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Week 11 · Lecture outline

Week 11 — Lecture Outline · Development Across the Lifespan

Introduction to Psychology · PSYC 1 Fall 2026 · Prof. Bennett Fictional sample

Course: Introduction to Psychology (PSYC 1) · Silver Oak University (fictional sample) · Prof. Bennett
Objectives covered: Objective 7 — Describe physical, cognitive, and social development across the lifespan and compare the major theories of personality (this week: the lifespan-development half).
SLOs touched: A (apply concepts to real-world behavior) · B (reason scientifically about claims regarding mind and behavior)
Meeting pattern: 2 sessions × 75 min = 150 min. Segment minutes below total ~150; scale to your own pattern.

Week at a Glance
The week's big question "How do we grow — in body, mind, and relationships — from a newborn to old age, and is that growth one smooth ramp or a series of stages?"
By the end of the week, students can… (1) state the three big questions of developmental psychology — nature & nurture (interaction), continuity vs. stages, stability vs. change; (2) name and order Piaget's four stages (sensorimotor, preoperational, concrete operational, formal operational) and recognize each from a child's behavior; (3) explain attachment through Harlow (contact comfort) and Ainsworth's Strange Situation (secure vs. insecure); (4) trace Erikson's psychosocial stages across the lifespan and apply 2–3 well; (5) describe key shifts of adolescence (identity) and aging (fluid vs. crystallized intelligence).
Key vocabulary developmental psychology, nature & nurture, continuity vs. stages, stability vs. change, maturation, Piaget, schema, assimilation, accommodation, sensorimotor, object permanence, preoperational, egocentrism, conservation, concrete operational, formal operational, Vygotsky, zone of proximal development (ZPD), scaffolding, attachment, Harlow, contact comfort, Ainsworth, Strange Situation, secure/insecure attachment, parenting styles, Erikson, psychosocial stages, trust vs. mistrust, identity vs. role confusion, integrity vs. despair, adolescence, fluid intelligence, crystallized intelligence
Materials slides (Deck 11), the week's readings + video links, one approved chatbot (Gemini / Claude / ChatGPT) for the AI-critique moment and the tutorial
Timing note 8 segments, ~150 min total. Session 1 = Segments 1–4 (~75). Session 2 = Segments 5–8 (~75).

Segment 1 — Hook & the Promise (8 min) · Session 1 opens

Hook. Put one image-prompt on a slide and ask the room to answer out loud, fast: "A 4-year-old watches you pour the SAME juice from a short, fat cup into a tall, skinny one. You ask: 'Did the amount change?' What does the 4-year-old say — and what does a 9-year-old say?" Let them call it out. Most rooms guess that the little one says "more now!" and the older one says "same." Then: "You just predicted something deep about how a child's mind is built — and by Friday you'll know the name for it (conservation), the stage it belongs to, and why it's not about being 'smart' but about the mind literally growing new abilities."

The promise (write it on the board): "By Friday you'll be able to take any age — a baby, a toddler, a teenager, your grandparent — and say what's happening in their body, their thinking, and their relationships, using the names psychologists give those changes."

Why it matters line (memory hook): "Development isn't a thing that ends at 18 — it's the one project that runs the whole length of your life."

Segment 2 — What Developmental Psychology Studies + the Three Big Questions (20 min)

Plain language first.
- Developmental psychology is the study of how we change — and stay the same — across the whole lifespan, from before birth to the end of life. It tracks three streams at once: physical (the body), cognitive (thinking and memory), and social/emotional (relationships and the self).

The field's three enduring debates (put them on a slide, one line each):
- Nature & nurture. Do genes or experience make us who we are? The modern answer is "both, interacting" — not a tug-of-war. Your height has a genetic ceiling and depends on childhood nutrition; your language is built from an inherited capacity and the specific language you heard. "It was never nature OR nurture — it's nature AND nurture, woven together."
- Continuity vs. stages. Is growth a smooth, gradual ramp (continuity) or a series of distinct steps where something genuinely new appears (stages)? Some changes look continuous (vocabulary slowly growing); others look stage-like (a child who suddenly "gets" that hidden objects still exist).
- Stability vs. change. Do our traits stay constant across life, or do we change? A shy toddler often becomes a reserved adult (stability) — yet people also grow and shift (change). The honest answer is "some of each."

Memory hook (put it on a slide):

"Three questions follow you the whole week: nature & nurture, continuity or stages, stability or change."

One quick clarification students always need:
- Newborns are NOT blank slates. A baby arrives with reflexes (rooting, sucking, grasping), preferences (for faces, for mom's voice and smell), and astonishingly fast learning. "Blank slate" is a myth we'll cure later in the hour.

Segment 3 — Cognitive Development: Piaget's Four Stages (25 min)

Plain language first. Jean Piaget watched children closely and argued that kids don't just know less than adults — they think in qualitatively different ways, and they move through four stages in a fixed order. The engine: a schema (a mental "file folder" for a concept), updated two ways — assimilation (fit new info into an old folder: a child calls a cat "doggy") and accommodation (make a new folder: "oh, that's a cat").

The four stages (put the ages + one signature feature on a slide):
- Sensorimotor (birth–~2). Babies know the world through senses and motor action — looking, grasping, mouthing. The headline achievement: object permanence — realizing that things still exist when you can't see them. (Before it develops, "out of sight" is "out of existence" — which is why peekaboo is magic to an infant.)
- Preoperational (~2–7). Big leap into language and pretend play, but thinking is still pre-logical. Two signature limits: egocentrism — difficulty taking another person's point of view (not selfishness, a perceptual limit) — and a lack of conservation — not yet grasping that quantity stays the same when only the shape/arrangement changes.
- Concrete operational (~7–11). Logic arrives — for concrete, hands-on situations. The child now conserves (knows the tall glass holds the same as the short one) and can reason about real objects, classify, and grasp reversibility.
- Formal operational (~12+). Abstract and hypothetical reasoning comes online — "what if," systematic problem-solving, reasoning about ideas and ideals, not just things in front of you.

Memory hook: "Sensorimotor → Preoperational → Concrete → Formal. Senses, then symbols, then logic about things, then logic about ideas."

Vygotsky in one minute (the social angle on thinking). Where Piaget focused on the lone child exploring, Lev Vygotsky stressed that thinking grows through social interaction. Two terms:
- Zone of proximal development (ZPD): the sweet spot — what a child can't quite do alone but can do with help.
- Scaffolding: the support a more skilled person provides in that zone, then gradually removes as the child takes over (like training wheels). "Piaget: the child is a little scientist. Vygotsky: the child is a little apprentice."

Segment 4 — The Conservation Task (worked example) + Quick Interaction (22 min) · Session 1 closes (~75)

Set it up: "Watch me run the single most famous demonstration in developmental psychology — it shows you a stage boundary live."

One fully worked example — Piaget's conservation-of-liquid task (do it out loud, step by step):

Setup: Two identical short, wide glasses, filled to the same line with juice. The child agrees: "Same amount." The move: In full view, pour ONE glass into a tall, thin glass. The juice rises higher. The question: "Now — does one have more, or are they the same?"
- A preoperational child (say, age 4–5) says the tall glass has more. Their judgment is captured by the single, salient dimension — height — and they can't yet mentally "pour it back" to see nothing was added or removed. This is the absence of conservation.
- A concrete operational child (say, age 8) says "They're the same — you just poured it, you didn't add any." They hold two dimensions at once (taller but thinner) and grasp reversibility. This is conservation.

Land it: The younger child isn't "dumb" — they are running a mind that is built differently. Nothing was added to the juice; what changed is the child's stage of reasoning. That's the whole idea of cognitive development in one cup of juice.

Misconception + cure (do it here):
- ❌ "The preoperational kid just isn't paying attention / is being silly."
✅ Cure: it's systematic, not random — nearly every child this age answers the same way, and the SAME child reliably switches to "same" a few years later. It's a developmental boundary, not a mood.

Interaction — Think-Pair-Share (rapid-fire, ~10 min):
Put four short child vignettes on a slide; students decide which Piaget stage each shows, solo (30 sec), compare with a neighbor (1 min), then vote by fingers (1 = sensorimotor … 4 = formal operational). Suggested items: "A baby is delighted when a hidden toy reappears, as if it came back from nowhere." (sensorimotor — no object permanence yet) · "A child covers her own eyes and says 'You can't see me!'" (preoperational — egocentrism) · "A 9-year-old knows a flattened ball of clay still has the same amount." (concrete operational — conservation) · "A 14-year-old debates whether a law could ever be just but still wrong." (formal operational — abstract reasoning). Debrief that the ages are approximate and the order is the real claim.

Segment 5 — Social Development: Attachment (25 min) · Session 2 opens

Hook back in: "Last session we built the thinking mind. Today: the bonding heart — how the relationship between a baby and a caregiver forms, and why it matters for a lifetime."

Plain language first — attachment is the deep emotional bond between an infant and a primary caregiver. For decades people assumed babies love whoever feeds them ("cupboard love"). Two classic lines of research overturned and refined that.

Harlow's monkeys — contact comfort beats food (the surprising study).

Harry Harlow gave infant rhesus monkeys two artificial "mothers": a bare wire mother that dispensed milk, and a soft cloth mother with no food. If attachment were really about feeding, the babies should prefer the wire feeder. Instead, they clung to the soft cloth mother nearly all day, running to her when frightened and using her as a secure base — visiting the wire mother only to feed. Lesson: attachment is built on comfort and a sense of security ("contact comfort"), not just on who provides food.

Ainsworth's Strange Situation — measuring attachment quality.

Mary Ainsworth designed a lab procedure: a baby and caregiver enter an unfamiliar room; the caregiver leaves briefly and then returns, a stranger comes and goes. What reveals the bond is the reunion — how the baby responds when the caregiver comes back. She described:
- Secure attachment (the majority): uses the caregiver as a safe base to explore, is upset at the departure, and is comforted and settles at reunion.
- Insecure attachment (avoidant or anxious/resistant): may ignore the caregiver on return, or be distressed and hard to soothe (clingy yet angry).

Secure attachment is fostered by sensitive, responsive caregiving and is associated, on average, with better social outcomes later.

Parenting styles (brief, one line each — Baumrind): authoritative (warm + firm; consistently the best outcomes), authoritarian (strict, low warmth), permissive (warm, few limits), and uninvolved/neglectful (low on both). "Warmth and structure together — that's the combination that travels best."

Memory hook: "Harlow: comfort over food. Ainsworth: it's the reunion that tells you the bond."

Segment 6 — Erikson Across the Lifespan + the Worked Stage Example (18 min)

Plain language first. Erik Erikson argued development doesn't stop at childhood — it runs the entire lifespan as a sequence of eight psychosocial stages, each posing a central "crisis," a tension to resolve. You don't have to memorize all eight cold; know the arc and a few well.

The lifespan arc (put the list on a slide; teach the starred three in depth):
- ★ Infancy — Trust vs. Mistrust: with responsive care, the baby learns the world is dependable.
- Toddler — Autonomy vs. Shame/Doubt: "I can do it myself."
- Preschool — Initiative vs. Guilt.
- School age — Industry vs. Inferiority: competence and "I can make things."
- ★ Adolescence — Identity vs. Role Confusion: the central task of the teen years — who am I? — trying on roles, values, and a sense of self.
- Young adult — Intimacy vs. Isolation: forming close bonds.
- Middle adult — Generativity vs. Stagnation: contributing, mentoring, "leaving something."
- ★ Late adulthood — Integrity vs. Despair: looking back and feeling a life was meaningful (integrity) versus regret (despair).

One fully worked example (apply a stage to a life — model the move you want by Friday):

Situation: A college first-year switches majors twice, joins and quits two clubs, and keeps asking, "But what do I actually believe?"
Erikson's read: This is Identity vs. Role Confusion in action — the adolescent/emerging-adult task. The trying-on and dropping of roles isn't flakiness; it's the healthy work of the stage — exploring options to build a coherent identity. A supportive environment that allows safe exploration helps the student emerge with a clearer sense of self. "Name the age, name the central tension — that's how you apply Erikson."

Memory hook: "Cradle to grave, one tension at a time: Trust as a baby, Identity as a teen, Integrity at the end."

Segment 7 — Adolescence, Adulthood & Aging (20 min)

Plain language first. Two life phases students most want the science on:

  • Adolescence is the bridge from childhood to adulthood. Physically it opens with puberty; cognitively, formal operational thought matures (abstract reasoning, idealism, arguing about hypotheticals); socially, the headline task is identity formation (Erikson's identity vs. role confusion). Peers grow central; risk-taking can rise as the emotional brain outpaces the still-maturing planning brain.
  • Adulthood and aging. Development keeps going. A key, hopeful finding about intelligence in aging is the split between two kinds:
  • Fluid intelligence — raw, on-the-spot reasoning and processing speed (solving a brand-new puzzle quickly). It tends to decline gradually with age.
  • Crystallized intelligence — accumulated knowledge, vocabulary, and expertise. It tends to hold steady or even grow well into late life.
    "Speed fades; wisdom compounds. The older mind trades quickness for depth."

Misconception + cure (do both here):
- ❌ "Development basically stops after childhood."
✅ Cure: Erikson runs to the last stage of life; intelligence keeps shifting (crystallized still rising); relationships, identity, and the brain keep changing. Development is lifelong.
- ❌ "Aging is just decline."
✅ Cure: some things slow (fluid intelligence, processing speed), but others strengthen (crystallized intelligence, emotional regulation, expertise). It's change, not pure loss.

Quick callback to the three big questions: aging is a clean case of stability AND change at once — a lifelong temperament can persist while abilities and priorities shift.

Segment 8 — Technology Workflow + AI-Critique, Callback & Hand-off (12 min) · Session 2 closes (~75)

Technology workflow — the "place the age" habit, on demand:
1. Pick any person by age (a niece who's 3, a friend who's 16, a grandparent who's 80).
2. Write three column headers: Body · Mind · Relationships/Self.
3. Fill one line per column using this week's names — e.g., for the 3-year-old: Body (rapid motor growth), Mind (preoperational — egocentrism, no conservation yet), Self (Erikson's initiative; autonomy just behind).
4. Notice how naming the stage turns "they're just being a kid" into a specific, testable claim.

AI-critique moment (students verify, not consume):

Paste this to an approved chatbot: "List Piaget's four stages of cognitive development in order, with the typical age range and the ONE signature achievement of each. Then define object permanence and say which stage it belongs to."
Then check its work against today's lecture. Watch for two classic model errors: mis-ordering the stages (e.g., swapping concrete and formal operational) or misplacing a hallmark (putting object permanence in preoperational instead of sensorimotor, or claiming abstract reasoning starts earlier than formal operational). Your job all semester: the tool drafts, you judge. This is exactly how the weekly Lecture Tutorial works — you catch the model, not trust it.

Callback + tease:
- Callback: "We've now followed one human across an entire life — the thinking mind (Piaget/Vygotsky), the bonding heart (Harlow/Ainsworth), and the lifelong identity project (Erikson), all riding on nature and nurture."
- Tease next week: "We kept asking who am I? through Erikson. Next week we answer it head-on — personality: the psychodynamic, humanistic, trait/Big Five, and social-cognitive theories of what makes you you."

Hand-off (the week's graded work):
- Lecture Tutorial 11 (AI tutor, share-link submission) — the three big questions, Piaget's stages, attachment, Erikson, and aging.
- Quiz 11 (end of week) and Discussion 11 ("Nature, Nurture, and Who You Became").
- Assignment 11 — identify Piaget stages from behavior, classify attachment, apply an Erikson stage, and explain how nature and nurture interact.

Instructor FAQ — Common Stumbles

Student says / does Quick cure
"Is it nature or nurture?" Neither alone — both, interacting. Genes set ranges; experience shapes where you land inside them. Reframe every "or" as an "and."
Puts object permanence in the wrong stage. It's the hallmark of the sensorimotor stage (birth–2). Hook: "Babies, peekaboo, object permanence."
Confuses egocentrism with selfishness. Egocentrism is a perceptual limit — the preoperational child literally can't take another viewpoint yet. It's about ability, not attitude.
Mixes up assimilation and accommodation. Assimilation = fit new info into an existing schema ("doggy!" at a cat). Accommodation = change/add a schema ("that's a cat").
Thinks Harlow showed babies bond to whoever feeds them. Opposite — the monkeys chose the soft cloth mother with no food over the wire feeder. Contact comfort > food.
Treats Erikson's stages as childhood-only. Erikson runs the whole lifespan — identity in adolescence, integrity in old age. Development doesn't stop.
Swaps fluid and crystallized intelligence. Fluid = fast, novel problem-solving (declines with age). Crystallized = stored knowledge/vocabulary (holds or grows). "Fluid is speed; crystallized is stuff you know."
Says development ends at adulthood. Lifelong: Erikson to the end, crystallized intelligence still rising, the brain and relationships still changing.
Reads Piaget's age ranges as exact. Ages are approximate; the fixed order of stages is the real claim. Don't grade a kid by the calendar.

Scope flag

This outline stays within the lifespan-development half of Objective 7 (developmental psychology's big questions; Piaget and a brief Vygotsky; attachment via Harlow and Ainsworth; Erikson's arc; adolescence and aging). The personality half of Objective 7 — psychodynamic, humanistic, trait/Big Five, and social-cognitive theories — is Week 12 and is only teased here. Moral-reasoning theories (e.g., Kohlberg) and the full eight Erikson stages in depth are referenced lightly, not exhaustively treated, consistent with an intro survey. The historical figures named (Piaget, Vygotsky, Harlow, Ainsworth, Erikson, Baumrind) are referenced factually as part of the discipline's real research history; the instructor and institution remain fictional.

~ Prof. Bennett's edition · Fall 2026 · built with thecoursemaker.com