1.1 Theories and Perspectives in Developmental Psychology

Psychodynamic and Behavioral Theories

Developmental psychology explores how people change across the entire lifespan. The theories in this unit each offer a different lens for understanding that change, and you'll need to know what each one emphasizes, who developed it, and how it explains growth differently from the others.

Psychoanalytic Theory

Psychoanalytic theory, founded by Sigmund Freud, argues that unconscious thoughts, feelings, and early experiences are the primary forces shaping personality and behavior. Much of what drives us, according to Freud, operates below our conscious awareness.

Freud proposed that the mind has three interacting parts:

• Id — operates on the pleasure principle; it's the source of primitive, instinctual drives and wants immediate gratification
• Ego — operates on the reality principle; it mediates between the id's demands and the constraints of the real world
• Superego — represents internalized moral standards and conscience, pushing the individual toward idealistic behavior

Freud also proposed that development unfolds through five psychosexual stages: oral, anal, phallic, latency, and genital. Each stage centers on a different body area as the source of pleasure. If a child's needs aren't properly met at a given stage, Freud argued they could develop a fixation, leading to specific personality traits later in life.

To manage anxiety from conflicts between the id, ego, and superego, the ego uses defense mechanisms like repression (pushing threatening thoughts out of awareness) and projection (attributing your own unacceptable feelings to someone else).

Behaviorism

Behaviorism takes the opposite approach from psychoanalytic theory. Instead of focusing on internal, unconscious processes, it focuses strictly on observable behavior and the environmental factors that shape it. The core idea is that nearly all behavior is learned.

Two major learning processes fall under this umbrella:

• Classical conditioning, discovered by Ivan Pavlov, involves learning to associate a neutral stimulus with one that naturally triggers a response. In Pavlov's famous experiment, dogs learned to salivate at the sound of a bell because the bell had been repeatedly paired with food.
• Operant conditioning, developed by B.F. Skinner, involves learning through consequences. Reinforcement (rewards) increases the likelihood of a behavior, while punishment decreases it. For example, a child who receives praise for sharing is more likely to share again.

John B. Watson was a founding figure in behaviorism who argued that psychology should study only what can be directly observed and measured, rejecting the study of internal mental states.

Social Learning Theory

Albert Bandura's social learning theory bridges behaviorism and cognitive psychology. It keeps the behaviorist emphasis on learning from the environment but adds a critical ingredient: people also learn by watching others.

This is called observational learning (or modeling). Bandura's famous Bobo doll experiment showed that children who watched an adult act aggressively toward a doll were more likely to imitate that aggression themselves.

Two key concepts to know:

• Vicarious reinforcement — You don't have to experience a reward or punishment yourself. If you see someone else get rewarded for a behavior, you're more likely to try it. If you see them get punished, you're less likely.
• Self-efficacy — This is your belief in your own ability to succeed at a specific task. Bandura argued that self-efficacy strongly influences whether you'll even attempt a challenging behavior and how much effort you'll put in.

Cognitive and Information Processing Theories

Cognitive-Developmental Theory

Cognitive-developmental theory focuses on how mental processes like thinking, reasoning, and problem-solving change as people grow. The two major theorists here are Piaget and Vygotsky, and they emphasize very different things.

Jean Piaget proposed that children move through four stages of cognitive development in a fixed order:

1. Sensorimotor (birth to ~2 years) — Infants learn through senses and motor actions. A major milestone is developing object permanence, the understanding that objects continue to exist even when out of sight.
2. Preoperational (~2 to 7 years) — Children begin using symbols and language but struggle with logic. They tend to be egocentric, meaning they have difficulty seeing things from another person's perspective.
3. Concrete operational (~7 to 11 years) — Logical thinking develops, but it's tied to concrete, tangible situations. Children master conservation, understanding that quantity doesn't change just because appearance does.
4. Formal operational (~11 years and older) — Abstract and hypothetical thinking becomes possible. Adolescents can reason about "what if" scenarios.

Piaget saw children as active learners who construct their understanding of the world through two processes: assimilation (fitting new information into existing mental frameworks, or schemas) and accommodation (adjusting existing schemas when new information doesn't fit).

Lev Vygotsky emphasized that cognitive development is fundamentally social. He introduced the zone of proximal development (ZPD), which is the gap between what a learner can do independently and what they can do with guidance from a more skilled person. Scaffolding refers to the support provided within that zone, which is gradually removed as the learner gains competence.

Information Processing Theory

Information processing theory compares the human mind to a computer. Rather than proposing stages of development, it examines how people take in, organize, store, and retrieve information, and how these abilities improve with age.

The model identifies three memory stores:

• Sensory memory — Holds incoming sensory information for a very brief time (fractions of a second to a few seconds)
• Short-term (working) memory — Actively holds and manipulates a small amount of information; limited in both capacity and duration
• Long-term memory — Stores information more permanently, with a much larger capacity

Attention is a limited resource that determines which information gets processed further. This is why young children, whose attentional control is still developing, often struggle with tasks that require sustained focus.

Two strategies that improve memory and learning:

• Chunking — Grouping individual pieces of information into larger, meaningful units (e.g., remembering a phone number as three chunks rather than ten separate digits)
• Elaborative rehearsal — Connecting new information to things you already know, which creates deeper encoding than simple repetition

Contextual and Evolutionary Theories

Ecological Systems Theory

Urie Bronfenbrenner's ecological systems theory shifts the focus away from the individual alone and toward the multiple environments that surround and influence development. The central idea is that development happens within a set of nested systems, each affecting the others.

The five systems, from closest to most distant:

• Microsystem — The immediate settings where the person directly interacts (family, school, peer group)
• Mesosystem — The connections between microsystems (e.g., how a parent's relationship with a teacher affects the child's school experience)
• Exosystem — Settings the person doesn't directly participate in but that still affect them (e.g., a parent's workplace policies influencing family time)
• Macrosystem — The broader cultural values, laws, and customs that shape all the other systems
• Chronosystem — Changes over time, both in the person's life and in the historical period (e.g., growing up during a pandemic vs. a period of stability)

Bronfenbrenner later expanded this into the bioecological model, which highlights proximal processes as the primary engine of development. These are the regular, sustained interactions between a person and their immediate environment, like a parent reading to a child every night.

Sociocultural Theory

Sociocultural theory, primarily associated with Lev Vygotsky, argues that cognitive development is rooted in social interaction and cultural context. Higher mental functions (like logical reasoning and voluntary attention) first appear in interactions between people and are then internalized by the individual.

The zone of proximal development and scaffolding are central here as well (see Cognitive-Developmental Theory above). What sociocultural theory adds beyond Piaget's framework is a strong emphasis on cultural tools, the language, symbols, number systems, and artifacts that a culture provides. These tools don't just help thinking; they fundamentally shape how people think. A child growing up with an abacus develops different mathematical reasoning strategies than one growing up with a calculator.

Evolutionary Developmental Psychology

Evolutionary developmental psychology combines evolutionary theory with developmental science. It asks: how have natural selection and environmental pressures shaped the way humans develop?

The core premise is that many developmental processes exist because they provided survival or reproductive advantages over evolutionary time. But this doesn't mean development is rigidly programmed. A key concept is evolved developmental plasticity, the idea that humans have evolved the capacity to adjust their developmental trajectory based on environmental cues, especially during sensitive periods when the organism is particularly responsive to certain types of input.

Life history theory examines how organisms allocate limited resources across competing demands: growth, reproduction, and survival. Environmental conditions push individuals toward different strategies:

• Fast life history strategy — In harsh, unpredictable environments, organisms tend toward earlier puberty, earlier reproduction, and greater number of offspring with less investment in each
• Slow life history strategy — In stable, resource-rich environments, organisms tend toward later maturation, fewer offspring, and greater parental investment in each

This framework helps explain why children growing up in high-stress environments sometimes show accelerated physical maturation compared to peers in more stable settings.