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Developmental Psychology



Discuss the fundamental concern of developmental psychology.

    Developmental psychology is the study of change across the life span. Developmental psychologists focus attention on physical, cognitive, and social development.

Provide examples of the following three dimensions of development: growth, differentiation, and orderly progression.

    Although the brain is only 25% of adult size at birth, it grows to 90% of adult size by the age of 5. Regarding differentiation, the many organs of the body (e.g., the brain, heart, and lungs) have their origin in a single cell. Finally, regarding orderly progression, young children creep before crawling, and utter single words before forming complex sentences.


Give examples of the nineteenth century belief that children were just small versions of adults.

    In the past, artists generally portrayed children as miniature adults, with adult clothing and facial features. Similarly, employment practices included the placement of children in jobs that fit their small physical stature; these same jobs are regarded as "adult" jobs today.


Discuss the effect on the study of developmental psychology of the perspective that children are qualitatively different from adults.

    First, this perspective generated interest in understanding children as distinct from adults. Second, the tendency to see children as unique has led many theorists to think about development as occurring in distinct stages.


Explain the difference between continuous and discrete models of development.

    Continuous models of development emphasize the occurrence of change in a cumulative, bit-by-bit fashion. Discrete models of development emphasize development through a series of qualitatively distinct phases that are often marked by critical periods.

Provide an example of discrete development.

    Language development is marked by critical periods. For instance, if a child learns a second language before age 10 , this will likely result in enhanced comprehension of the language's grammatical structure and the child speaking without an accent.



Discuss the three stages of prenatal development.

    The three stages of prenatal development are the germinal stage, the embryonic stage, and the fetal stage. During the germinal stage (the first two weeks after conception), the single-celled zygote transforms into a cluster of rapidly dividing cells. During the embryonic stage (from two weeks to two months), the embryo starts to display more recognizably human anatomical features and the majority of the major body organs become evident. Finally, during the fetal stage (from two months to birth), the human fetus continues to mature by rapidly developing organs, such as the brain and lungs, that will enable it to survive outside of the mother's body.

Define teratogen

    A teratogen is an agent (e.g., cigarette, alcohol, or cocaine) that affects the mother's body and can harm the developing embryo; teratogens have the potential to produce significant birth defects.

Discuss the cause of Fetal Alcohol Syndrome and its effects.

    Fetal Alcohol Syndrome results from excessive maternal drinking during pregnancy. Pregnant women who consume high levels of alcohol (more than five drinks per day) can give birth to offspring with reduced intelligence and birth defects.


Motor Development

Define reflexes.

    Reflexes are automatic behaviors such as sucking, rooting, grasping, stepping, and swimming.

Discuss the purpose of reflexes.

    Although the adaptive function of many reflexes is unclear (e.g., the Babinski reflex), others (e.g., sucking or grasping reflexes) may help the newborn adapt and survive outside the womb.

Give examples of reflexes.

    One interesting reflex is the sucking reflex. Touching the infant's lips initiates sucking. When teamed with the rooting reflex, which turns the infant's head in the direction of a touch on its cheek, the two reflexes prepare the infant to find the mother's nipple and feed itself.

Define developmental milestones.

    Developmental milestones are average ages at which specific physical, social, or cognitive achievements are attained (e.g., walking by oneself occurs on average at 13 months).

Discuss the implications of developmental milestones for the assessment of normal physical development.

    Developmental milestones provide markers to assess normal development. However, because they are based on averages, a great deal of variation exists around the mean age at which children reach developmental milestones (e.g., not all children begin walking at 13 months). Abnormal development occurs only when children develop skills significantly earlier or later than expected.

The Growing Brain

Discuss brain growth during infancy and childhood.

    The infant brain is 25% of adult size. It continues to grow through approximately the sixteenth year; however, it achieves 90% development by ages 5 or 6.

The Developing Senses


Discuss infant visual acuity.

    At birth, vision is as poor as 20/600, making the newborn extremely nearsighted. Visual acuity reaches 20/100 by six months and normal adult level (20/20) in most children by the second year.

Define visual cliff.

    The visual cliff is an experimental apparatus designed to assess infant depth perception. It is an actual cliff covered by Plexiglas so that the infant can perceive depth without getting hurt by falling.

Discuss infant preferences for certain visual stimuli.

    When given a choice, infants prefer human faces to other objects, and can recognize the mother's face by three months.


Discuss infant auditory ability and preferences.

    Infants are born with better auditory ability than visual ability. Immediately after birth, they turn toward the source of a sound. Infants appear particularly sensitive to the human voice, and within days they can discriminate their mother's voice from the voices of strangers.

Taste and odor

Give examples of infant taste preference.

    Infants are born with a preference for sweet substances. However, at around four months, they develop a liking for salty foods.

Give examples of infant olfaction.

    Infants make facial expressions of disgust when smelling a rotten egg, and smile in presence of pleasant odors. As early as two weeks, they are capable of recognizing their mother's unique odor.


Define adolescence.

    Adolescence is roughly defined as the transition period between childhood and adulthood.

Discuss the role of sex hormones in adolescent development.

    In boys, the increase in testosterone initiates development in the testes and penis, and promotes secondary sex characteristics such as a deepening voice, facial hair, and muscular development. In girls, increasing levels of estrogen and other sex hormones instigate changes in the ovaries and uterus, as well as increases in breast size and widening of the pelvic bones. This generally also marks the beginning of menstruation.

Discuss the relationships among brain development, impulse control, and adolescent risk-taking behavior.

    The frontal lobes of the brain, implicated in planning and self-control, do not finish developing until the early twenties, making impulse control less reliable and risk-taking behavior more common in adolescence.


Discuss the widely held belief that adulthood is a period of decline in physical capacity.

    Between the middle twenties and early thirties, most physical capacities begin to decline. Reaction times and muscular strength decrease. The cardiovascular system becomes less efficient and respiratory capacity decreases. Appearance also changes, as skin wrinkles and hair grays, and decreases in metabolism make weight gain more likely. These changes influence our beliefs in adulthood as a period of decline in physical capacity.

Define menopause.

    Menopause is the cessation of menstruation and ovulation in women as estrogen production dwindles. Menopause typically occurs between the ages of 45 and 55. Males also experience a form of menopause, with decreased production of sperm cells resulting from reduced levels of testosterone.


Compare life span today to life span at the turn of the last century.

    At the turn of the twentieth century, only half of the U.S. population lived to be over age 65. Today, the majority of people are expected to live well into their seventies, and by the year 2030, it is estimated that there will be more people over the age of 65 than in any other age group.

The Aging Brain

Discuss neuronal death and aging.

    In late adulthood, many individuals will lose about 5% to 10% of their neurons. However, there may be little noticeable difference due to the brain's many billions of neurons and system redundancy (other parts of the brain backing up the parts losing neurons). Aging can also be associated with decline in availability of neurotransmitters such as dopamine, serotonin, acetylcholine, and norepinephrine; these deficiencies may contribute to many of the declines seen in aging (e.g., reduced motor capacity and memory ability).


Define dementia.

    Dementia is a type of cognitive impairment characterized by memory losses, confusion, and disorientation.

Define Alzheimer's disease.

    Alzheimer's Disease is a degenerative disorder of the central nervous system that causes severe mental and physical impairment and is eventually fatal.

Describe the general course of Alzheimer's disease and its likely outcome.

    Initially, the symptoms of Alzheimer's disease involve forgetfulness, particularly with respect to recent events. Eventually, as the disease progresses, the individual is no longer able to recognize family members or take care of himself or herself. Alzheimer's disease is fatal.

Discuss risk factors of Alzheimer's disease.

    The causes of Alzheimer's disease are only now being uncovered, and include such factors as genetics, exposure to certain metals and viruses, and perhaps exposure to strong electromagnetic fields.

Define stroke.

    A stroke, also known as a cerebral vascular accident, results when a particular section of the brain dies; this is caused by the loss of oxygen to that section resulting from arterial occlusion, such as the presence of an arterial blood clot.

The Aging Senses


Explain why so many senior citizens are farsighted.

    As we age, the lens of the eye thickens, precluding accommodation to nearby objects, resulting in farsightedness.


Discuss why three quarters of people over 75 years old have significant hearing impairment.

    Progressive, age-related hearing impairment results primarily from destruction of receptor cells (tiny hair cells found in the cochlea), caused by continued exposure to excessive noise.

Taste and odor

Discuss the relation between age-related declines in olfaction and the subjective experience of flavor.

    Subjective experience of flavor decreases with age, particularly after the age of 70, because of declines in olfactory sensitivity. The sensation of odor molecules with the ingestion of food is a key component of flavor.



Discuss the four types of activities of newborns.

    Newborns spend their days primarily sleeping (16-18 hours). The remainder of their days are spent crying or fussing (2-3 hours a day), and in alert (focused) and wakeful (moving but not focused) activity.

Discuss the developing cognitive capacities of infants.

    Infants are more competent than most believe. Almost immediately after birth, infants show preference for images that contain faces. After only three days, they recognize mother's voice and prefer it to the voices of others. As early as a week, they show preference for the mother's odor. And after only four months, they recognize their names.


Assimilation and Accommodation

Define schemata and provide an example.

    Schemata are cognitive (mental) representations of things that surround us. An example of a schema is "All things that fly are birds."

Define assimilation and provide an example.

    Assimilation refers to the fitting of an experience into an existing schema. For instance, the child who believes that all things that fly are birds points to an airplane and says, "Look mommy, a bird!"

Define accommodation and provide an example.

    Accommodation refers to modification of an existing schema to account for new situations. For instance, a child who believes all things that fly are birds points to an airplane and says, "Look mommy, a bird!" After the mother corrects the child, pointing to the distinction between birds and airplanes, and the child modifies the mental representation of birds to include only living creatures that fly, accommodation has occurred.

Piaget's Stages of Cognitive Development

Sensorimotor stage

Discuss why Piaget labeled his first stage of development the sensorimotor stage.

    According to Piaget, representations in the first stage of cognitive development (from birth to the age of 18 to 24 months) are tied to sensory experience and are very concrete.

Define object permanence.

    Object permanence refers to the awareness that objects continue to exist even when they are not present.

Preoperational stage

Discuss the relation of language to mental representation and symbolic capability.

    The progression from dependence on the concrete to abstract ability depends on mastery of language. Language allows children to represent physical objects mentally, by identifying physical objects with words.

Define the principle of conservation.

    The principle of conservation simply states that the physical properties of an object do not change with superficial changes in the appearance of the object.

Discuss why children in the preoperational stage are unable to master conservation tasks. Give an example.

    Despite increasing reliance on mental representation, cognition is still closely tied to concrete experience. Therefore, children in the preoperational stage are easily deceived by what they see. For instance, if two identical containers with equal amounts of liquid are placed before a preoperational child, and the child is asked which container has more liquid, the preoperational child is likely to say they are the same. However, when one of the containers is emptied into a container with a different shape, the child is likely to say one container contains more liquid than the other because he is deceived by the shape of the containers, even though the volumes remain the same.

Discuss Piaget's notion that children in the preoperational stage are egocentric.

    According to Piaget, preoperational children are unable to take the perspective of others, assuming that everyone sees the world as they do.

Concrete operations

Discuss the difference between concrete operational and preoperational thought.

    Operational thought is characterized by the ability to solve conservation problems, an increasing ability to employ relational terms that are not concrete (e.g., bigger or smaller than), decreased egocentrism, and the ability to categorize by a variety of characteristics including the abstract.

Provide an example of the ability of concrete operational children to employ abstract conceptual categories.

    When asked to sort objects (e.g., animals), preoperational children are likely to sort them by physical properties such as color or size, whereas concrete operational children can categorize objects by more abstract properties (e.g., domestic versus wild animals).

Formal operations

Discuss the characteristics of formal operational thought.

    Formal operational thought is characterized primarily by the ability to reason abstractly. Adolescents and adults reasoning at this level are also able to engage in deductive reasoning, both concretely and symbolically, and engage in hypothesis testing.

Piaget's Stages Reconsidered

Discuss evidence that suggests limitations to Piaget's theory.

    There are two points on which Piaget's theory should be reconsidered. First, Piaget underestimates the ability of very young children. For instance, employing the concept of habituation (i.e., losing interest in a consistent stimulus), children as young as four months have been shown to understand object permanence. Second, children as young as 2-1/2 years have been shown to be able to take the perspective of others, even though Piaget hypothesized that egocentrism is a characteristic of the preoperational child. This finding contradicts the notion that development is not continuous.

Was Piaget Wrong?

Discuss why Piaget can be considered both right and wrong about cognitive development.

    Piaget was wrong in that development appears to be a continuous process rather than occurring in stages. However, Piaget was correct in identifying the order of developmental milestones, and their order appears universal.

Adolescent Development

Define adolescent egocentrism and the concept of personal fable.

    Adolescent egocentrism is a cognitive state characterized by a belief in the uniqueness of one's thoughts and experiences, and a belief that others are preoccupied with the adolescent's thoughts and appearance.
    Personal fable refers to the belief that one's thoughts are fresh and unique.

Moral Reasoning

Kohlberg's model

Discuss the relationship between moral reasoning and cognitive development.

    According to Piaget, moral reasoning is a function of cognitive development, with children's reasoning being qualitatively different from that of adolescents and adults. Following from Piagetian theory, Lawrence Kohlberg proposed three levels of moral reasoning: preconventional, conventional, and postconventional. According to Kohlberg, reasoning at the preconventional level is characterized by avoidance of punishment and pursuit of reward. Reasoning in the conventional level of moral development is characterized by strict obedience to authority and social norms. Finally, reasoning at the postconventional level is motivated by democratic and personal ideals, even if they clash with normative beliefs.

Criticisms of Kohlberg's model

Discuss research findings and criticism related to Kohlberg's theory.

    Research findings support Kohlberg's ordering of the development of moral reasoning in children, and his hypothesis that moral development does not reverse once higher levels are attained. However, Kohlberg's theory is criticized for at least two reasons. First, according to Kohlberg, moral reasoning at the highest level is abstract but logically coherent. Critics assert that reasoning that is compassionate and respects human life should be regarded as the highest level. Second, it is unclear whether Kohlberg's theory addresses moral reasoning or moral justification.


Discuss the difference between longitudinal and cross-sectional research designs.

    Cross-sectional studies compare individuals of different ages at the same time in order to assess differences related to age. Longitudinal studies assess change in the same person over time.

Define cohort effect.

    Cohort effects are experiences that people within an age group share that have nothing to do with age-related development.

Discuss research findings concerning cognition and age from longitudinal and cross-sectional studies.

    When assessing cognitive abilities such as word fluency, inductive reasoning, and spatial orientation using cross-sectional design, younger individuals perform better than older individuals. When employing a longitudinal design, there appears to be stability in cognitive ability over time.

Discuss the difference between crystallized and fluid intelligence.

    Crystallized intelligence refers to knowledge that is accumulated and stored. Fluid intelligence refers to the ability to reason abstractly, solve logical problems, and make quick inferences.

Define wisdom.

    Wisdom is identified with practical knowledge and expertise gained from experience.



Studying Attachment

Define attachment.

    Attachment refers to the bond between children and their parents or caregivers.

Discuss Mary Ainsworth's Strange Situation test.

    In Mary Ainsworth's research, a mother was instructed to go with her infant into an unfamiliar room; after a short while, the mother slipped out of the room, leaving the infant alone to play in the room (strange situation). The mother was reunited with the child a short time later. Ainsworth was interested in the child's response to mother's return.

Discuss the three attachment styles Mary Ainsworth identified in her research.

    Ainsworth identified three attachment styles. Securely attached children were inquisitive while mother was present, mildly distressed when she left, and ran to greet her when she returned. Avoidant children were not demonstrably upset when mother left the room, did not seek her out when she returned, often ignoring her and continuing to play. Ambivalent children tended to become extremely agitated after they learned of their mother's departure, and were not comforted upon her return, resisting instead any attempts to calm them down.

Implications for Later Development

Discuss the implications for later social and emotional development for securely attached children.

    Researchers have found that securely attached children are more likely to be socially competent and less likely to suffer social or emotional problems later in life than adults raised with less personal attention from adults or who did not form close bonds with adult caregivers.

Discuss the implications for later development of extensive participation in day care.

    Most recent studies indicate that the psychological impact of daycare on young children is minimal.

Developing Attachment

Discuss the instinct view of attachment formation.

    Proponents of the instinct theory of attachment believe a critical period exists for attachment to an adult caregiver. Because human infants are so helpless, attachment to an able caregiver would be highly adaptive to insurance of survival. Advocates of instinct theory also believe that adults are preprogrammed to respond compassionately to infant smiles and cries.

Explain how the research findings of Harry Harlow and his colleagues contradict the reinforcement explanation of attachment.

    Harry Harlow found that the rhesus monkeys studied preferred the comfortable mother without a source of food to the wire mother with the artificial nipple for feeding. This finding contradicts the reinforcement explanation that predicts attachment results from provision of rewards (e.g., food and safety) from caregivers, as infant monkeys seemed to prefer comfort to food.

Discuss the relationship between temperament and the parent-child relationship during infancy.

    Temperament refers to relatively consistent patterns of emotion, activity, and sociability exhibited in babies almost from birth. Temperament can interfere with the formation of secure attachment, particularly when the child is considered "difficult." Difficult babies cry and fuss more than other babies.


Define self-concept.

    Self-concept refers to an individual's mental image of himself or herself, including perceived abilities and capabilities, and other self-descriptions, including beliefs about appearance, goals, and values.

Discuss assessment of infant sense of self.

    To assess infant sense of self, researchers commonly mark an infant's nose with red dye, a technique known as the rouge test, and place the infant before a mirror. If the infant notices the mark and touches his own nose, it is concluded that the infant is self-aware.

Discuss the ages at which developmental milestones in self-concept appear.

    According to researchers, infants achieve self-awareness at about 15 months. Children begin to use personal pronouns indicative of self-understanding (e.g., "I," "me," and "you") at around 22 months. At around the same time, they begin labeling objects as theirs.

Describing the Self

Compare self-conceptions of children and adolescents.

    Consistent with cognitive development, young children tend to describe themselves in concrete terms (e.g., physical appearance or possessions), older children begin to describe themselves in terms of traits, and adolescents describe themselves in terms of goals, values, and other abstractions.

Determine if there are cross-cultural differences in the way individuals respond to the McGuire "Who am I?" instrument.

    Based on research findings employing McGuire's "Who am I?" test, children in cultures valuing interdependence describe themselves in terms of social roles and relationships, whereas children in cultures that value independence are more likely to describe themselves in terms of uniqueness.

Social Changes in Adolescence

Define identity crisis.

    The term identity crisis refers to a period of searching and social experimentation that often leads to the development of a coherent identity or self-concept.

Define cliques.

    The term cliques refers to small groups of fewer than ten people who are close friends and who usually have similar backgrounds, interests, and attitudes.

Discuss research findings concerning the popular belief that adolescence is a time of "storm and stress".

    Cross-cultural research findings indicate that most adolescents are satisfied with their lives and comfortable with their parents.

Social Development in Adulthood

Discuss recent changes in American cultural norms that have blurred the distinction between adolescence and adulthood.

    Changes include: taking longer to complete education, waiting longer to get married and have children, some individuals choosing to remain single and childless, more women working outside the home and men staying home to care for children, and older children returning to live with parents.

Discuss fluctuations in marriage satisfaction over time.

    Couples are generally happiest early and later in marriage, with lower satisfaction around 10 years into marriage. Other periods of reduced satisfaction include the early childrearing years and when children are entering adolescence.

Discuss current factors for divorce in contrast to factors for divorce in the 1940s.

    In the 1940s, the factors reported to influence divorce were behavioral, such as failure to provide financial support, alcoholism, and abuse. Currently, divorcees report simple incompatibility, lack of communication, and general unhappiness as primary reasons for divorce.

Define mid-life crisis.

    The term mid-life crisis refers to a period during which middle-aged adults are supposedly prone to depression and anxiety about the future, and undergo personality changes to some degree.

Discuss the research findings about mid-life crisis.

    Researchers have found that mid-life crisis is not generally an inevitable consequence of adult development. Actually, personality traits remain remarkably stable during adulthood.


Discuss the rationale behind Erikson's eight-stage model of psychosocial development.

    According to Erik Erikson, development progresses through eight stages across the entire life span. Each stage is marked by a crisis that can either be resolved successfully or left unresolved. If the individual succeeds at resolving a crisis at a lower level, development can occur normally at later stages. If, however, the individual fails to resolve a crisis at an earlier period of development, psychological growth is threatened.

Trust vs. Mistrust

Discuss the first stage of psychosocial development, Trust vs. Mistrust.

    The first stage, Trust vs. Mistrust, involves the first year of life, a year in which the child is completely dependent on adults for care. The positive outcome of this stage is a sense of trust of oneself and others. The negative outcome is mistrust of oneself and others. The goal of this stage is hope.

Autonomy vs. Doubt

Discuss the second stage of psychosocial development, Autonomy vs. Doubt.

    The second stage of Erikson's developmental stages involves the years of initial mobility (ages 1 to 3). Because the infant/toddler is apt to use this newfound mobility to explore the environment, it begins to test limits. If parents refuse the child's autonomy, the negative outcome is a sense of doubt, even shame. If, however, the parents allow appropriate expression of autonomy, the child is likely to achieve a healthy sense of autonomy. The goal of this stage is determination.

Initiative vs. Guilt

Discuss the third stage of psychosocial development, Initiative vs. Guilt.

    The third stage of development, from ages 3 to 6, involves the years of language development and curiosity. Children ask parents a lot of questions. If parents punish a child's inquisitiveness, the child may form a sense of guilt. If, however, the child's curiosity is allowed appropriate expression, the child will have initiative to achieve future endeavors. The goal of this stage is purpose.

Industry vs. Inferiority

Discuss the fourth stage of psychosocial development, Industry vs. Inferiority.

    The fourth stage of psychosocial development involves the school years prior to adolescence (ages 6 to adolescence). In this stage the child learns the skills necessary to attain culturally appropriate adult functioning. If the child's industry is not reinforced, the child is likely to feel inferior. If, however, industry is rewarded, the child is likely to feel industrious. The goal of this stage is competence.

Identity vs. Role Confusion

Discuss the fifth stage of psychosocial development, Identity vs. Role Confusion.

    This stage encompasses adolescence. Adolescents seek to differentiate themselves from parents and peers, and form a unique sense of identity. If they fail to form a unique identity, adolescents are likely to experience role confusion, life without meaning. The goal of this stage is identity.

Intimacy vs. Isolation

Discuss the sixth stage of psychosocial development, Intimacy vs. Isolation.

    This stage involves the young adult searching for a partner in life. If successful, the young adult achieves intimacy. If, however, the young adult fails, the result is loneliness and isolation. The goal of this stage is commitment.

Generativity vs. Stagnation

Discuss the seventh stage of psychosocial development, Generativity vs. Stagnation.

    This stage involves the adult nurturing the development of younger generations, including having children or mentoring. If successful, the adult will feel generative. If, however ,the adult fails, the negative outcome is stagnation in selfishness. The goal of this stage is caring.

Integrity vs. Despair

Discuss the eighth and final stage of psychosocial development, Integrity vs. Despair.

    This is the final stage of psychosocial development, taking place in late adulthood. The older adult reflects on a lifetime of achievements and failures, and concludes with either a sense of integrity or despair and a desire to make amends for past failures. The goal of this stage is wisdom.

Erikson's Theory in Review

Discuss researchers' agreement and disagreement with Erikson's psychosocial model of development.

    Most researchers now agree that development encompasses the life span. There is also agreement that development involves a gradual unfolding of capabilities, as well as pressure from parents, peers, and society. There is less agreement that everyone progresses through Erikson's stages at the same rate and in the same order.