Introduction to Psychology: Nature, Scope, Schools and Methods
What psychology is
Psychology is the scientific study of behaviour and mental processes. Candidates must distinguish it from pseudo-psychology and from related fields: it is empirical, uses systematic observation, and tests falsifiable claims. Know the major schools and their defining commitments: structuralism (Wundt and Titchener; introspection and elements of consciousness), functionalism (James; adaptive purpose of mind), behaviourism (Watson and Skinner; observable behaviour, learning), Gestalt (whole-configuration perception), psychoanalysis (Freud; unconscious conflict), humanistic (Maslow, Rogers; growth and self-actualisation), and cognitive (information processing).
Scope and methods
Scope spans biological, cognitive, developmental, social, personality, and abnormal areas. Methods include experimental (manipulation, control, causal inference), correlational (prediction only), naturalistic observation, case study, survey, and interview. Know the difference between independent and dependent variables, control and experimental groups, random assignment versus random sampling, and the threats to validity: confounding, demand characteristics, experimenter bias, and sampling bias. Ethics (informed consent, confidentiality, debriefing, protection from harm) are frequently tested.
Traps
A recurring trap is confusing correlation with causation, or claiming a correlational design establishes cause. Another is conflating random sampling (who is selected) with random assignment (who goes into which condition). Students also confuse introspection (structuralism) with the psychoanalytic method. Watch for questions that attribute a school to the wrong founder.
Worked example
A researcher tests whether sleep deprivation lowers test scores. Sleep condition is the IV, test score the DV. If participants choose their own sleep condition, the design is correlational and confounded; the rule of thumb is: manipulation plus control plus random assignment equals causal claim, otherwise describe association only.