Psychology as a Science and Human Diversity

Psychology as a Science

• Psychology, as a science, employs the scientific method 

• Descartes' dualism posits a separation of mind and body 

• Structuralism sought to analyze the basic elements of consciousness through introspection 

• Introspection involved self-reporting of mental experiences 

• Functionalism focused on the adaptive functions of consciousness 

• Behaviorism emphasized the role of observable behaviors and environmental influences in learning and development 

• A modern definition of psychology emphasizes behavior and mental processes 

• Levels of analysis include biological, psychological, and social-cultural factors 

• Basic research examines fundamental principles, while applied research addresses practical problems 

• Psychology subfields include clinical, counseling, cognitive, neuroscience, industrial-organizational, developmental, and social 

Nature, Nurture, and Human Diversity

• Behavior genetics studies the influence of genes on behavior 

• The nature vs. nurture debate examines the relative contributions of genetics and environment 

• Genetic determinism suggests that genes solely shape traits 

• Traits are distinguishing characteristics or qualities 

• Environment encompasses external factors, influencing development and behavior 

• Twin studies (identical vs. fraternal) compare genetic and environmental effects on traits 

• Evolutionary psychology investigates how natural selection shapes behavior, considering reproductive success 

• Evolutionary adaptations are traits evolved for survival and reproduction 

• Cultural variation significantly influences human behavior 

• Experiences impact brain development 

• Habituation is decreased responsiveness to repeated stimuli 

• Synaptic pruning eliminates weak synaptic connections 

The Biology of Mind

• Neurons communicate through electrochemical signals 

• Synapses are the junctions between neurons 

• Neurotransmitters are chemical messengers 

• Action potentials are rapid changes in electrical potential 

• Resting potential is the neuron's stable electrical charge 

• Intensity and firing rate both influence signal strength 

• Grey matter contains cell bodies and dendrites, white matter consists of myelinated axons and glial cells 

• Different brain regions (frontal, occipital, temporal, parietal lobes) have specialized functions 

• The corpus callosum connects the left and right hemispheres 

• Broca's aphasia affects speech production, Wernicke's aphasia affects language comprehension 

Sensation and Perception

• Sensation involves detecting physical stimuli, perception involves interpreting them 

• Bottom-up processing involves building perceptions from sensory input, top-down processing uses existing knowledge to guide sensory information 

• Transduction converts physical stimuli into neural signals 

• Absolute thresholds define the minimum stimulus intensity for detection 

• Subliminal stimuli are below the absolute threshold 

• Priming involves activating related concepts in memory, influencing perception 

• Weber's Law describes the relationship between stimulus change and perceived change 

• Sensory adaptation is reduced sensitivity to constant stimuli 

• Wavelength, hue, and amplitude determine light properties 

Development

• Developmental Psychology examines changes across the lifespan 

• Teratogens are environmental agents harming prenatal development 

• Fetal alcohol syndrome (FAS) is a consequence of prenatal alcohol exposure 

• Synaptic pruning is the elimination of weak synapses during development 

• Myelination is the process of creating myelin sheaths for neurons to improve neural transmission speed 

• Newborn reflexes are innate responses to stimuli 

• Visual preference paradigm tests infant perception 

• Sensitive and critical periods are specific times for development 

Learning

• Classical conditioning involves associating two stimuli, operant conditioning involves associating behavior with consequences 

• Reinforcement strengthens behavior, punishment weakens it 

• Reinforcement schedules involve varying when or how often reinforcement occurs 

• Shaping involves reinforcing successive approximations of a desired behavior 

Memory

• Encoding, storage, and retrieval are the processes of memory 

• Ebbinghaus's retention curve illustrates forgetting curves 

• Sensory memory is a brief initial stage of memory, iconic memory is visual sensory memory, short-term memory is temporary memory, long-term memory is permanent memory; Chunking improves short-term memory 

• Declarative memory involves facts and events (episodic and semantic), implicit memory involves unconscious knowledge 

• Encoding specificity principle states that retrieval is more effective when the context at encoding and retrieval is similar 

Emotion

• Theories of emotion explain how emotions arise (James-Lange, Cannon-Bard, Two-Factor) 

• Facial expressions are a universal way to display emotional states 

• Misattribution of arousal is attributing arousal to the wrong source 

Personality

• Personality refers to enduring patterns of thoughts, feelings, and behaviors 

• Freud's structural model (id, ego, superego) describes personality structures 

• Defense mechanisms protect the ego 

• Trait theories identify and measure traits like the "Big Five" dimensions (Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism) 

Social Psychology

• Social psychologists study how people influence each other 

• Attribution theory explains how we interpret behavior 

• Fundamental attribution error is overemphasizing internal factors in explanations of others' behavior 

• Attitudes are enduring evaluations of people, objects, and ideas, leading to persuasion attempts 

• Attitudes are significantly influenced by persuasion approaches (central and peripheral) 

• Conformity, obedience (e.g., Milgram experiments), prejudice, and reducing prejudice are key areas of study

Psychological Disorders

• Psychological disorders are characterized by maladaptive patterns of thoughts, feelings, and behaviors 

• The DSM-5 classifies mental disorders 

• Depressive disorders, including major depressive disorder, are common psychological disorders