PSYC101 Mid3 Review

Behavior genetics

Study of the relative influence of heredity and environment on behavior

Similarity vs distinctiveness

Humans share a common biological heritage and behavioral tendencies, but differences (appearance, sounds, experiences) are more likely to attract attention

Nature's two experiments

Identical twins (100% shared genes) and fraternal twins (~50% shared genes); comparing them separates genetic from environmental influence

Identical (monozygotic) twins

Develop from one fertilized egg that splits; genetically identical

Fraternal (dizygotic) twins

Develop from two separate eggs; share about 50% of genes, like ordinary siblings

Twins reared together (findings)

Identical twins are more alike than fraternal twins in abilities, personality, and many disorders

Twins reared apart (Minnesota study, Bouchard)

Identical twins raised apart are strikingly similar in personality, abilities, attitudes, interests, and fears

"Jim twins"

Anecdotal evidence: separated identical twins with many coincidences (wives Linda then Betty, sons James Alan, dogs named Toy); weak evidence because coincidences are common

Criticisms of twins-reared-apart studies

Twins share appearance, age, and prenatal environment; adoption agencies place children in similar homes

Adoption studies

Compare adoptees with biological (genetic) vs adoptive (environmental) relatives; personality resembles biological parents more

What adoptive parents still influence

Attitudes, values, manners, religious faith, and politics; adoption also improves children's outcomes

Heritability

Proportion of variation among individuals in a group attributable to genes; applies to groups, not individuals

Heritability and environment

The more similar people's environments, the higher heritability; high heritability within groups does NOT explain differences between groups (seed analogy)

Evolutionary psychology

Study of the evolution of behavior and mind using principles of natural selection

Natural selection (Darwin's tenets)

Organisms vary; variations are inherited; more offspring than can survive compete; traits aiding survival and reproduction become more common

Gender differences in sexuality

On average men think about sex more, masturbate more, and are more interested in casual sex and multiple partners

Gender differences in mating preferences

Men prefer youthful, fertile-looking partners; women prefer mature, dominant, affluent, committed partners (Buss, 37 cultures)

Evolutionary explanation of mating preferences

Women invest more in each child, so they choose carefully; men could spread genes widely, so they value fertility cues

Critiques of evolutionary psychology

Hindsight explanations that are hard to falsify; social-role theory (differences shrink with gender equality); evolved does not mean unchangeable

Gender similarity

Men and women are far more alike than different (share 45 of 46 chromosomes; most psychological differences are small)

Physical gender differences

Men taller and more muscular; women more body fat, puberty ~2 years earlier, live ~5 years longer

Psychological gender differences

Men more physical aggression; women more relationally interdependent ('tend and befriend'); women more depression/anxiety, men more alcohol use disorder and antisocial behavior

Social gender differences

Men more often hold social power and lead directively; gender roles are culturally variable expectations

Culture

Shared behaviors, ideas, attitudes, values, and traditions passed from one generation to the next; facilitates survival and reproduction

Collectivism

Priority on group goals; interdependent self; identity from belonging; behavior reflects social norms and roles

Individualism vs collectivism: coping

Individualist: change reality; collectivist: accommodate to reality

Individualism vs collectivism: relationships

Individualist: many, often temporary, confrontation acceptable; collectivist: few, close and enduring, harmony valued

Motivation

The energization and direction of behavior (what gets behavior going and points it toward a goal)

Instinct

Complex, unlearned, fixed behavior pattern shown by all members of a species

Instinct theory (William McDougall, 1908)

Behavior is driven by innate instincts; abandoned because it named behaviors instead of explaining them (circular) and the lists of instincts ballooned

Evolutionary psychology (motivation)

Modern version of instinct theory: genes predispose adaptive, species-typical behaviors (e.g., fear of snakes, liking sweets)

Drive-reduction theory (Clark Hull, 1943)

Physiological need → drive (aroused tension) → drive-reducing behavior → homeostasis; motivation as a 'push'

Primary vs secondary drives

Primary = biological (hunger, thirst); secondary = learned (money, approval)

Arousal theory

People seek an optimal level of arousal: seek stimulation when bored, calm when overwhelmed

Incentive theory

Behavior is 'pulled' by external rewards or goals (incentives) rather than pushed by internal drives

Intrinsic vs extrinsic motivation

Intrinsic = doing it for its own sake; extrinsic = doing it for an outside reward or to avoid punishment

Abraham Maslow

Humanistic psychologist who proposed the hierarchy of needs (1943)

Maslow's hierarchy (bottom → top)

Physiological → Safety → Belongingness/love (social) → Esteem → Self-actualization → Self-transcendence

Physiological needs

Need to satisfy hunger and thirst (base of Maslow's pyramid)

Safety needs

Need to feel the world is organized and predictable; need to feel safe

Belongingness and love needs

Need to love and be loved, to belong and be accepted; avoid loneliness and separation

Esteem needs

Need for self-esteem, achievement, competence, independence, and recognition/respect from others

Self-actualization

Need to live up to our fullest and unique potential

Self-transcendence

Need to find meaning and identity beyond the self (top of Maslow's revised pyramid)

Criticisms of Maslow

Order isn't universal (people pursue higher needs while lower ones are unmet), reflects individualistic Western values, hard to test

Cannon & Washburn (1912)

Washburn swallowed a balloon; stomach contractions coincided with hunger pangs. But people without stomachs still feel hungry

Insulin

Pancreatic hormone that controls blood glucose

Set point

Weight the body tries to maintain by adjusting hunger and metabolic rate

Basal metabolic rate

The body's resting rate of energy expenditure

Psychological influences on hunger

Taste preferences (sweet/salty, culture, neophobia), external cues (sight, smell, time, portion size, variety), social cues (eating more with others)

Anorexia nervosa

Severe food restriction, intense fear of weight gain, distorted body image; significantly low weight; highest mortality of psychiatric disorders

Bulimia nervosa

Recurrent binge eating followed by compensatory behavior (vomiting, laxatives, fasting, excessive exercise); usually normal weight

Binge-eating disorder

Recurrent binges with distress/guilt but NO compensatory behavior; most common eating disorder

Potential causes of eating disorders

Genetics (twin concordance), sociocultural thin ideal, perfectionism/low self-esteem, family pressure

Sexual response cycle (order)

Excitement → Plateau → Orgasm → Resolution

Refractory period

Resting period after male orgasm (during resolution) when another orgasm is not possible

Estrogen

Female sex hormone; drives estrus in many non-human animals; weaker effect on human desire

Testosterone

Sex hormone in both sexes (more in males); linked to sexual interest in men and women

Hormones and human sexual behavior

Hormones influence but don't dictate human sexual behavior; external and imagined stimuli, culture, and relationships matter

Origins of sexual orientation

Psychological/parenting theories unsupported; biological evidence: LeVay's hypothalamus finding, twin studies, prenatal hormones, fraternal birth-order effect

Baumeister & Leary (1995)

Need to belong: a fundamental human motive to form and maintain lasting, positive relationships

Why we are social animals

Belonging aided ancestral survival (protection, food sharing, child-rearing); humans are naturally oriented toward others

Need for affiliation

Desire to be with others and have friendly social contact; benefits include social support and reduced anxiety

Need for intimacy

Desire for warm, close, communicative relationships (self-disclosure, mutual concern); linked to well-being

Need for achievement (David McClelland, 1953)

A strong desire to accomplish difficult tasks, outperform others, and excel

Correlates of high need for achievement

Prefer moderately difficult tasks, persist longer, seek feedback, credit effort; parents encouraged independence

Thematic Apperception Test (TAT)

Measures motives (achievement, affiliation, power) by scoring stories people tell about ambiguous pictures

Need for power (David Winter, 1973)

A strong desire to acquire prestige and influence over others

Amy Wrzesniewski

Researcher who identified three work orientations: job, career, calling

Job orientation

Work is a necessity to earn money; focus on pay and benefits

Career orientation

Work is a path of advancement; focus on promotion and prestige

Calling orientation

Work is fulfilling and meaningful in itself; highest job and life satisfaction

Flow (Mihaly Csikszentmihalyi)

Completely absorbed, focused state with lost sense of self and time; occurs when challenge matches skill

Emotion (three components)

1) Internal physiological arousal, 2) expressive behavior in face and body, 3) cognitive appraisal (conscious experience)

Why emotion is a construct

It can't be observed directly; it must be inferred from reports, bodily responses, and behavior, so it is hard to define

Common-sense view of emotion

Stimulus → emotion → bodily arousal (I see a bear, feel afraid, then my heart pounds)

James-Lange theory

Stimulus → bodily arousal → emotion; emotion is our awareness of physiological responses ('afraid because we tremble')

Cannon-Bard theory (1927)

Stimulus triggers arousal and emotion simultaneously and independently (via the thalamus)

Sympathetic nervous system

Arouses the body (fight or flight): faster heart, higher BP, pupils dilate, digestion slows, sweating

Parasympathetic nervous system

Calms the body after arousal

Limbic system (emotion)

Brain circuitry for emotion, incl. amygdala (fear), hypothalamus (arousal), hippocampus (emotional memory)

Charles Darwin (1872)

The Expression of the Emotions in Man and Animals: facial expressions evolved, are innate and universal

Paul Ekman

Showed facial expressions are recognized universally, incl. by the isolated Fore people of New Guinea

Six basic emotions (Ekman)

Happiness, surprise, fear, sadness, anger, disgust

Carroll Izard

Studied infants' facial expressions; distinct expressions appear early, supporting an innate basis

Infant emotions (Izard)

Joy, anger, interest, disgust, surprise, sadness, fear

Survival value of recognizing emotion

Quickly reading faces helps detect threats, avoid danger/contamination, and coordinate with others

Body language

Posture, gestures, gaze, and tone communicate emotion; many gestures are culture-specific

Facial-feedback hypothesis

Facial expressions can intensify or produce the corresponding emotion

Schachter's two-factor theory

Emotion = physiological arousal + cognitive label; the label determines which emotion we feel

Schachter & Singer (1962)

Epinephrine-injected participants who were uninformed about its effects adopted a confederate's euphoria or anger; informed participants did not

Misattribution of arousal

Attributing arousal to the wrong source

Dutton & Aron (1974)

Men on a scary suspension bridge were more likely to call a female interviewer than men on a stable bridge; misattributed fear as attraction

Subjective well-being

Self-perceived happiness or satisfaction with life

Levels of happiness

Most people report being moderately to fairly happy

Correlates of happiness (strong)

Close relationships, optimism/extraversion, high self-esteem, meaningful work, religious faith, good sleep and exercise

Factors weakly related to happiness

Age, gender, parenthood, physical attractiveness, education level

Roots of happiness

Genes (twin studies, e.g., Lykken & Tellegen 1996), personal history and choices, culture

Money and happiness (U.S. 1957-2005 graph)

Income roughly tripled but % 'very happy' stayed flat (~30-35%); money matters mainly up to meeting basic needs

Social-comparison theory

We judge our well-being relative to others; comparing to richer people cancels gains (relative deprivation)