Volume 4 -- Physical development: Environment versus genetics -- Physical rehabilitation -- Piaget, Jean -- Pinel, Philippe -- Pituitary gland -- Placebo effect -- Play therapy -- Pornography addiction -- Positive psychology -- Postpartum depression -- Post-traumatic stress (PTS) -- Power -- Prejudice -- Prejudice and stereotyping -- Prejudice reduction -- Prenatal physical development -- Problem-solving stages -- Problem-solving strategies -- Procrastination -- Profiling -- Projection -- Psychoanalysis -- Psychoanalytic psychology -- Psychoanalytic psychology and personality: Sigmund Freud -- Psychobiology -- Psychogenic non-epileptic seizures (PNES) -- Psychological safety -- Psychologically healthy workplace -- Psychology and film -- Psychology: Definition -- Psychology: Fields of specialization -- Psychology: History -- Psychology of social media -- Psycho-oncology -- Psychopathology -- Psychopharmacology -- Psychosexual development -- Psychosomatic disorders -- Psychosurgery -- Psychotherapy: Children -- Psychotherapy: Effectiveness -- Psychotherapy: Goals and techniques -- Psychotherapy: Historical approaches -- Psychotic disorders -- Punishment -- Qualitative research -- Quality of life -- Quasi-experimental designs -- Race and intelligence -- Racism -- Radical behaviorism: B. F. Skinner -- Rape -- Rape and sexual assault -- Rational emotive therapy -- Reactive attachment disorder (RAD) -- Reality therapy -- Reality TV -- Recency effects -- Reflexes -- Reflexes in newborns -- Reinforcement -- Relaxation response: Herbert Benson -- Religion and psychology -- Religiosity -- Repressed memories -- Research ethics -- Reticular formation -- Retirement -- Risk assessments -- Road rage -- Rogers, Carl R.

Romantic addiction -- Rorschach, Hermann -- Rorschach inkblots -- Rosenhan experiment -- Rule-governed behavior -- S-R theory: Neal E. Miller and John Dollard -- Sadism and masochism -- Sampling -- Satir, Virginia -- Schizoid personality disorder (SPD) -- Schizophrenia: Background, types, and symptoms -- Schizophrenia: High-risk children -- Schizophrenia: Theoretical explanations -- Schizotypal personality disorder -- School psychology -- Scientific methods -- Seasonal affective disorder -- Self -- Self-actualization -- Self-disclosure -- Self-efficacy -- Self-esteem -- Self-help groups -- Self-perception theory (SPT) -- Self-presentation -- Seligman, Martin E. P. -- Selye, Hans -- Sensation and perception -- Senses -- Separation and divorce: Adult issues -- Separation and divorce: Children's issues -- Separation anxiety -- Sex addiction -- Sex hormones and motivation -- Sexism -- Sexual abuse: Impact -- Sexual behavior patterns -- Sexual dysfunction -- Sexual harassment: Psychological causes and effects -- Sexual orientation -- Sexual predatory behaviors -- Sexual variants and paraphilias -- Shift work -- Shock therapy -- Short-term memory -- Shyness -- Sibling relationships -- Signal detection theory -- Sixth sense -- Skinner, B. F. -- Skinner box -- Sleep -- Sleep apnea -- Sleep disorders -- Sleep hygiene -- Smell and taste -- Social identity theory.