The Science of Psychology (Chapter Preview)

Definition: The scientific study of behavior and mental processes using systematic methods.
Distinction: Behavior is observable; mental processes are private (thoughts, feelings, motives).

Core values: $1$ Critical thinking – deep thinking and evaluation; $2$ Curiosity – asking questions; $3$ Skepticism – need evidence; $4$ Objectivity – neutrality.
Purpose: Use empirical evidence to validate beliefs about behavior and mental processes.

Example: Dinner planning shows evaluating options, nutrition, time, and practicality.

Steps: $1$ Observe, $2$ Hypothesize, $3$ Test, $4$ Conclusions, $5$ Evaluate.
Observation: phenomenon; Variable: anything that can change; Theory: broad idea to explain observations; must be falsifiable.
Hypothesis: a testable prediction derived from a theory; multiple hypotheses can come from a theory.
Testing: use operational definitions; collect and analyze data with statistics.
Conclusions: replication and reliability.
Evaluation: assess the theory; peer review and publication; science is iterative.
Validity notes: External validity = generalizability to the real world; Internal validity = whether changes in the DV are due to the IV (bias, confounds).

Variable: anything that can change.
Theory: broad explanation for observations; must be falsifiable to be scientific.

Hypothesis: testable prediction derived from a theory; allows empirical testing.
Example: Individuals who spend more time in natural environments will report higher mood and well-being.

Descriptive: goal is to describe a phenomenon using Observation, Surveys, Interviews, Case studies.
Correlational: goal is to identify relationships between variables; correlation does not imply causation.
Experimental: goal is to establish cause-and-effect by manipulating an independent variable under controlled conditions; use random assignment; includes experimental and control groups; replication is crucial.

External Validity: generalizability to real-world settings.
Internal Validity: proper manipulation of the IV, control of confounds.
Participant bias: participants’ expectations; Experimenter bias: experimenter’s expectations; Placebo effect.
Double-blind: neither participants nor researchers know who is in which group.
Ethics (APA): Informed consent; Confidentiality; Debriefing; Deception considered carefully; no harm to participants.

Behavioral Neuroscience; Sensation & Perception; Learning; Cognitive; Developmental; Motivation & Emotion; Personality; Social; Clinical & Counseling; Health; Industrial/Organizational; Community; School & Educational; Environmental; Psychology of Women; Forensic; Sport; Cross-Cultural.

Wilhelm Wundt: founded first psychology lab in Germany; father of psychology; Structuralism; introspection.
William James: Functionalism; focus on purposes of mind; Darwinian influence; natural selection.

Biological; Behavioral; Psychodynamic; Humanistic; Cognitive; Evolutionary; Sociocultural.
Biopsychosocial approach: biological, psychological, and social factors all contribute to behavior.

Avoid overgeneralizing; seek converging evidence; be cautious with causal inferences; consider sources.

Animal research benefits humans; used by ~ $5$ % of researchers; rats/mice ~ $90$ %; welfare standards include housing, feeding, well-being.