 - 1994) modified Freud’s theory and extended it through the adult years . o Erikson’s theory , like Freud’s , focuses on the development of the emotional life and psychological traits, but Erikson focuses on social relationships rather than sexual or aggressive instincts . o Therefore, Erikson speaks of psychosocial development rather than of psychosexual development . o Furthermore, Erikson p lace s greater emphasis on the ego, or the sense of self . • Erikson (1963) extended Freud’s five stages to eight to include the concerns of adulthood . o Rather than label his stages after parts of the body, Erikson labeled them after the life crisis — an internal conflict that attends each stage of psychosocial development — tha t people might encounter during that stage . • Early experiences affect future development s . o Successful resolution of each crisis bolsters children’s sense of identity — of who they are and what they stand for — and their future expectation of future success . • Erikson’s views , like Freud’s, have influenced child rearing, early childhood education, and child therapy . o For example, Erikson’s views about an adolescent identity crisis — a period of inner conflict during which one examines one’s values and makes decisions about one’s life roles — have entered the popular culture and have affected the way many parents and teachers deal with teenagers .

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    5 Evaluation • Erikson’s views are appealing in that they emphasize the importance of human consciousness and choice . o There is also s ome empirical support for the Eriksonian view that positive outcome s of early life crises help put people on the path to positive development (Gfellner & Cordoba , 201 7 ; Marcia, 2010) . B . The Learning Perspective: Behavioral and Social Cognitive Theories Behaviorism • John B. Watson argued that a scientific approach to development must focus on observable behavior only and not on things like thoughts, fantasies, and other mental images . • Classical conditioning is a simple form of learning in which an originally n eutral stimulus c omes to bring forth, or elicit, the response usually brought forth by a second stimulus as a result of being paired repeatedly with the second stimulus . • Behaviorists arg ue that much emotional learning is acquired through classical conditioning . • In operant conditioning , children learn to do something because of its effects . • B. F. Skinner introduced the key concept of reinforcement . o Reinfo rcers are stimuli that increase the frequency of the behavior they follow . • Skinner distinguished between positive and negative reinforcers . o Positive reinforcers i ncrease the frequency of behaviors when they are applied . F ood and approval usually serve as positive reinforcers . o Negative reinforcers i ncrease the frequency of behaviors when they are removed . F ear acts as a negative reinforcer in that its removal increases the frequency of the behaviors preceding it . • Extinction results from repeated performance of operant behavior without reinforcement . o Punishments are a versive events that suppress or decrease the frequency of the behavior they follow . • Operant conditioning is used every day in the socialization of young children . o Parents and peers influence children to acquire behavior patterns they consider to be appropriate to their gender through the elaborate use of rewards and punishments. o Boys may ignore other boys when they play with dolls and housekeeping toys , but play with boys when they use transportation toys. This type of conditioning is obviously restrictive and harmful when it counter s the child’s personal

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    6 desires. Social Cognitive Theory • Social cognitive theorists such as Albert Bandura (1986, 201 1 ) have shown th at much learning occurs by observing other people, reading, and viewing characters in the media . • Observational learning occurs when children observe how parents cook, clea n, or repair a broken appliance . • In social cognitive theory, the people after whom one pattern s one’s own behavior are termed models . Evaluation of Learning Theories • Learning theories allow people to e xplain, predict, and influence many aspects of behavior . • Many of the teaching approaches used in educational TV shows are based on learning theory . C. The Cognitive Perspective • Cognitive theorists focus on people’s mental processes . • One cognitive perspective is cognitive - developmental theory , advanced by Swiss biologist Jean Piaget (1896 - 1980) and further developed by many theorists. o This theory holds that the child’s abilities to mentally represent the world and solve problems unfold as a result of the interaction of experience and the matura tion of neurological structures. Cognitive - Developmental Theory • Through his studies, Piaget realized that when children answered questions incorrectly , their wrong answers still often reflected consistent — although illogical — mental processe s . • Piaget used the following concepts to describe and explain cognitive development . o S cheme s : It is a p attern of action or mental structure that is involved in acquiring or organizing knowledge . o A daptation : It is the interaction between the organism and the environment . It consists of assimilation and accommodation, which occur throughout life . o A ssimilation : It is the process by which someone responds to new object or event s according to existing schemes or ways of organizing knowledge .

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    7 o A ccommodation : It is the modification of existing schemes to permit the incorporation of new events or knowledge . o E quilibration : It is the creation of an equilibrium, or balance, between assimilation and accommodation . Piaget’s Stages of Cognitive Development • Piaget identified four major stages of cognitive development: s ensorimotor , p reoperational , c oncrete operational , and f ormal operational . • Because Piaget’s theory focuses on cognitive development, its applications are primarily in educational settings . • Piaget’s theory ends with formal operational thought. Evaluation • Many researchers , using a variety of methods, find that Piaget may have underestimated the ages when children are capable of doing certain things . o It also appears that many cogniti ve skills may develop gradually and not in distinct stages . Information - Processing Theory • Many psychologists and educators speak of people as having working or short - term memory and a more permanent long - term memory (storage). o Th u s , m any cognitive psychologists f ocus on information processing in people — the p rocesses by which people encode (input) information, store it (long - term memory), retrieve it (place it in short - term memory), and manipulate it to solve problems . • People’s strategies for solving problems are sometimes referred to as their “mental programs” or “software . ” o In this computer metaphor, people’s brains are the “hardware” that runs their mental programs . o People ’s brain s — containing billions of brain cells called neurons — become their most “personal” computer s . • When psychologists who study information processing contemplate cognitive development, they are likely to talk in terms of the size of the person’s short - term memory and the number of programs she or he can run simultaneously .

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    8 D. The Biological Perspective • The biological perspective directly relates to p hysical development : to gains in height and weight ; development of the brain ; and developments connected with hormones, reproduction, and heredity . Evolutionary Psychology and Ethology: “Doing What Comes Naturally” • Evolutionary psychology and ethology were heavily influenced by the 19 th - century work of Charles Darwin and by the work of 20 th - century ethologists Konrad Lorenz, and Niko Tinbergen . • Ethology — study of behaviors that are specific to a species — is c oncerned with instinctive , or inborn , behavior patterns . • The field of evolutionary psychology studies the ways in which adaptation and natural selection are connected with mental processes and behavior . o One of the concepts of evolution ary psychology is that not only physical traits but also patterns of behavior, including social behavior, evolve and are transmitted genetically from generation to generation . o The behavior patterns are termed instinctive or species - specific because they evolved within certain species . • The nervous systems of most, and perhaps all, animals are “prewired” to respond to some situations in specific ways . o These behaviors are “built in,” or instinctive. o They are also referred to as inborn f ixed action patterns (FAPs) — a stereotyped pattern of behavior that is evoked by a “releasing stimulus . ” • During prenatal development, genes and sex hormones are responsible for the physical development of female and male sex organs. • Research into the ethological perspective suggests that instinct may play a role in human behavior . E. The Ecological Perspective • Ecology is the b ranch of biology that deals with the relationship s between living organisms and the environment . • The e cological systems theory of development a ddresses aspects of psychological, social, and emotional development as well as aspects of biological development . o Ecological systems theorists explain development in terms of the interaction between people and the settings in which they live (Bronfenbrenner & Morris, 2006) . • According to Urie Bronfenbrenner (1917 - 2005) , for example, people need to fo cus on

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    9 the two - way interactions between the child and the parents, not just maturational forces (nature) or child - rearing practices (nurture) . o Bronfenbrenner suggested that people can view the setting or contexts of human development as consi sting of multiple systems, each embedded within the next larger cont ext (Bronfenbrenner & Morris, 2006 ; Losike - Sedimo, 2018 ) . • From narrowest to widest, Bronfenbrenner’s systems are as follows : o M icrosystem : This involves the interactions of the child and other people in the immediate setting , such as the home, the school, or the peer group . o M esosystem : This involves the interactions of the various settings with in the microsystem . For instance, the home and the school interact during parent – teacher conferences . o E xosystem : This involves the institutions in which the child does not directly participate but which exert an indirect influence on the child . For example, the school board is part of the child’s exosystem because board members put together programs for the child’s education, determine what textbooks will be acceptable, and so forth. o M acrosystem : This involves the interaction of children with the beliefs, values, expectations, and lifestyles of their cultural setting s . o C hronosystem : This considers the changes that occur over time . For example, the effects of divorce peak about a year after the event, and then children begin to recover . F. The Sociocultural Perspective • The s ociocultural p erspective teaches that p eople are social beings who are affected by the cultures in which they live . • Developmentalists use the term sociocultural in a couple of different ways . o One refers quite specifically to the sociocultural theory of Russian psychologist Lev Semenovich Vygotsky (1896 - 1934) . o The other addresses the effect of human diversity on people, including such factors as ethnicity and gender . Vygotsky’s Sociocultural Theory • Whereas genetics is concerned with the biological transmission of traits from generation to generation, Vygotsky’s (1978) theory is concerned with the t ransmission of information and cognitive skills from generation to generation . o Like Piaget, Vygotsky sees the child’s functioning as adaptive, and the child adapts to his or her social and cultural interactions . • Key concepts in Vygotsky’s theory include the following :

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    10 o Z one of proximal development (ZPD) : This refers to a r ange of tasks that a child can carry out with the help of someone who is more skilled , as in an apprenticeship . o Scaffolding : This is Vygotsky’s term for temporary cognitive structures or methods of solving problems that help the child as he or she learns to function independently . G. Human Diversity • The sociocultural perspective asserts that people cannot understand individuals without awareness of the richness of their diversity (Markus, 2016 ; Tatto et al., 2017 ) . o For example, people differ in their ethnicity (cultural heritage, race, language, and common history ), their gender, and their socioeconomic status . • Studying diversity is important so that students have appro priate educational experiences. o To teach students and guide their learning, educators need to understand children’s family values and cultural expectations . • Gender is another aspect of human diversity. o It is the psychological state of being male or being female, as influenced by cultural concepts of gender - appropriate behavior. o Expectations of females and males are often polarized by cultural expectations. o Males may differ from females in some respects, but history has created more burdens for women than men as a result. o Historically, females have been discourage d from careers in the sciences, politics, and business. o Women today earn more than half of the undergraduate degrees in the so - called STEM field of biology, chemistry and mathematics (Cheryan et al., 2017). o Women are making inroads into academic and vocational spheres such as medicine, law engineering, and the military — traditionally male fields. o Most college students in the United States are female, but there remain many parts of the world in which women are prevented from obtaining an education (Yousafazi & Lamb, 2013). III. Controversies in Developme nt A. The Nature - Nurture Controversy • Researchers are continually trying to sort out the extent to which human behavior is the result of nature (heredity) and of nurture (environmental influences) . o Scientists seek the natural causes of development in children’s genetic heritage,

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    11 the functioning of the nervous sy stem, and in maturation . o Scientists seek the environmental causes of development in children’s nutrition, cultural and family backgrounds, and opportunities to learn about the world, including cognitive stimulation during early childhood and formal education . • Today, nearly all researchers agree that nature and nurture play important roles in nearly every area of development . B. The Continuity - Discontinuity Controversy • Some developmentalists view human development as a continuous process in which the effects of learning mount gradually, with no major sudden qualitative changes . o In contrast, other theorists believe that a number of rapid qualitative changes usher in new stages of development . • Stage theorists such as Sigmund Freud and Jean Piaget saw development as discontinuous . o They saw biological changes as providing the potential for psychological changes . • Certain aspects of physical development do occur in stages . o However, psychologists disagree on whether developments in cognition occur in stages . C. The Active - Passive Controversy • Historical views of children as willful and unruly suggest that people have generally s een children as active, even if mischievous (at best) or evil (at worst) . o John Locke introduced a view of children as passive beings (blank tablets); experience “wrote” features of personality and moral virtue on them . • At one extreme, educators who view children as passive may assume that they must be motivated to learn by their instructors . o At the other extreme, educators who view children as active may assume that they have a natural love of learning . • These debates are theoretical . o Scientis ts value theory for its ability to tie to gether observations and suggest new areas of investigation , but scientists also follow an empirical approach . o That is, they engage in research methods to find evidence for or against various theoretical positions . IV. How do We Study Development? • Strong arguments or reference to authority figures are not evidence. • Scientific evidence is obtained only by gathering sound information and conducting

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    12 research. A. Gathering Information • Researchers use various methods to gather information . o For example, they may ask teachers or parents to report o n the behavior of children, use interviews or questionnaires with adults, or stud y statistics compiled by the government or the United Nations . N aturalistic O bservation • Naturalistic - observation studies are conducted in “the field ” ; that is, in the natural, or real - life, settings in which they happe n . o In f ield studies , investigato rs observe the natural behavior of children in settings such as homes, playgrounds, and classrooms a nd try not to interfere with it . The Case Study • The case study is a carefully drawn account of the behavior of an individual . o Parents who keep diaries of their children’s activities are involved in informal case studie s . • In addition to direct observation, case stud ies may include questionnaires, standardized tests — a test in which an individual’s score is compared to the scores of a group of similar individuals — and interviews . B. C orrelational : Putting Things Together • Researchers u se the correlational method to determine whether one behavior or trait being studied is related to , or correlated with , another . • C orrelation coefficient is a number ranging from +1.00 and – 1.00 that expresses the direction (positive or negative) and strength of the relationships between two variables . • P ositive correlat ion is a relationship between two variables in which one variable increases as the other increases . • Negative correlation is a relationship between two variables in which one variable increases as the other variable decreases . Limitations of C orrelational Information • Correlational information can reveal relationship s between variables , but it d oes not

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    13 show cause and effect . • It may seem logical to assume that exposure to violent media makes people more agg ressive, but it may also be that more aggressive people choose violent media . o This research bias is termed a selection factor . C. The Experiment: Trying Things Out • The experiment is the preferred method for investigating questions of cause and effect . • In the experiment , a group of research participants receives a treatment and another group does not . o The subjects are then observed to determine whether the treatment changes their behavior . • Experiments are usually undertaken to test a hypothesis — a proposition to be tested . Independent and Dependent Variables • I ndependent variable is a variable whose presence is manipulated by the experimenters so that it s effects can be determined . • D ependent variable is a measure of an assumed effect of an independent variable . Experimental and Control Groups • Subjects in the experimental group receive the treatment , whereas subjects in the control group do not . o All other conditions ar e held constant for both groups . Random Assignment • Subjects should be assigned to experimental or control groups on a chance or random basis. • Ethical and practical considerations prevent researchers from doing experiments on the effects of many life circumstances , such a s divorce or different patterns of child rearing . • When experiments cannot ethically be performed on humans, researchers sometimes carry them out with animals and try to generalize the findings to humans . D. Longitudinal Research: Studying Development over Time • In l ongitudinal research , the s ame people are observed repeatedly over time , and changes in development , such as gains in height or changes in mental a bilities, are

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    14 recorded . • In c ross - sectional research , c hildren of different ages a re observed and compared . o It is assumed that when a large number of children are chosen at random, the differences found in the older age groups are a reflection of how the younger children will develop, given time . Longitudinal Stud ies • The Terman Studies of Genius, begun in the 1920s , tracked children with high IQ scores for more than 50 years . o M ale subjects , but not female subjects, went on to high achievement s in the professional world . o Contemporary studies of women show that women w ith high intelligence generally match the achie vements of men and suggest that women of the earlier era were held back by traditional gender - role expectations . • Most longitudinal studies span months or a few years, not decades. o For example, briefer longitudinal studies have found that the children of divorced parents undergo the most severe adjustment problems within a few months of the divorce, peaking at about a year. • L ongitudinal studies have drawbacks . o For example, it can be d ifficult to enlist volunteers to participate in a study that will last a lifetime . o Many subjects fall out of touch as the years pass; others die . Cross - Sectional Studies • Because of the drawbacks of longitudinal studies, most research that compares children of different ages is cross - sectional . • A major challenge to cross - sectional research is the cohort effect . o A c ohort is a group of people born at about the same time . o As a result, they experience cultural and other events unique to their age group . o In other words, children and adults of different ages are not likely to have shared similar cultural backgrounds. • Children of past generations also grew up with different expectations about gender roles and appropriate social behavior. o Women in the Terman study generally chose motherhood over careers because of the times. • In longitudinal studies, researchers know that they have the same individuals as they have developed over 5, 25, even 50 years or more. o In cross - sectional research, researchers can only hope that they will be

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    15 comparable. Cross - Sequential Research • Cross - sequential research combines the longitudinal and cross - sectional methods so that many of their individual drawbacks are overcome . • In the cross - seq uential study, the full span of the ideal longitudinal stu dy is broken up into convenient segments . • Assume that researchers wish to follow the attitudes of children toward gender roles from the age of four through the age of 12 . o The typical longitudinal study would take eight years . o Researchers can, however, divide this eight - year span in h alf by attaining two samples of children (a cross - section) instead of one: f our - year - olds and e ight - year - olds . • An obvious advantage to this collapsed method is that the study is comp leted in four years rather than eight years . o Still, the t esting and retesting of samples provides some of the continuity of the longitudinal study . • By observing both samples at the age of eight (a time lag comparison), researchers can also determine whether they are, in fact, comparable or whether the four - year difference in their birth date is associated with a cohort effect . E. Ethical Considerations • Researchers adhere to ethical standards that are intended to promote the dignity of the individual, foster human welfare, and maintain scientific integrity . • These standards also ensure that they do not use methods or treatments that harm subjects . o Researchers are not to use methods that may do physical or psychological harm. o Participants (and parents, if participants are minors) must be informed of the purposes of the research and about the research methods. o Participants must provide voluntary consent to participate in the study. o Participants may withdraw from the study at any time, for any reason o Participants should be offered information about the results of the study. • These guidelines present researchers with a number of hurdles to overcome before proceeding with and while conducting research, but because they protect the welfare of participants, the guidelines are valuable.

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    16 Discussion Topics Nature or Nurture? F ew traits are influenced purely by nature or nurture. Nature seems to dictate predominantly physical characteristics, such as blood type and eye color. By contrast, nurture influences learned abilities such as the specific language that one speaks. Babies are born with the ability to understand all the phonemes in the world’s languages . But by six months , they can only distinguish the phonemes in the languages being spoken around them. Most characteristics are influenced by a combination of nature and nurtu re. Point out to students that most psychological traits are influence d by both of these forces, but physical characteristics may also be a result of nature and nurture. For instance, weight is influenced by a person’s genetic makeup and by the diets in their environment. Everyday Examples of Classical Conditioning and Operant Conditioning Help students understand how classical conditioning affects their behavior by pointing out a few everyday examples. This can also help students master the confusing terminology associated with classical conditioning. Point out that this is really a learnin g of association. Following are some example s . • Thunderstorms o US = loud clap of thunder o UCR = jump or tense up o CS = lightning o UCR = tense up • Fast - food commercial o US = picture of juicy, de licious burger o UCR = hunger or salivation o CS = commercial jingle or song o UCR = hunger Note : Unlearned or unconditioned stimulus (US), unlearned or unconditioned response (UCR, learned or conditioned stimulus (CS) Operant conditioning is learning the effects that a particular behavior incurs, whether that is a reinforcement or a punishment. Stress that reinforcements increase the frequency of a behavior and can be positive (something added) or negative (something taken away). Explain that the positive and negative should be associated with addition or subtraction, not with good or bad . The f ollowing are some everyday examples . • Positive reinforcement: A teenager cleans her room to earn allowance.

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    17 • Negative reinforcement: A teenager cleans her room to stop the annoying nagging of her parents. Punishments decrease the frequency of a behavior and can be either positive or negative. • Positive punishment: A teenager is given additional chores for failing to clean her room. • Negative punishment: A teenager is grounded for failing to clean her room, that is, her social life is removed. Note that a student who is sent to his room that is filled with gadgets, such as a TV, a computer , and an iPod, may not be experiencing a punishment . Vygotsky vs. Piaget in Teaching The developmental theories of Piaget and Vygotsky have implications for education. Have students discuss the following questions in terms of the perspectives of each theorist: Would Piaget or Vygotsky see the value of peer tutoring ? How much teacher intervention should occur in discovery learning? Which theorist provides a basic framework for helping teachers to know what level of educational material is appropriate to teach to children of various ages? What are the strengths of thi s perspective , and what a re its limitations? Collecting Data While studying development, researches use various methods to gather information. According to the text, researchers might ask the parents about the behavior of their children. Also, information about the development can be achieved by observation. What ot her methods can researchers use to gather relevant data, while studying development? Can they use survey methods? What would be the targeted audience for such a survey? Does the data from already available research stay true to the changing conditions and trends in the society? Can one rely on the information that is already there? Discus s the different methods th at are available for collecting data and their advantages over the ones discussed in this chapter. Class Activities an d Projects Designing Studies There are many ways to examine issues of interest to child development. One issue that has often been investigated is the theory that watching violent TV shows causes aggression in children. Have students (either individually or in small groups) explain ho w they would study this using the methods given below. 1. Naturalistic observations: Where would you conduct these observations? Wha t behaviors would you look for? 2. Case study: What kinds of behaviors would interest you ? 3. Correlational study: What are the variables you are correlating? What would a positive

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    18 correlation indicate? What would a negat ive correlation indicate ? 4. Experimental study: What is the i ndependent v ariable (IV) ? What is the d ependent v ariable (DV) ? What is the experimental group? What is the treatment group? Make sure students discuss what evidence would support and contradict the theory, as well as the pros and cons of each methodology. Modifying Child Behavior Using the Principles of Operant Conditioning Have students write a short paper making recommendations to a parent dealing with their two - year - old’s temper tantrums to get a cookie in the grocery store. Make sure students identify parent responses that would reinforce the tantrums and make them increase (e.g., giving attention to the child or giving him or her the cookie) , as well as behaviors that would extinguish the behavior (e.g., ignoring them). Also, have students include a section on the possible consequences of spanking i n this situation . A rev iew by E. Gershoff (2002) is available in Psychological Bulletin, 128(4), 539 - 579 which students can use for this activity. Child Rearing Over Three Generations Have students interview their parents and grandparents about their experiences as children . Include in the interview such parenting practices as sleeping arrangements, infant feeding, discipline, household chores and responsibilities, after school activities, and rules for dating in adolescence. Encourage students to be creative when they think about other changes and /or differences for how children experienced childhood, even in recent times. Have students organize their findings into a chart ; list the ir e xperiences down the left - hand side of the paper and the ir three generations across the top. Have students highlight the differences that surprised them the most. Scaffolding in Real Life : Assembling Puzzles with Children If possible, invite children of various ages to class (i.e., a two - year - old, four - year - old, and six - year - old). Have students help the children put together age - appropriate puzzles. Then have students discuss the ways in which they helped to scaffold the children ’s thinking . Students will notice that the degree of assistance given to the younger children was more (perhaps showing them where the pieces go) when compared with the older children (perhaps only suggesting to start with the outside edges). This can also work as a class discussion if child participants are not available. Demonstration of C lassical Conditioning : 3, 2, 1, POP!

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    19 A simple demonstration can help students grasp the concepts involved in classical conditioning. Kohn and Kalat (1991) discussed an activity involving several air - filled balloons and a long dart or pin. To replicate this activity, students should inflate the balloons as much as possible so they will easily pop. Tape the balloons to a table in front of the class. Ask students to pay attention to their responses as you conduct the demonstration. Then, count down “3, 2, 1 , ” and pop the first balloon (if you are in a large auditorium, try doing this activity near a microphone so that the loud pop produces a startle response) . Repeat this for the next few balloons. On the last balloon, count down, but then miss the balloon. Most students will actually not flinch to the last countdown. Ask the students to describe their responses. Then, help students to identify the aspects of classical conditioning: UCS = loud pop ping sound, UCR = flinching or other startle reaction, CS = countdown or hand movement, UCR = clinching muscles to prevent flinching . S tudents may have t rouble identifying th ese components. Correlational Research and the Effects of Divorce on Children Have students work through the following research questions concerning the effects of divorce on children . This activity can be used as a way of expanding their understanding of research design and related concepts (naturalistic , correlational , experimental designs, developmental change investigation, independent and dependent variables, cause and effect, confounds, and ethical considerations) . 1. Why do we think there might be consequences of divorce on child development? What kinds of naturalistic observational research may have supported these conclusions? 2. What might be some of the specific consequences of divorce on child development? What kinds of correlational studies might be conducted by developmental psychologists to examine whether or not there were reliable and valid relations hips between divorce and these consequences? What are the possible confounding variables in this type of research? 3. What might be some of the issues concerning age differences in relationships between divorce and negative consequences? How could these be examined? 4. What kind of evidence might suggest that divorce causes negative consequences? What other explanations might there be for any correlational findings between negative consequences and divorce? What kind of research needs to be conducted to determine cause and effect in this case? In t his research , what is ( are) the independent variable(s) , and what is ( are) the dependent variable (s) ? 5. In regard to ethical concerns, w ould any of this research be questionable? What might those be , and how should a researcher deal with them? Theoretical Positions of Developmental Theories One way for students to appreciate the similarities and differences of the many developmental theories presented in this chapter is to examin e the stance each theory takes on the controversies

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    20 of child development ( i.e. , nature - nurture, active - passive, and continu ity - discontinu ity ). The theories can be discussed in s mall groups or as a class. Nature - Nurture Active - Passive Continu ity - Discontinu ity Freud’s Theory of Psychosexual Development Both Passive Discontinuous Erikson’s Theory of Psychosocial Development Both Active Discontinuous Watson’s Behaviorism Nurture Passive Continuous Bandura’s Social Cognitive Theory Nurture Active Continuous Piaget’s Cognitive - Developmental Theory Both Active Discontinuous Information - Processing Theory Both Active Continuous Lorenz’s Ethology Both ( primarily nature but early experience is necessary) Passive Discontinuous (due to early critical period) Bronfenbrenner’s Ecological Systems Theory Both Active Continuous Vygotsky’s Sociocultural Theory Both Active Continuous Conducting Research Ask student s to select so me negative ( coming late to the class ) and positive (taking notes in the class) behavior s that are common among students . After selecting certain types of behaviors, ask students to make a note of the governing factors of such behaviors . What methods would they use to assess such behaviors? If time permits, students should conduct a survey in their class or in groups to identify the governing factors of the behaviors chosen.

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    21 Answer K ey: Truth or Fiction? As an introduction to each chapter, several statements are presented for students ’ consideration. This is an excellent first class activity. For each question , you can ask students how confident they are about their answers and, if they were confident (especially about questions they got wrong), ask them where they thought their knowledge about the topic came from — personal experience , a nother person , a n expert perhaps , i ntuition , or c ommon sense . Use this discussion to highlight the importance of investigation and hypothesis testing in developmental psychology for accurate understanding of behavioral phenomena. Use of the scientific method involves collecting data on more than one person . T he observations need to be made by an unbiased observer, and reliable and valid measurement instruments need to be used . In addition, care needs to be taken to control for confounding influences. Many times over the course of the semester, students will feel they already “know” something about a topic in child development only to find that the research does not support their position. Remind them about this discussion early and often . 1. During the Middle Ages, children were often treated as miniature adults. Truth . This does not mean that they were given more privileges, however. Instead, more was expected of them ( 1 - 2 ) . 2. Nail biting and smoking cigarettes are signs of conflict experienced during early childhood. Fiction . Actually, there is no evidence that nail biting and smoking cigarettes are signs of conflict experienced during early childhood. The statement must therefore be considered “fiction ” ( 1 - 2a ) . 3. Research with monkeys has helped psychologists understand the formation of attachment in humans. Truth . Researchers have exposed monkeys and other nonhuman animals to conditions that would be unethical to use with humans ( 1 - 4c ) . 4. To learn how a person develops over a lifetime, researchers have tracked some individuals for more than 50 years. Truth . It is tru e that researchers have tracked some individuals for more than 50 years to learn how a person develops over a lifetime. The Terman study did just that. What are the advantages and disadvantages of longitudinal research as compared with cross - sectional research? ( 1 - 4d )

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    22 Additional Reading Material Kohn, A. & Kalat, J. W. (199 2 ). Preparing for an important event: Demonstrating the modern view of classical conditioning. Teaching of Psychology, 19(2), 100 – 102. Video Suggestions Theories of Development (1997, Insight Media, 29 minutes) This video provides an overview of the cognitive, psychosexual, psychosocial, behaviorist, social - learning, and sociocultural theories of child development. Piaget’s Developmental Theory: An Overview (1989, Davidson Films, 25 minutes) This video provides a good introduction or review of basic concepts, including interviews with children by David Elkind. Erik Erikson: A Life’s Work (199 1 , Films Media Group , 38 minutes) This video integrates biographical information about Erikson with an overview of his eight - stage psychosocial theory of human development. B. F. Skinner: A Fresh Appraisal (1999, Davidson Films, 40 minutes) This video includes both archival and recent footage and is narrated by Murray Sidman. It clarifies some myths about behaviorism in the context of presentation of his theory and research. His Own Best Subject: A Visit to B.F. Skinner’s Basement (2000, Davidson Films, 20 minutes) This video consists of Skinner’s daughters discuss ing their father ’s affection toward them and the kind of attention he gave to them . They also give a tour of the basement in which he used to wr i te. Vygotsky’s Developmental Theory: An Introduction (1994, Insight Media, 2 8 minutes) This video provides a presentation of the basic concepts and vocabulary of Vygotsky’s constructivist educational approach to development. Innocence: What is a Child? (1997, Films for the Humanities and Social Sciences, 54 minutes) This video provides historical perspectives on the construct of childhood innocence from the la te nineteenth century to the present. Total Baby (1995, Filmakers Library , 59 minutes) This video discusses childrearing as a reflection of societal and cultural views of the era and examines ideas about children by different theorists ( Aristotle , Dr. Spock ) .

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    23 Research Methods for the Social Sciences (1995, Insight Media, 33 minutes) This video provides an overview of the key concepts of experimental design and reviews the different steps of the scientific method. Research Methods in Psychology (2001, Insight Media, 28 minutes) This video provides an overview of the observational and descriptive research designs (uses example of correlational findings on aggressive behavior and video games). Key Terms Developmental p sychology Life - span perspe ctive Behaviorism Maturation Psychosexual development Stage theory Psychosocial development Life crisis Identity crisis Classical conditioning Operant conditioning Reinforcement Positive reinforcer Negative reinforcer Extinction Social cognitive theory Cognitive - developmental theory Scheme Adaptation Assimilation Accommodation Equilibration Ethology Evolutionary psychology Fixed action pattern (FAP) Ecology Ecological systems theory Microsystem Mesosystem Exosystem Macrosystem Chronosystem Zone of proximal development (ZPD) Scaffolding Nature Nurture Empirical Naturalistic observation Case study Standardized test s Correlation coefficient Positive correlation Negative correlation Experiment Hypothesis Independent variable Dependent variable Experimental group Control group Longitudinal research Cross - sectional research Cohort effect Cross - sequential research Time lag

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    1 Chapter 2 H e r e d i t y a n d P r e n a t a l D e v e l o p m e n t Chapter Overview This chapter provides an overview of the biological processes of heredity and conception, including all of the basic structures (chromosomes, genes, and DNA) and processes (mitosis, meiosis, fertilization, and implantation) involved in the formation of a new human being. Students will learn the different causes and types of chromosomal and genetic abnormalities. The relationship between genotype and phenotype in developmental outcome is described, and the potential disorders resulting from various chromosomal and genetic abnormalities are discussed. Research strategies for examining the contribution of genes and environment to development are introduced. The chapter includes a discussi on of infertility and genetic counseling, alternative pregnancy methods, and parental attempts to select the gender of their child. A brief discussion of the benefits of adopting children is presented. The chapter also describes the preimplantation genetic diagnosis process. Students will be able to compare the different stages of prenatal development (germinal, embryonic, and fetal), after reading this chapter. Sexual differentiation is explained in detail. The role of amniotic sac, amniotic fluid, and pla centa in the development and delivery process is presented. The changes in the fetus throughout the pregnancy cycle are explained. Students will be able to identify the different types of teratogens that can affect the health of the developing fetus as wel l as the stage of development where harm can occur, after reading this chapter. This chapter describes the impact of drugs that are the most likely to affect the healthy development of a fetus (aspirin, thalidomide, hormones, vitamins, heroin, methadone, m arijuana, alcohol, cocaine, caffeine, and cigarettes). The chapter concludes with a discussion of the environmental effects on the development of the fetus such as prenatal exposure to lead and the age of the parents at conception. Chapter Learning Objectives After reading the chapter, students should be able to accomplish the objectives given below. • E xplain the difference between a gene and a chromosome, and explain how a baby’s sex is determined • D escribe the processes of mitosis and meiosis • I dentify the difference between monozygotic and dizygotic twins and describe how they are developed • D escribe the process of genetic transmission, or how traits are passed from parents to children • D iscuss the causes and characteristics associated with chromosomal and genetic

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    2 abnormalities • E xplain how Down syndrome occurs as well as its physical markers • D escribe how sex - linked chromosomal abnormalities occur • I dentify and compare the different sex - linked chromosomal disorders (Klinefelter syndrome and Turner syndrome) • I dentify and compare disorders that have been contributed to genes (PKU, Huntington’s disease, Sickle - Cell Anemia, Tay - Sachs disease, and Cystic Fibrosis) • I dentify and compare sex - linked genetic abnormalities (hemophilia, Duchenne muscular dystrophy) • I dentify and explain different prenatal testing techniques used for various genetic disorders • D escribe how studies of kinship, adopted children, and identical (monozygotic) versus fraternal (dizygotic) twins are used to explore the relative influences of nature (heredity) versus nurture (environment) • E xplain the formation of eggs and sperm and where conception takes place • To define the following terms: “ova,” “endometrium,” “sperm cells,” and “spontaneous abortion” • D iscuss the causes of infertility and the methods that couples can use to conceive • D iscuss the benefits of adopting children • D escribe the preimplantation genetic diagnosis process • D efine and compare the different stages of prenatal development (germinal, embryonic, and fetal) • E xplain how sexual differentiation occurs • D escribe the role the amniotic sac, amniotic fluid, and placenta play in the development and delivery process • D escribe changes in the fetus throughout the pregnancy cycle • I dentify the different types of teratogens that can affect the developing fetus’ health as well as the developmental stage where harm can occur • D escribe the impact of drugs that are the most likely to affect the healthy development of a fetus (aspirin, thalidomide, hormones, vitamins, heroin, methadone, marijuana, alcohol, cocaine, caffeine, and cigarettes) • D escribe the environmental effects on the fetus’ development such as prenatal exposure to lead and/or the parents’ age at conception Chapter Outline The field of biology that studies heredity is called genetics . I. The Influence of Heredity on Development

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    3 • Genetic influences are fundamental in the transmission of physical traits, such as height, hair texture, and eye color. • Heredity appears to be a factor in almost all aspects of human behavior, personality, and mental processes ( Loehlin & Martin, 2018 ; Plomin & Haworth, 2009; Polderman et al., 2015 ). • Genetic factors are also involved in psychological problems such as schizophrenia, depression, and dependence on nicotine, alcohol, and other substances (Leonardo & Hen, 2006; Lewis et al., 2013; Viding et al., 2013). A. Chromosomes and Genes • Chromosomes are rod - shaped structures found in cells. • Genes are the biochemical materials that regulate the development of traits. o Some traits, such as blood type, appear to be transmitted by a single pair of genes, one of which is derived from each parent. o Other traits are polygenic , that is, determined by several pairs of genes. • Genes are segments of strands of deoxyribonucleic acid (DNA) — genetic material that takes the form of a double helix composed of phosphates, sugars, and bases. B. Mitosis and Meiosis • There are two types of cell division: mitosis and meiosis. • In mitosis , strands of DNA break apart, or “unzip.” o The double helix then duplicates. The DNA forms two camps on either side of the cell, and then the cell divides. o Each incomplete rung combines with the appropriate “partner” (i.e., G and C, A and T) to form a new complete ladder. The two resulting identical copies of the DNA strand separate when the cell divides; each becomes a member of a newly formed cell. o As a result, the genetic code is identical in new cells unless mutations — sudden variations in a heritable characteristic — occur through radiation or other environmental influences. • Sperms and ova (“egg cells”) are produced through meiosis , or reduction division. o In meiosis, the 46 chromosomes within the cell nucleus first line up into 23 pairs. The DNA ladders then unzip, leaving unpaired halves of chromosome. o When the cell divides, one member of each pair goes to each newly formed cell. Each new cell nucleus contains only 23 chromosomes, not 46 . E ach pair of chromosomes splits so that one member of each pair moves to the new cell. • When a sperm cell fertilizes an ovum, humans receive 23 chromosomes from their father’s sperm cell and 23 from their mother’s ovum, and the combined chromosomes

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    4 form 23 pairs. o Twenty - two of the pairs are autosomes — pairs that look alike and possess genetic information concerning the same set of traits. o The 23rd pair are sex chromosomes , which look different from other chromosomes and determine one’s sex. C. Identical and Fraternal Twins • Now and then, a zygote divides into two cells that separate so that each develops into an individual with the same genetic makeup. o These individuals are identical twins, or monozygotic (MZ) twins. • If the woman produces two ova in the same month and they are each fertilized by different sperm cells, they develop into fraternal twins, or dizygotic (DZ) twins . • As women reach the end of their childbearing years, ovulation — releasing of an ovum from an ovary — becomes less regular, resulting in a number of months when more than one ovum is released. D. Dominant and Recessive Traits • Each member of a pair of genes is termed as an allele . • When both of the allele for a trait, such as hair color, are the same, the person is said to be homozygous for that trait. • When the alleles for a trait differ, the person is heterozygous for that trait. • When the effects of both alleles are shown, there is said to be incomplete dominance or codominance. • When a dominant allele is paired with a recessive allele, the trait determined by the dominant allele appears in the offspring. o Dominant trait is a trait that is expressed. o Recessive trait is a trait that is not expressed when the gene or genes involved have been paired with dominant genes. • People who bear one dominant gene and one recessive gene for a trait are said to be carriers of the recessive gene. E. Chromosomal and Genetic Abnormalities • Chromosomal or genetic abnormalities can cause health problems. o Some chromosomal disorders reflect abnormalities in the 22 pairs of autosomes (such as Down syndrome); others reflect abnormalities in the sex chromosomes (e.g., XYY syndrome). o Some genetic abnormalities, such as cystic fibrosis, are caused by a single pair

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    5 of genes; others are caused by combinations of genes. o Diabetes mellitus, epilepsy, and peptic ulcers are multifactorial problems ; they reflect both a genetic predisposition and environmental contributors. F. Chromosomal Abnormalities Down syndrome • Down syndrome is usually caused by an extra chromosome on the 21 st pair, resulting in 47 chromosomes. • People with Down syndrome have characteristic features that include a rounded face, a protruding tongue, a broad, flat nose, and a sloping fold of skin over the inner corners of the eyes. Sex - Linked Chromosomal Abnormalities • A number of disorders stem from an abnormal number of sex chromosomes and are therefore called sex - linked chromosomal abnormalities . o Most individuals with an abnormal number of sex chromosomes are infertile. • Approximately one male in 500 has Klinefelter syndrome , which is caused by an extra X sex chromosome (an XXY sex chromosomal pattern). o XXY males produce less of the male sex hormone testosterone than normal males. • Approximately one girl in 2,500 has a single X sex chromosome and as a result develops Tu r ner syndrome . o The external genitals of such girls are normal, but their ovaries are poorly developed and they produce little estrogen — the female sex hormone produced mainly by the ovaries. • Approximately one girl in 1,000 has an XXX sex chromosomal structure, called Triple X syndrome. o Such girls are normal in appearance but tend to show lower - than - average language skills and poorer memory for recent events. G. Genetic Abnormalities Phenylketonuria • The enzyme disorder phenylketonuria (PKU) is transmitted by a recessive gene and affects about one child in 8,000. • Children with PKU cannot metabolize an amino acid called phenylalanine, so it

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    6 builds up in their bodies and impairs the functioning of the central nervous system, resulting in mental retardation, psychological disorders, and physical problems. Huntington’s Disease • Huntington’s disease (HD) is a fatal, progressive degenerative disorder and a dominant trait affecting approximately one American in 18,000. • Physical symptoms include uncontrollable muscle movements. • Psychological symptoms include loss of intellectual functioning and personality change. Sickle - Cell Anemia • Sickle - cell anemia is caused by a recessive gene. • In sickle - cell anemia, red blood cells take on the shape of a sickle and clump together, obstructing small blood vessels and decreasing the oxygen supply. Tay - Sachs disease • Tay - Sachs disease is also caused by a recessive gene. • It causes the central nervous system to degenerate, resulting in death. Cystic Fibrosis • Cystic fibrosis , also caused by a recessive gene, is the most common fatal hereditary disease among European Americans. • Children with the disease suffer from excessive production of thick mucus that clogs the pancreas and lungs. Sex - Linked Genetic Abnormalities • Some genetic defects, such as hemophilia — a genetic disorder in which blood does not clot properly — are carried on only the X sex chromosome. o For this reason, they are referred to as sex - linked genetic abnormalities . • One form of muscular dystrophy , Duchenne muscular dystrophy , is sex linked. o Muscular dystrophy is characterized by a weakening of the muscles, which can lead to wasting away, inability to walk, and sometimes death. H. Genetic Counseling and Prenatal Testing

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    7 • Genetic counselors compile information about a couple’s genetic heritage to explore whether their children might develop genetic abnormalities. • Prenatal — before birth — testing can indicate whether an embryo or fetus is carrying genetic abnormalities. • Although amniocentesis and chorionic villus sampling is discussed next, it should be noted that their use is declining due to blood testing and ultrasounds becoming more sophisticated and providing a clearer picture early on in the pregnancy. Amniocentesis • Amniocentesis is usually performed on the mother at 14 - 16 weeks after conception, although many physicians now perform the procedure earlier. o In this fetal - screening method, the health professional uses a syringe (needle) to withdraw fluid from the amniotic sac. o The fluid contains cells that are sloughed off by the fetus. o The cells are separated from the amniotic fluid, grown in a culture, and then examined microscopically for genetic and chromosomal abnormalities. • Amniocentesis carries some risk of miscarriage — expulsion of an embryo or fetus before it can sustain life on its own, most often due to defective development — although the extent of the risk is unclear. Chorionic Villus Sampling • Chorionic villus sampling (CVS) is similar to amniocentesis but is carried out between the 9 th and 12 th week of pregnancy. o A small syringe is inserted through the vagina into the uterus and sucks out some threadlike projections (villi) from the outer membrane that envelops the amniotic sac and fetus. • CVS has not been used as frequently as amniocentesis because CVS carries a slightly greater risk of miscarriage. Ultrasound • Health professionals use sound waves that are too high in frequency to be heard by the human ear — ultrasound — to obtain information about the fetus. o These waves are reflected by the fetus, and a computer uses the information to generate a picture of the fetus. The picture is termed a sonogram . Blood Tests

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