Unit 3: Development and Learning

Introduction to Developmental Psychology

• Life's Journey: Often described as a journey from ‘Womb to Tomb,’ our lives are constantly influenced by the interplay between Nature (genetics) and Nurture (environment/experience).

• Core Focus of Developmental Psychology: This field studies physical, cognitive, and social change throughout the entire human life span. It focuses on three major ideas:     * Nature and Nurture: We are formed by the interaction of genetics and a lifetime of experiences. While we share common traits (e.g., all babies babble), specific experiences, such as having supportive parents, lead to different outcomes (e.g., being less hostile as adults). Nurture works on what Nature endows.     * Continuity and Stages: Researchers debate whether development is gradual and continuous—like riding an escalator—or occurs in abrupt, genetically predisposed stages—like climbing rungs on a ladder. Those favoring experience/learning emphasize continuity; those favoring biological maturation emphasize stages (e.g., Piaget, Kohlberg, Erickson).     * Stability and Change: This involves determining which traits remain constant throughout life and which change as we grow older.

• Biopsychosocial Forces: Human development is an interaction of biological, psychological, and social-cultural forces. Regardless of specific culture, all humans share the same basic life cycle.

Prenatal Development and the Newborn

• Conception and the Science of Life:     * Women are born with all the eggs they will ever need, whereas men do not begin producing sperm until puberty.     * Fewer than half of all fertilized eggs survive beyond the first few weeks.

• The Zygote ($0-2$ weeks):     * The fertilized egg is known as a ‘zygote.’     * It enters a $2$-week period of rapid cell division.     * Approximately $1$ in $270$ zygotes will split, resulting in identical twins.     * At roughly $10$ days post-conception (the germinal stage), the zygote attaches to the uterine wall.     * The inner cells become the ‘embryo,’ and the outer cells become the ‘placenta.’

• The Embryo ($2-9$ weeks):     * Over the next $6$ weeks, organs begin to form and function.     * The heart begins to beat during this stage.

• The Fetus ($9$ weeks to birth):     * After $9$ weeks, the embryo looks human and is called a ‘fetus.’     * By the $6^{th}$ month, the stomach has formed, providing a premature baby a chance at survival.     * Environmental factors include bonding with the mother’s voice and language(s).

• Environmental Hazards (Teratogens):     * Teratogens are agents such as chemicals and viruses that can reach the fetus and cause damage.     * Alcohol and Drugs: These trigger ‘epigenetic’ effects.     * Fetal Alcohol Syndrome (FAS): Characterized by physical and cognitive abnormalities, including abnormal head and facial features, caused by heavy drinking during pregnancy.

• Newborn Competencies:     * Infants are born with automatic reflex responses for survival:         * Rooting Reflex: A baby instinctively sucks when something touches their cheek (searching for a nipple). This involves a complex coordination of tonguing, swallowing, and breathing.         * Crying: An evolutionary signal for help. Parents respond to stop the noise (an example of Negative Reinforcement).         * Startle and Grasping Reflexes.     * Habituation: A decrease in responsiveness with repeated stimulation. Babies prefer new, interesting images over old ones and are preloaded to respond to faces and their mother’s scent.

Physical and Motor Development

• Maturation:     * Defined as biological growth processes that enable orderly changes in behavior, relatively uninfluenced by experience.     * Genetic growth tendencies are inborn (e.g., standing before walking, using nouns before adjectives).     * While you cannot speed up this ‘factory-installed rate,’ neglect or severe deprivation can slow it down.

• Brain Development:     * Humans are born with most of the brain cells they will ever have.     * Birth to $3$ years: Massive growth in neural networks enabling walking, talking, and remembering.     * $3$ to $6$ years: Intense growth in the frontal lobes, allowing for rational planning and control of attention/behavior.     * Association Areas: Thinking, memory, and language areas are the last to develop.     * Pruning Process: A ‘use it or lose it’ scenario where unused pathways shut down and well-used ones (strengthened by study, music, sports, etc.) are reinforced.     * Critical Periods: Optimal periods early in life when exposure to certain stimuli (like language or movement) is required for normal development.     * Rosenzweig and Krech Study: Rat studies demonstrated that ‘enriched’ environments lead to significantly more neural connections than ‘impoverished’ environments.

• Motor Development:     * The sequence of motor milestones is universal (crawling, walking, bladder control) and depends on the maturation of the nervous system.     * ‘Back to Sleep’ Position: Putting babies to sleep on their backs reduces smothering hazards but has been associated with slightly later crawling (though it does not affect the timing of walking).

Adolescence and Adulthood

• Adolescence: The transitional period between childhood and adulthood ($RIGHT\,NOW$ for students), starting with puberty.     * Puberty: Physical and sexual development.     * Menarche (First Period): Can occur as early as $9$ years old; average timing around $12.5$.     * Spermarche (First Ejaculation): Can occur as late as $16$ years old; average timing around $14$.

• Adulthood and Aging:     * Physical abilities (muscle strength, reaction time, flexibility) begin to decline in the mid-$20s$.     * Menopause: Occurs around age $50$, ending a woman’s ability to reproduce.     * Health in Late Life: The immune system weakens, increasing vulnerability to cancer and pneumonia. Chronically active adults remain mentally sharper than sedentary ones.     * Death Deferral: Evidence suggests people may pass away shortly after reaching significant milestones, like holidays.     * Social Clock: The culturally preferred timing of social events (marriage, parenthood, retirement).

Gender, Sex, and Sexual Orientation

• Key Definitions:     * Sex: Biologically influenced characteristics (defined by the ‘body’).     * Gender: Attitudes, feelings, and behaviors associated with a biological sex (defined by the ‘mind’).     * Intersex: Individuals born with elements of both male and female reproductive organs.

• Biological Determination of Sex:     * Humans have $46$ chromosomes ($23$ from each parent). $45$ are unisex.     * The $46^{th}$ chromosome determines sex: $X$ from mother + $X$ from father = Female; $X$ from mother + $Y$ from father = Male.     * The $Y$ chromosome triggers the production of Testosterone.

• Sexual Development during Puberty:     * Primary Sexual Characteristics: Reproductive organs (testes, ovaries, external genitalia).     * Secondary Sexual Characteristics: Non-reproductive traits (breasts, hips, deeper voices, body hair).

• Psychology of Gender:     * Gender Roles: Socially expected behaviors/traits for men and women.     * Gender Identity: A personal sense of being male or female.     * Social Learning Theory: We learn gender behavior by observing, imitating, and being rewarded or punished.     * Gender Typing: The acquisition of traditional masculine or feminine roles.     * Androgyny: Blending both male and female behavioral characteristics.     * Transgender: When identity differs from birth sex.

• Sexual Orientation:     * The enduring attraction toward the same, opposite, or both sexes. Roughly $3\%$ of men and $1-2\%$ of women are gay/lesbian.     * Biological Correlates: Smaller cell cluster in the gay male hypothalamus; gay male hypothalamus responds like a straight female's to male hormones; family heredity/twin studies indicate genetic influence; older-brother effect (prenatal immune response).     * Note: The APA classified homosexuality as a disorder until $1973$.

Cognitive Development: Piaget and Vygotsky

• Jean Piaget’s Theory: The mind develops through specific stages driven by a desire to make sense of experiences.     * Schemas: Frameworks that organize and interpret information.     * Assimilation: Interpreting new experiences in terms of existing schemas.     * Accommodation: Adapting schemas to incorporate new information.

• Piaget’s Four Stages:     1. Sensorimotor (Birth to $2$): Learning through senses/actions. Key concept: Object Permanence (knowing things exist even when out of sight). Babies also show ‘Baby Physics’ and ‘Baby Math’ skills.     2. Preoperational ($2$ to $6/7$): Symbolic thinking, language growth. Characteristics: Egocentrism (difficulty taking another's perspective), lack of Conservation (understanding that quantity remains the same despite change in shape), and Animism.     3. Concrete Operational ($6/7$ to $12$): Logical thinking about concrete events and mathematical transformations.     4. Formal Operational ($12+$): Abstract thinking and hypothetical logic (‘If-then’ reasoning).

• Lev Vygotsky’s Perspective: Focused on social development.     * Scaffolding: Children build new skills upon basic ones with the help of mentors.     * Inner Speech: Children talk to themselves to solve problems and control behavior.     * Zone of Proximal Development: The gap between what a child can do alone and what they can do with help (e.g., training wheels).

Moral Development

• Lawrence Kohlberg’s Moral Stages:     * Preconventional (Before age $9$): Morality is based on self-interest; obey to avoid punishment or gain rewards.     * Conventional (Adolescence/Adults): Morality is based on upholding laws and social rules to gain social approval or maintain order.     * Postconventional ($0-15\%$ of those over $20$): Morality is based on self-defined ethical principles and universal justice.

• Moral Intuition (Jonathan Haidt): Belief that morality is rooted in spontaneous ‘gut feelings’ and aesthetic judgments (disgust vs. joy).

• Carol Gilligan's Critique: Argued Kohlberg’s theory was male-centered and neglected ‘moral feelings’ and caring sentiments.

Thinking and Language

• Language Building Blocks:     * Phoneme: The smallest distinctive sound unit ($D\,O\,G$; $CH\,A\,T$). Consonants carry more information than vowels.     * Morpheme: The smallest unit carrying meaning (e.g., ‘pre’ in preview, or the word ‘bat’).     * Grammar: System of rules. Includes Semantics (deriving meaning) and Syntax (ordering words into sentences).

• Universal Grammar (Noam Chomsky): Humans have an innate predisposition to learn language. All humans share the same underlying building blocks of grammar.

• Language Milestones:     * Receptive Language: Ability to understand what is said to you.     * Productive Language ($4$ months+): Ability to produce words.     * Telegraphic Speech ($2$ years): Simple noun-verb combinations (e.g., ‘Get car’).

• The Brain and Aphasia:     * Aphasia: Communication disorder from brain damage (usually left hemisphere).     * Broca’s Area (Frontal Lobe): Responsible for speech production. Damage leads to inability to form words.     * Wernicke’s Area (Temporal Lobe): Responsible for language comprehension. Damage leads to speaking ‘nonsense’ words.

• Linguistic Determinism (Whorf): The hypothesis that language determines how we think. Modern view is Linguistic Relativism: language influences rather than determines thought.

Social Development: Attachment

• Origins of Attachment:     * Stranger Anxiety: Develops around $8$ months.     * Harry Harlow’s Monkey Research: Demonstrated that attachment is based on Body Contact (comfort) rather than just providing nourishment.     * Mary Ainsworth’s Strange Situation:         * Secure Attachment: Child explores happily in mother’s presence, is distressed when she leaves, and seeks her when she returns.         * Insecure Attachment: Child clings to mother, is less likely to explore, and may cry loudly when she leaves or remain indifferent upon her return.

• Temperament: A person’s characteristic emotional reactivity (nature). It tends to be stable over time.

• Familiarity:     * Imprinting (Konrad Lorenz): Process by which certain animals (ducks/geese) form rigid attachments during a critical period early in life. Humans do not imprint but do become attached via repeated exposure.

• Self-Concept: Our answer to ‘Who am I?’ Usually developed by age $12$. Tested via the Mirror Test; children recognize themselves around $18$ months.

• Parenting Styles (Diana Baumrind):     * Authoritarian: Dictatorial; imposes strict rules and expects obedience.     * Permissive: Few demands, little punishment.     * Authoritative: Demanding but responsive; sets rules but explains reasons and encourages discussion.     * Neglectful: Uninvolved.

Introduction to Learning and Classical Conditioning

• Learning: The process of acquiring new and relatively enduring information or behaviors.

• Associative Learning: Learning that certain events occur together (Classical or Operant).

• Classical Conditioning (Ivan Pavlov): Linking two stimuli to anticipate events.     * Neutral Stimulus (NS): A stimulus that elicits no response before conditioning.     * Unconditioned Stimulus (UCS) & Unconditioned Response (UCR): A natural relationship (e.g., food causing salivation).     * Conditioned Stimulus (CS) & Conditioned Response (CR): The learned relationship (e.g., a bell causing salivation).

• Principles of Classical Conditioning:     * Acquisition: The initial stage of linking the NS and UCS ($0.5$ seconds is optimal).     * Higher Order Conditioning: Pairing a new NS with an existing CS (usually results in a weaker CR).     * Extinction: The diminishing of a CR when the UCS no longer follows the CS.     * Spontaneous Recovery: Reappearance of an extinguished CR after a pause.     * Generalization: Tendency to respond to stimuli similar to the CS.     * Discrimination: Learned ability to distinguish between a CS and irrelevant stimuli.

• Biological Limits (John Garcia): Creatures are biologically predisposed to learn associations that help them survive (e.g., Taste Aversion in rats happens even if sickness occurs hours later).

Operant Conditioning

• B.F. Skinner: Expanded on Thorndike’s Law of Effect (rewarded behavior is likely to recur).

• Reinforcement (Increases Behavior):     * Positive Reinforcement: Adding a desirable stimulus (e.g., a treat).     * Negative Reinforcement: Removing an aversive stimulus (e.g., taking aspirin to stop a headache, fanning oneself to escape heat, putting on a seatbelt to stop a buzzer).

• Punishment (Decreases Behavior):     * Positive Punishment: Administering an aversive stimulus (e.g., a spray of water).     * Negative Punishment: Withdrawing a rewarding stimulus (e.g., revoking a driver’s license).

• Schedules of Reinforcement:     * Fixed Ratio: Reinforce after a set number of responses.     * Variable Ratio: Reinforce after an unpredictable number of responses (highest response rate).     * Fixed Interval: Reinforce after a set time period.     * Variable Interval: Reinforce after unpredictable time intervals.

• Shaping: Using reinforcers to guide behavior toward closer and closer approximations of a desired goal.

• Instinctive Drift: The tendency for trained animals to revert to their natural, biological predispositions despite conditioning (e.g., pigs rooting instead of carrying coins).

Cognition and Observational Learning

• Cognitive Map (Edward Tolman): A mental representation of the layout of one’s environment.

• Latent Learning: Learning that occurs but is not apparent until there is an incentive to demonstrate it.

• Insight: A sudden realization of a problem's solution.

• Observational Learning (Albert Bandura): Learning by watching others. Also called Social Learning.     * Modeling: Observing and imitating specific behaviors.     * Vicarious Reinforcement/Punishment: Learning outcomes by watching others experience them.     * Mirror Neurons: Frontal lobe neurons that fire when performing actions or observing someone else do so. These are the basis for empathy and imitation.     * Bobo Doll Experiment: Children imitated the aggressive behavior adults showed toward an inflatable doll.

• Prosocial vs. Antisocial Behavior: Modeling can lead to positive, helpful (prosocial) actions or negative, destructive (antisocial) actions.