Psych/Soc MCAT

Social Effects on Behavior 

Effects of Groups on Individual Behavior

• Social facilitation - people perform tasks better in group settings where psychological arousal is higher 

  • For simple/familiar tasks, the relationship between psychological arousal and performance is linear  

  • Yerkes-Dodson Law - For complex/technical tasks, the relationship between psychological arousal and performance creates a U-shaped graph - the best performance under moderate arousal 

• Social loafing - the idea that people tend to work less hard in a group setting as other people pick up the slack  

  • Often not a deliberate choice 

• Bystander Effect - refers to people’s tendency to not offer help to someone if other bystanders are present 

  • First reason: Diffusion of responsibility in a crowd 

  • Second reason: we model our behavior based on those around us 

  • Third reason: social etiquette 

• Deindividuation - loss of sense of self-awareness in a large group 

  • Due to a high psychological arousal and lower perceived responsibility 

  • Three main factors contribute to deindividuation: 

    • Anonymity 

    • Diffused responsibility - sense that you are not really responsible for what happens 

    • Group size 

Group Polarization and Groupthink 

• Group Polarization - a group of people will arrive at final opinions that are more extreme than the initial positions of the individual members 

  • Famously occurs when people talk about politics (foundation for the concept of an echochamber) 

  • Contributing factors to group polarization: 

    • Informational influence: people in a group are more likely to express points in line with the dominant viewpoint 

    • Normative Influence: our desire to be socially accepted, affirmed, or admired within group 

• Groupthink - irrational decisions are made within a group due to pressures towards harmony and individual conformity 

  • Always involves irrational decisions made by a group 

  • 8 specific factors that are characteristics of groupthink: 

1. Illusion of invulnerability - belief that no serious harm will come to the group leading to higher chances of making rash decisions 

2. Illusion of morality - unbending belief in the moral righteousness of the group's cause 

3. Illusion of Unanimity - the group assumes that the majority of opinions in the group of unanimous

4. Self-censorship - members who do disagree do not share their opinion 

5. Pressure on Dissenters - members feel pressure not to contradict the majority group 

6. Collective Rationalization - when a group comes up with an explanation to ignore dissenting opinions that come from outside the group 

7. Excessive Stereotyping - negative views of outside opinions 

8. Mind Guards - certain members of the group filter out information that could destabilize consensus  

Conformity, Compliance, and Obedience 

• Conformity - a general concept that describes when someone’s behavior, beliefs, or thinking changes to line up with the perspectives of others 

  • Internalization/Conversion - genuine change in someone’s beliefs possibly resulting from conformity 

  • Identification - a middle ground between internalization and compliance in which someone’s behaviors and beliefs change but only in the presence of the group

  • Compliance to Conformity - when a person practices conformity but internally dissents

• Compliance - responses to requests from someone with no power to enforce that request 

  • Compliance Tactics: 

1. Foot-in-the-door Technique - making a small request, followed by a larger request; positively responding to a small request makes it more likely that person will respond positively to a larger request 

2. Door-in-the-Face Technique - making a large request you know will be rejected, only to follow it up with a smaller, more reasonable request 

3. Low Ball Technique - Offering a low price, only to raise it at the last minute 

• Obedience - a change in behavior in response to a direct request from someone with power to enforce that request 

  • Milgram Experiment - shocks 

  • Stanford Prison Experiment 

Social Norms, Deviance, and Socialization 

• Social Norms - rules that regulate behavior, beliefs, attitudes, and values of members of society 

  • Formal Norms - must be encoded somewhere, where specific penalties for violations 

  • Informal Norms - not written down; simply expectations with no fixed specialties for violating them 

    • Folkways - insignificant informal norms that involve small details 

      • Ex. fashion trends, holding the door, etc 

    • Mores - informal norms which incur severe disapproval when violated 

      • Ex. adultery, being rude to retail workers, etc 

  • Taboos - even more restrictive norms that generate extreme disapproval 

    • Ex. incest, cannibalism 

    • Blur the line between formal and informal norms 

  • Anomie - refers to a situation where there is a poor match between society’s stated norms and the norms that an individual responds to 

    • Occurs when social norms have changed to the point of being mismatched with his own views 

• Social control - the way these norms are taught, enforced, and perpetuated 

  • Sanctions - punishment or negative consequence for violating a social norm AND rewards for following a social norm 

  • Peer pressure - the desire for approval or fear of disapproval can be a powerful motivator 

• Deviance - occurs when someone does not follow a norm 

  • Trivial or serious

  • Differential Association Theory - views deviance as behavior that is learned socially 

  • Labeling Approach - focuses on how behavior is affected by being labeled as a deviant 

    • Primary deviance - deviant acts committed before being labeled 

    • Secondary deviance - deviant acts committed after being labeled partially in reaction to the label 

  • Strain Theory - theory of deviance suggesting that when individuals are pushed to achieve socially acceptable goals, but only have socially unacceptable means of achieving those goals, they may become deviant 

    • Says that some people would commit crime under straining circumstances

• Socialization - how we learn informal and formal norms by interacting with other people and institutions 

  • Agents of socialization: 

    • Family 

    • Educational system 

    • Mass media 

    • Workplace 

    • Peers 

Aspects of Collective Behavior

• Fads - a new behavior that suddenly becomes extremely popular, then fades 

  • Do not stand well to time 

• Mass Hysteria - irrational fear of a perceived threat, verging on the point of a collective delusion

• Riots - spontaneous episodes of civil disorder normally targeted against an established institution or authority figure 

  • Normally including vandalism or property destruction

  • Classic example of disindividuation 

Biological Fundamentals of Behavior 

 Conceptual Approaches to Behavior 

• Ekman’s List of Universal Emotions 

  • Happiness 

  • Surprise 

  • Sadness 

  • Fear 

  • Disgust 

  • Contempt 

  • Anger 

High Level Theoretical Approaches 

• Social Constructionism - a theory of knowledge that posits that reality and knowledge are not inherent or objectively true but are created and maintained through social interactions and shared cultural meaning 

  • Key Idea: There is no single, objective reality independent of human beings; instead, meaning is fluid, evolving, and shaped by cultural and historical contexts.

  • Example: Dollar bills have no inherent value (it cannot be eaten or used for survival). It’s value as a medium of exchange is a social construct because society has collectively agreed that this piece of paper represents a certain worth and can be exchanged for goods and services 

• Symbolic Interactionism - a micro-level sociological framework that focuses on how individuals derive and interpret meaning through their face-to-face social interactions 

  • Key Idea: Society is the product of everyday human interactions. People act toward objects, events, or people based on the meanings they assign to them, and these meanings are formed through social interaction.

  • Example: the Thumbs-up Gesture has no intrinsic meaning, but its meaning arises from the social interactions and shared understanding within a society 

• Functionalism - All of society should serve a function for the society; views society has a complex, stable system whose parts work together to promote stability and social order 

  • Key Idea: Different institutions (family, government, economy, education, etc) each fulfill a specific function essential for the whole system’s survival and maintenance 

    • Manifest Functions: the recognized and intended consequences of a social institution (eg. the manifest function of education is to transmit knowledge and skills) 

    • Latent Functions: the unrecognized and unintended consequences (e.g. a latent function of education is matching students into marriage partners or building social networks)

  • Critique: Because Functionalism focuses on stability and consensus, critics argue it struggles to explain dramatic social change, conflict, and deeply rooted inequalities.

• Conflict Theory - a macro-level perspective that sees society an an arena of inequality that generates conflict and social change 

  • Key Idea: Social order is a temporary state maintained by the dominance of certain groups over others. Conflict is inevitable and even necessary for transformative social change.

  • Resource Competition: Conflict arises from the competition between groups (defined by class, race, gender, etc.) for limited resources—social, material, and political—such as housing, employment, and education. 

Genetics and Development 

• Temperament - how an individual responds behaviorally and emotionally to stimuli from the world that surrounds them 

• Heritability - the degree of variation in a trait due to variation in the genotype

  • Heritability = 1 → all variation in a trait is purely explained by genetics 

  • Heritability = 0 → all variation can be explained by environmental factors 

• Twin and adoption studies are very helpful for this purpose 

•  Variations in promoters and regulatory genes might share behavior  

• Epigenetics - changes to the genome that does not involve changing the actual nucleotide content 

  • Methylation - adding methyl groups to cytosine which silences DNA 

  • Certain methylation patterns can be inherited 

Human Psychological Development 

Pregnancy 

• At 12 weeks - The fetus is very small but the basic structure of the organ system has been formed

• Second trimester - the details get filled in and the fetus grows 

• Third Trimester - fetus grows and finalizing preparations for the outside world 

• The placenta enables two way communication between the fetus and the mother 

• Psychological and nutrition factors during pregnancy can affect the health of the baby 

Infancy-Childhood 

• Palmar grasp reflex 

• Rooting - babies will search for an object that brushes against its mouth or cheek 

• Sucking - the baby will make sucking noises automatically when something grazes the top of its mouth 

• Moro Reflex - in response to sudden movement or loud sounds in which the baby will extend its arms, throws back its head, and cries

• Babinski Reflex - stroke the bottom of the foot, the toes fan out 

Developmental Stages 

• Walking at about 1 year old 

• 2 year olds can draw basically, kick, or stack toys 

  • Dramatic increase in language usage 

• 2-3 years 

  • Toilet training 

  • Awareness of gender 

  • Language development 

• Adolescence - the transition from childhood to adulthood 

  • Puberty - refers to the specific biological changes that occur during adolescence 

  • Secondary sex characteristics develop due to sex hormones like testosterone and estradiol 

• Aging - involved a gradual physical decline as people become more frail and disease prone 

  • Fluid intelligence and mental processes speed decrease 

  • Fluid intelligence - your innate ability to think abstractly, reason, solve novel problems, and adapt to new situations, relying on logic and pattern recognition rather than past knowledge

  • Crystallized intelligence - knowledge accumulated over time 

Behavior and the Endocrine Nervous System

The Endocrine System - network of organs that secrete hormones into the bloodstream and throughout the body to exert their effects  

• Tropic Hormones - hormones that cause secondary hormones to be released 

• Direct Hormones - hormones that cause a direct effect 

• Organs in the Endocrine System: Hypothalamus, Pituitary gland, thyroid gland, thymus gland, adrenal gland, pancreas, ovaries 

  • Hypothalamus - converts nervous system input into endocrine signals; releases hormones that travel to the anterior pituitary 

    • Gonadotropin-Releasing Hormone (GnRH) - acts on the anterior pituitary; it triggers the release of luteinizing hormone (LH) and follicle stimulating hormone (FSH)

    • Corticotropin-Releasing Factor (CRH)- promotes the release of adrenocorticotropic hormone (ACTH) from the anterior pituitary which eventually stimulates the adrenal gland to release cortisone 

    • Thyrotropin-Releasing Hormone (TRH)- stimulates the release of thyroid stimulating hormone (TSH) to be released from the anterior pituitary which promotes thyroid hormone production 

  • Anterior Pituitary 

    • In addition to LH, FSH, ACTH, and TSH, it also produces…

    • Prolactin - stimulates milk production 

    • Endorphins - reduce the perception of pain 

    • Growth Hormone 

  • Posterior Pituitary - also received information from the hypothalamus but in the form of neuronal, rather than hormonal signals 

    • Antidiuretic Hormone (ADH) 

    • Oxytocin 

  • Thyroid Gland - releases thyroid hormone affecting metabolism and behavior  

  • Adrenal Glands - small glands located on top of the kidneys  

    • Cortex - secretes cortisol which mediates the stress response  

    • Medulla - secretes epinephrine and norepinephrine   

  • Ovaries and Testicles 

Endocrine System and Behavior 

• Some behaviors are known to either increase or decrease the levels of estrogen/testosterone 

• Oxytocin  - known for promoting uterine contractions during labor 

  • More oxytocin → more contractions → more oxytocin (until childbirth) 

  • coordinates behaviors regarding bonding, mood, and affection

• Prolactin - helps induce lactation for breastfeeding 

  • Also modulates stress response, anxiety, and depression

  • Disregulation of prolactin is a contributor to post-partum depression 

• Melatonin - produced by the pineal gland in the brain and regulates wakefulness

• Leptin, Ghrelin, and Neuropeptide Y - modulate hunger 

  • Leptin reduces hunger - primarily reduced by adipose tissue 

  • Ghrelin promotes hunger - released by cells in the GI tract

  • Neuropeptide Y stimulates appetite to increase food intake  

• Thyroid Hormone - promotes metabolism and needed for proper neurological development 

  • Hypothyroidism - present with fatigue, depression, weight gain 

  • Hyperthyroidism - present with aggression and weight loss 

  • Thyroxine - secreted by the thyroid to regulate metabolism. Excess thyroxine would speed up metabolism which would likely lead to increased hunger 

Mechanisms of the Nervous System 

• Acetylcholine - responsible for activating muscle contraction by synapsing on target muscle cells  

  • Communicates signals between the central nervous system and the autonomic nervous system

• GABA -  inhibitor neurotransmitter (hyperpolarizing neurons) 

• Glutamate - an excitatory neurotransmitter (depolarizing neurons, pushing them closer to action potential threshold)  

• Endorphines - category of neurotransmitters that suppress pain and produce euphoria 

  • Function similarly to opioids 

• Serotonin - a neuromodulatory that can exhibit both inhibitory and excitatory effects (the receptor determines the effect) and functions to regulate mood, appetite, sleep, and intestinal movement 

  • Depression reflects low serotonin levels 

• Dopamine - involved in reward pathways (and addiction)  

  • Loss of dopamine-secreting neurons in the substantial nigra leads to Parkinson’s disease 

• Norepinephrine - main neurotransmitter involved in the acute stress response

Central Nervous System   

• Cerebellum* - Coordination and Movement: Refines motor movements (smooths them out). Balance: Coordinates posture and balance. Receives information from the cerebral cortex, brain stem, and spinal cord.

• Medulla Oblongata (Medulla)* Vital Reflexes: Controls autonomic functions necessary for life, such as breathing (respiratory center), heart rate, and blood pressure. * The point where most motor and sensory neurons cross between the brain and spinal cord.

• Pons* Bridge: Serves as a relay station, connecting the cerebellum and the medulla to the upper parts of the brain. * Sleep and Arousal: Plays a role in the regulation of sleep, respiration, and facial sensation.

• Reticular Formation* Arousal and Alertness: Extends through the brainstem (midbrain, pons, and medulla). * Governs the overall level of alertness, focus, and consciousness (e.g., waking you from sleep).

• Superior Colliculus* Visual Reflexes: Receives visual sensory input. * Involved in directing eye movements and orientation to visual stimuli (e.g., following a moving object).

• Inferior Colliculus* Auditory Reflexes: Receives auditory sensory input. * Involved in auditory startle reflexes and localization of sound.

• Thalamus* Sensory Relay Station: Serves as the main relay station for almost all incoming sensory information (except smell). * Sorts and transmits sensory impulses to the appropriate areas of the cerebral cortex.

  • Medial Geniculate Nucleus - Receives sensory input from auditory centers (like the Inferior Colliculus) and relays that information to the Primary Auditory Cortex (located in the Temporal Lobe).

  • Lateral Geniculate Nucleus - Receives sensory input directly from the Optic Tract (originating from the retina) and relays that information to the Primary Visual Cortex (located in the Occipital Lobe).

• Hypothalamus* Homeostasis and Drives: Crucial for maintaining homeostasis (temperature, water balance, sleep/wake cycles). The Four F's: Controls the primal drives (Fighting, Fleeing, Feeding, and Fornication/sexual behavior). Endocrine Link: Regulates the pituitary gland (master endocrine gland).

• Basal Ganglia* Motor Control: Coordinates muscle movement. * Smooth Movement: Helps make movements smooth and posture steady; damage can lead to Parkinson's disease.

• Limbic System* Emotion and Memory: Contains structures critical for emotion and memory. * Includes the Amygdala (fear and emotion) and Hippocampus (memory consolidation).

• Cerebral Cortex* Highest Functions: Complex thought, memory, reasoning, language, and voluntary movement. * Divided into four lobes (Frontal, Parietal, Temporal, Occipital).

  • Frontal Lobe* Executive Function: Impulse control, long-term planning, decision-making. Motor Cortex: Initiates voluntary movement. Broca's Area: Speech production.

  • Parietal Lobe* Somatosensory: Contains the Somatosensory Cortex (touch, temperature, pain). * Spatial Sense: Orientation, mapping, and spatial manipulation.

  • Occipital Lobe* Visual Processing: Contains the Visual Cortex. * Involved in sight and processing visual stimuli/information.

  • Temporal Lobe* Auditory Processing: Contains the Auditory Cortex (hearing). Wernicke's Area: Language comprehension. Emotion and Memory: Houses the Hippocampus and Amygdala (Limbic System structures).

Methods of Studying the Brain 

• Electroencephalograms - measure brain activity through electrodes placed on the scalp and measure electrical activity in the brain 

• CT scan - x-rays in 360˚ and assemble the pictures in 3D 

• MRI - uses magnetic fields to make pictures of structures in the body 

  • Better at imaging soft structures and no radiation 

  • More expensive and time consuming   

• Positron Emission Tomography (PET) - works by radiolabeling glucose with 18-F which emits positrons as it decays. The detector analyzes where the decay occurs → where more decay occurs are those were more glucose is being metabolized → more neuronal activity 

• fMRI - relies on differences in magnetic properties between oxygenated (arterial) and deoxygenated (venous) hemoglobin to measure blood flow to predominantly measure brain blood flow  

  • Used to image both the structure and function of the brain 

Theories of Emotion 

• James-Lange Theory of Emotion - suggests that physiological arousal precedes and causes the emotional experience

  • Order of events: stimulus → physiological arousal → emotional experience 

  • Example: You see a bear (Stimulus) → Your heart pounds and you run (Arousal) → You realize, "I am afraid" (Emotion).

• Cannon-Bard Theory of Emotion - a critique of the James-Lange theory, arguing that physiological arousal and emotional experience occur simultaneously. 

  • Order of events: stimulus → physiological arousal AND emotional experience 

  • Example: You see a bear (Stimulus) → Your heart pounds AND you feel fear (Arousal and Emotion are independent and simultaneous).

• Schachter-Singer Theory (Two-Factor Theory) of Emotion - introduces the concept of cognitive appraisal (labeling) as the critical step that transforms arousal into a specific emotion. Arousal is interpreted based on the context to determine the feeling.

  • Order of Events: Stimulus → Physiological Arousal → Cognitive Appraisal (Labeling) → Emotional Experience

  • Example: You see a bear and your heart pounds (Arousal). You look around and realize you are in a safe zoo enclosure (Appraisal). You label the feeling as excitement rather than fear (Emotion).

• Lazarus Theory of Emotion - places cognitive appraisal as the first step. The appraisal (labeling the situation as good or bad, threatening or safe) determines both the physiological response and the emotional experience.

  • Order of Events: Stimulus → Cognitive Appraisal → Physiological Arousal and Emotional Experience 

  • Example: You see a bear (Stimulus) → You instantly realize, "That is a danger to me!" (Appraisal) → This causes your heart to pound and you feel fear simultaneously (Arousal and Emotion).

Experimental Designs

• Quasi-experimental Design - aims to establish a cause-and-effect relationship between an independent and a dependent variable, similar to a true experiment 

  • Does NOT rely on random assignment of participants to control and treatment groups → participants are often assigned based on non-random criteria or pre-existing group membership 

  • Tends to have lower internal validity but higher external validity 

• Retrospective Cohort Study - a type of observational study that follows a cohort (group) of individuals over time, but the time frame is in the past 

Longitudinal Cohort Study - a type of observation study that follows the same group (cohort) of individuals over an extended period of time