More to this section coming soon!
65% Psychology, 30% Sociology, and 5% Biology.
To do well in this section make sure to understand all of the concepts listed below, practice interpreting data, as well as spend at least half of the time preparing for this section by completing practice passages and tests. For the official content listing look at the AAMC official exam content. All of the content covered in the section is listed below. One thing to keep in mind, however, is that it is not necessary to know every single concept listed below to do well on the MCAT. It is more important to have a strong grasp of the main concepts and be able to apply them. This is a list of every possible topic that may be covered on this part of the exam. It is important to know who is paired with what theories.
Sensation and Perception
Sensory Processing (PSY, BIO)
- Sensation is the detection of external stimuli. Some examples of sensation are hearing, seeing, etc…
- Note that perception occurs after sensation and is the processiong of the stimuli.
- Absolute Threshold
- Absolute Threshold is the lowest intensity of a stimulus that can be detected.
- Weber’s Law
- Weber’s law says the change in intensity of a stimulus needed to be detected is proportional to the intensity of the original stimulus.
- Signal detection theory
- A person’s ability to perceive a stimulus is affected by both the intensity of the stimulus and the person’s physical and psychological state (like how alert they are).
- Sensory adaptation
- Adaption is a decrease in the response after repeated stimulation. An example is a decrease in smelling a particular odor over time.
- Psychophysics is a field of study that investigates the relationship between physical stimuli and the intensity of sensation and perception produced.
- Weber’s law can be thought of as a part of psychophysics.
- Sensory receptors
- Sensory pathways
- The sensory pathway begins at the organ that detected the stimulis, then travels via a connection of nerves to the brain or spinal cord.
- Types of sensory receptors
- There are many types of sensory receptors. To understand them all, look at the prefixes to remember which name goes with what function:
- Mechanoreceptors = detect mechanical stimuli such as external pressure and vibration
- Thermoreceptors = detect temperature
- Nociceptors = detect pain
- Photoreceptor = detects light
- Chemoreceptor = detects chemicals
Vision (PSY, BIO)
- Structure and function of the eye
- When light enters the eye, it first passes through the cornea (outer protective covering) and then enters through the pupil. The light is refracted as it travels through the lens. The refracted light is then projected onto the retina, which covers the whole back wall of the eyeball.
- The retina is made of a layers of many cells. Light activates the photoreceptors, causing them to send a cascade of signals, ultimately leading to a chain of action potentials down the optic nerve into the brain.
- Visual processing
- Visual pathways in the brain
- Action potentials travel through the optic nerve, and cross to the other side of the body at the optic chiasm. After crossing, they travel to the lateral geniculate nucleus (LGN) of the thalamus,
- Parallel processing
- The brain uses multiple pathways to convey different pieces of information about the same stimulus. This allows people to be able to perceive multiple things about a stimulus at the same time. For example, humans can perceive the motion, color, and texture of an
- Feature detection
- Feature detection is a process of the brain where specialized brain centers respond to particular types of visual stimulus. For example, there are certain cells that respond to lines, edges, or angles.
Hearing (PSY, BIO)
- Structure and function of the ear
- After the pinna of the ear (visible portion of the ear) collects and amplifies the sound waves, they travel through the ear canel and cause the eardrum to vibrate. The vibrating eardrum causes three small bones in the middle ear to vibrate, causing the oval window to vibrate. Vibration of the oval window sense waves through the fluid-filed cochlea. These vibrations trigger the motion of tiny hair cells on the basal membrane (which is throughout the cochlea). The movement of these hair cells triggers nerve impulses in the auditory nerve.
- Auditory processing (e.g., auditory pathways in the brain)
- Nerve impulses travel from the auditory nerve to the thalamus. From there, they travel to the auditory cortex in the temporal lobe.
- Sensory reception by hair cells
- The pulses within the fluid of the cochlea cause vibrations in the basal membrane, which pushes hair cells. The hair cells, when pushed, open ion channels which causes a depolarization of the hair cell. This depolarizes the auditory nerve.
Other Senses (PSY, BIO)
- Somatosensation (e.g., pain perception)
- Somatosensation is sensation from the skin as a result of pressure, vibration, or pain. Nociceptors deep in the skin are activated when they sense pain. These receptors send signals to the spinal cord, which sends the signal to the brain.
- Taste (e.g., taste buds/chemoreceptors that detect specific
- Tastebuds have different channels that detect specific chemicals.
- Olfactory cells/chemoreceptors that detect specific
- Pheromones (BIO)
- Olfactory pathways in the brain (BIO)
- Kinesthetic sense (PSY)
- Kinesthetic sense is the ability to sense the position and movement of the parts of the body. For example, the detection of the position of one’s arm.There are sensors within muscles that detect whether they are streched or flexed.
- Vestibular sense
- The vestibular sense is the detection of acceleration as well as whether the head is tilted. For example, you can tell that your body within a car is accelerating due to your vestibular sense.
- Bottom-up/Top-down processing
- Perception can be divided into two major types of organization: bottom-up and top-down.
- Bottom-up processing: The interpretation of sensory information as it comes in. So in this method of processing your brain is like a blank state and takes all of the information it receives and pieces it together to form an overall picture.
- Top-down processing: The brain starts by understanding the bigger picture and then begins focusing on the details. With top-down processing, your expectations can influence what is perceived.
- Perceptual organization (e.g., depth, form, motion, constancy)
- Perceptual organization involves the brain compartmentalizing different aspects of an object into smaller parts that are easier to keep track of.
- Depth: Our perception of how far an object is from us.
- Form: Form is the interpretation of the outline of an object.
- Motion: The human retina is able to detect whether or not an object is moving.
- Constancy: The brain has an ability to recognize when an object is not changing, even if its appearance changes. For example, if the light source on an object changes so it is illuminated in a different way, the brain can still interpret the object as not change.
- Gestalt principles
- The idea behind the gestalt principles is that the whole is greater than the sum of its parts. For example, the brain is wired to perceive bigger-picture details of an object and automatically group objects together. Our brain is wired to group things that have similarity, proximity (are near each other), continuity (for example dots that form a single line will automatically be grouped together into one object), and closure (lines that enclose a space are grouped together).
Understanding our Environment
- Selective attention
- Selective attention is our ability to focus on a particular stimulus while not paying attention to unimportant stimuli. For example, we are able to focus on one particular conversation in a loud room full of people.
- Divided attention
- Divided attention is the ability to divert some of our attention to complete multiple tasks simultaneously. This usually declines the performance on at least one of the tasks being performed. For example, texting while driving splits attention between the two tasks and lowers performance of driving the car.
- Information-processing model
- This model compares the human mind to a computer that takes in information and then processes the information in a certain way to lead to the output, which is the behavior. A computer receives data, processes it, and has an output. For a human, this could be feeling cold. The input is from the thermoreceptors receiving the stimulus of the cold temperature, the processing is the brain interpreting these signals from the thermoreceptors as a sign that the body is cold, and the output would be going to get a warm jacket. The information is transformed into a behavior using different ways of processing the information depending on what the information is.
- Cognitive development
- Piaget’s stages of cognitive development
- Piaget described four stages of development. The sensorimotor period, the preoperational period, the concrete operational period, and the formal operational period. These stages mark the development of cognitive processing skills.
- Sensorimotor stage: This stage occurs from birth until 2 years of age. In this stage children learn about the world through their senses. They also start to develop a sense of object permanence.
- Preoperational stage: This stage occurs from ages 2 to 7. In this stage the child begins to speak and understand that symbols (such as words) can represent objects. Their developing use of symbols allows them to pretend play (dress up as superheros, etc…). The child is still very egocentric at this time.
- Concrete operational: This stage occurs from age 7 to age 11. During this stage the child begins to think more logically. In this stage the child also learns the principle of conservation. For example, one sandwich cut into two halves is still perceived as the same amount of food after a child has learned the principle of conservation.
- Formal operational: This stage occurs after the age of 12 through adulthood. In this stage the person learns to think abstractly and reason about morals.
- Cognitive changes in late adulthood
- Over the age of 65, an individuals memory, especially that of recall, is greatly affected. Also, information-processing takes longer than it does for middle-aged individuals.
- Role of culture in cognitive development
- Lev Vygotsky’s theory of sociocultural development places a lot of weight on the influence of culture in cognitive development. He stresses that culture significantly affects cognitive development (and that it varies across cultures.
- Influence of heredity and environment on cognitive
- One fundamental debate is the idea of “nature” vs. “nurture”. This debate is somewhat misleading because really it is a combined influence of the two that governs development. For instance, genes can predispose an individual to depression, but whether or not they develop depression is determined by their environment.
- Biological factors that affect cognition (PSY, BIO)
- The hippocampus is responsible for forming new memories within the brain.
- The frontal lobe allows for planning and organization.
- Problem solving and decision making
- Types of problem solving
- Trial and error: Various solutions are attempted until the individual finds one that works
- Heuristics: Heuristics are a shorthand way to make decisions based on previous experiences. This method is inaccurate but very quick and effective.
- Algorithm: The calculated process of finding the solution to a problem. Algorithms take a long time but are very accurate.
- Barriers to effective problem solving
- Functional fixedness: the inability to think of uses for an object different than their prescribes use.
- Confirmation bias: the tendency to only pay attention to information that supports an individual’s belief and ignore information that contradicts it.
- Mental set: This is tendency to fixate on solutions that ave worked in the past instead of considering other ideas.
- Heuristics and biases (e.g., overconfidence, belief
- Availability heuristic: the information most immediately available in a person’s mind has a great impact when evaluating a concept or problem.
- Representative heuristic: People have a tendency to make judgements based on previous beliefs or experiences. One big weakness about this heuristic is that it can lead people to be vulnerable to being closeminded and believing incorrect stereotypes.
- Overconfidence: Research has shown that the confidence people have about their answers is greater than their accuracy.
- Belief perseverance: A tendency to hold onto our beliefs, even if presented with facts or situations that prove them to be untrue.
- Fundamental attribution error: People tend to attribute failures as being the fault of others, but successes as being because of their own actions.
- Intellectual functioning
- Theories of intelligence
- There are several different theories of intelligence. The G factor ranges from just one general scale of intelligence, while another theory describes eight separate different types of intelligence. There are also several other different theories. It is important to recognize who created which theory.
- The G factor, by Charles Spearman proposed that there is just one scale of general intelligence. There is some support for this theory, as well as some conflictual evidence.
- Howard Gardner proposed that there are eight separate types of intelligence: linguistic, logical-mathematical, musical, spatial, interpersonal, intrapersonal, and understanding of the natural world (science).
- Triarchic theory of intelligence was created by Robert Sternberg that distinguishes three aspects of intelligence: componential intelligence (the type of intelligence tested by intelligence tests, similar to IQ), experiential intelligence (being able to adapt to new situations and create new ideas), and contextual intelligence (the ability to function well in daily life).
- The theory of primary mental abilities, by L. L. Thurnstone describes 7 different faucets of intelligence: verbal comprehension, verbal fluency, mathematical ability, memory, perceptual speed, inductive reasoning, and spatial visualization.
- It is also important to understand crystallized intelligence vs. fluid intelligence. Crystallized intelligence is a knowledge of facts, where fluid intelligence is the ability to think problem solve and reason quickly.
- Influence of heredity and environment on intelligence
- Genetics tend to predispose an individual to fall within a certain range of intelligence. One’s environment determines where the individual falls within this range. For example, if one is in a stimulating, nourishing environment they will fall to the top of that range. Harsh stressors such as alcohol while in the womb, malnourishment, or extreme stress and trauma will lower the intelligence.
- Variations in intellectual ability
- Variations in intellectual ability can be measured one way using the intelligence quotient (IQ). This test gives someones IQ as a fraction of their mental age vs. their physical age multiplied by 100. So an average IQ is 100. Variations can be attributed to genes, environment, and one’s access to quality education. Some parts of one’s intelligence can also change as they age.
- States of consciousness
- Consciousness is defined as one’s awareness of themselves and their body. An individual is very conscious when they are alert and going about activities during the day. They are less conscious while sleeping, especially during certain stages of sleep.
- Alertness (PSY, BIO)
- Stages of sleep
- Sleep cycles and changes to sleep cycles
- Sleep and circadian rhythms (PSY, BIO)
- Sleep–wake disorders
- Hypnosis and meditation
- Consciousness-altering drugs
- Types of consciousness-altering drugs and their effects on the
nervous system and
- Drug addiction and the reward pathway in the brain
- Process of encoding information
- Processes that aid in encoding memories
- Types of memory storage (e.g., sensory, working, long-term)
- Semantic networks and spreading activation
- Recall, recognition, and relearning
- Retrieval cues
- The role of emotion in retrieving memories (PSY, BIO)
- Processes that aid retrieval
- Aging and memory
- Memory dysfunctions (e.g., Alzheimer’s disease, Korsakoff’s
- Memory construction and source monitoring
- Changes in synaptic connections underlie memory and learning
- Memory and learning
- Long-term potentiation
- Neural plasticity
- Theories of language development (e.g., learning, Nativist,
- Influence of language on cognition
- Brain areas that control language and speech (PSY, BIO)
Responding to the Environment
- Three components of emotion (i.e., cognitive, physiological,
- Universal emotions (i.e., fear, anger, happiness, surprise,
joy, disgust, and sadness)
- Adaptive role of emotion
- Theories of emotion
- James–Lange theory
- Cannon–Bard theory
- Schachter–Singer theory
- The role of biological processes in perceiving emotion (PSY,
- Brain regions involved in the generation and experience of
- The role of the limbic system in emotion
- Emotion and the autonomic nervous system
- Physiological markers of emotion (signatures of emotion)
- The nature of stress
- Different types of stressors (e.g., cataclysmic events,
- Effects of stress on psychological functions
- Stress outcomes/response to stressors
- Physiological (PSY, BIO)
- Managing stress (e.g., exercise, relaxation, spirituality)
Individuals and Behavior
Biological Bases of Behavior (PSY, BIO)
- The nervous system
- Neurons (e.g., the reflex arc)
- Structure and function of the peripheral nervous system
- Structure and function of the central nervous system
- The brain
- Lateralization of cortical functions
- Methods used in studying the brain
- The spinal cord
- Neuronal communication and its influence on behavior (PSY)
- Influence of neurotransmitters on behavior (PSY)
- The endocrine system
- Components of the endocrine system
- Effects of the endocrine system on behavior
- Behavioral genetics
- Genes, temperament, and heredity
- Adaptive value of traits and behaviors
- Interaction between heredity and environmental influences
- Influence of genetic and environmental factors on the
development of behaviors
- Experience and behavior (PSY)
- Regulatory genes and behavior (BIO)
- Genetically based behavioral variation in natural
- Human physiological development (PSY)
- Prenatal development
- Motor development
- Developmental changes in adolescence
- Theories of personality
- Psychoanalytic perspective
- Humanistic perspective
- Trait perspective
- Social cognitive perspective
- Biological perspective
- Behaviorist perspective
- Situational approach to explaining behavior
Psychological Disorders (PSY)
- Understanding psychological disorders
- Biomedical vs. biopsychosocial approaches
- Classifying psychological disorders
- Rates of psychological disorders
- Types of psychological disorders
- Anxiety disorders
- Obsessive–compulsive disorder
- Trauma- and stressor-related disorders
- Somatic symptom and related disorders
- Bipolar and related disorders
- Depressive disorders
- Dissociative disorders
- Personality disorders
- Biological bases of nervous system disorders (PSY, BIO)
- Alzheimer’s disease
- Parkinson’s disease
- Stem cell-based therapy to regenerate neurons in the central
nervous system (BIO)
- Factors that influence motivation
- Drives (e.g., negative feedback systems) (PSY, BIO)
- Theories that explain how motivation affects human behavior
- Drive reduction theory
- Incentive theory
- Other theories (e.g., cognitive, need-based)
- Biological and sociocultural motivators that regulate behavior
(e.g., hunger, sex drive, substance addiction)
- Components of attitudes (i.e., cognitive, affective, and
- The link between attitudes and behavior
- Processes by which behavior influences attitudes (e.g.,
foot-in-the door phenomenon,
- role-playing effects)
- Processes by which attitudes influence behavior
- Cognitive dissonance theory
Social Influences on Behavior
How the Presence of Others Affects Individual Behavior (PSY)
- Social facilitation
- Bystander effect
- Social loafing
- Social control (SOC)
- Peer pressure (PSY, SOC)
- Conformity (PSY, SOC)
- Obedience (PSY, SOC)
Group Decision-making Processes (PSY, SOC)
- Group polarization (PSY)
Normative and Non-normative Behavior (SOC)
- Social norms (PSY, SOC)
- Sanctions (SOC)
- Folkways, mores, and taboos (SOC)
- Anomie (SOC)
- Perspectives on deviance (e.g., differential association,
labeling theory, strain theory)
- Aspects of collective behavior (e.g., fads, mass hysteria,
Socialization (PSY, SOC)
- Agents of socialization (e.g., the family, mass media, peers,
Learning and Attitude
Habituation and Dishabituation (PSY)
Associative Learning (PSY)
- Classical conditioning (PSY, BIO)
- Neutral, conditioned, and unconditioned stimuli
- Conditioned and unconditioned response
- Processes: acquisition, extinction, spontaneous recovery,
- Operant conditioning (PSY, BIO)
- Processes of shaping and extinction
- Types of reinforcement: positive, negative, primary,
- Reinforcement schedules: fixed-ratio, variable-ratio,
- Escape and avoidance learning
- The role of cognitive processes in associative learning
- Biological processes that affect associative learning (e.g.,
biological predispositions, instinctive drift) (PSY, BIO)
Observational Learning (PSY)
- Biological processes that affect observational learning
- Mirror neurons
- Role of the brain in experiencing vicarious emotions
- Applications of observational learning to explain individual
Theories of Attitude and Behavior Change (PSY)
- Elaboration likelihood model
- Social cognitive theory
- Factors that affect attitude change (e.g., changing behavior,
characteristics of the message and target, social factors)
Self-Concept, Self-identity, and Social Identity (PSY, SOC)
- The role of self-esteem, self-efficacy, and locus of control
in self-concept and self-identity (PSY)
- Different types of identities (e.g., race/ethnicity, gender,
age, sexual orientation, class)
Formation of Identity (PSY, SOC)
- Theories of identity development (e.g., gender, moral,
- Influence of social factors on identity formation
- Influence of individuals (e.g., imitation, looking-glass
- Influence of groups (e.g., reference group)
- Influence of culture and socialization on identity formation
Attributing Behavior to Persons or Situations (PSY)
- Attributional processes (e.g., fundamental attribution error,
role of culture in attributions)
- How self-perceptions shape our perceptions of others
- How perceptions of the environment shape our perceptions of
Prejudice and Bias (PSY, SOC)
- Processes that contribute to prejudice
- Power, prestige, and class (SOC)
- The role of emotion in prejudice (PSY)
- The role of cognition in prejudice (PSY)
- Stigma (SOC)
- Ethnocentrism (SOC)
- Ethnocentrism vs. cultural relativism
Processes Related to Stereotypes (PSY)
- Self-fulfilling prophecy
- Stereotype threat
Elements of Social Interaction (PSY, SOC)
- Status (SOC)
- Types of status (e.g., achieved, ascribed)
- Role conflict and role strain (SOC)
- Role exit (SOC)
- Primary and secondary groups (SOC)
- In-group vs. out-group
- Group size (e.g., dyads, triads) (SOC)
- Networks (SOC)
- Organizations (SOC)
- Formal organization
- Characteristics of an ideal bureaucracy
- Perspectives on bureaucracy (e.g., iron law of oligarchy,
Self-presentation and Interacting with Others (PSY, SOC)
- Expressing and detecting emotion
- The role of gender in the expression and detection of
- The role of culture in the expression and detection of
- Presentation of self
- Impression management
- Front stage vs. back stage self (Dramaturgical approach)
- Verbal and nonverbal communication
- Animal signals and communication (PSY, BIO)
Social Behavior (PSY)
- Social support (PSY, SOC)
- Biological explanations of social behavior in animals (PSY,
- Foraging behavior (BIO)
- Mating behavior and mate choice
- Applying game theory (BIO)
- Inclusive fitness (BIO)
Discrimination (PSY, SOC)
- Individual vs. institutional discrimination (SOC)
- The relationship between prejudice and discrimination
- How power, prestige, and class facilitate discrimination (SOC)
Theoretical Approaches (SOC)
- Microsociology vs. macrosociology
- Conflict theory
- Symbolic interactionism
- Social constructionism
- Exchange-rational choice
- Feminist theory
Social Institutions (SOC)
- Hidden curriculum
- Teacher expectancy
- Educational segregation and stratification
- Family (PSY, SOC)
- Forms of kinship (SOC)
- Diversity in family forms
- Marriage and divorce
- Violence in the family (e.g., child abuse, elder abuse,
spousal abuse) (SOC)
- Types of religious organizations (e.g., churches, sects,
- Religion and social change (e.g., modernization,
- Government and economy
- Power and authority
- Comparative economic and political systems
- Division of labor
- Health and medicine
- The sick role
- Delivery of health care
- Illness experience
- Social epidemiology
Culture (PSY, SOC)
- Elements of culture (e.g., beliefs, language, rituals,
- Material vs. symbolic culture (SOC)
- Culture lag (SOC)
- Culture shock (SOC)
- Assimilation (SOC)
- Multiculturalism (SOC)
- Subcultures and countercultures (SOC)
- Mass media and popular culture (SOC)
- Evolution and human culture (PSY, BIO)
- Transmission and diffusion (SOC)
Demographic Structure of Society (PSY, SOC)
- Aging and the life course
- Age cohorts (SOC)
- Social significance of aging
- Sex versus gender
- The social construction of gender (SOC)
- Gender segregation (SOC)
- Race and ethnicity (SOC)
- The social construction of race
- Racial formation
- Immigration status (SOC)
- Patterns of immigration
- Intersections with race and ethnicity
- Sexual orientation
Demographic Shifts and Social Change (SOC)
- Theories of demographic change (i.e., Malthusian theory and
- Population growth and decline (e.g., population projections,
- Fertility, migration, and mortality
- Fertility and mortality rates (e.g., total, crude,
- Patterns in fertility and mortality
- Push and pull factors in migration
- Social movements
- Relative deprivation
- Organization of social movements
- Movement strategies and tactics
- Factors contributing to globalization (e.g., communication
- Perspectives on globalization
- Social changes in globalization (e.g., civil unrest,
- Industrialization and urban growth
- Suburbanization and urban decline
- Gentrification and urban renewal
Spatial Inequality (SOC)
- Residential segregation
- Neighborhood safety and violence
- Environmental justice (location and exposure to health risks)
Social Class (SOC)
- Aspects of social stratification
- Social class and socioeconomic status
- Class consciousness and false consciousness
- Cultural capital and social capital
- Social reproduction
- Power, privilege, and prestige
- Intersectionality (e.g., race, gender, age)
- Socioeconomic gradient in health
- Global inequalities
- Patterns of social mobility
- Intergenerational and intragenerational mobility
- Vertical and horizontal mobility
- Relative and absolute poverty
- Social exclusion (segregation and isolation)