Transcript here - Columbian High School

Unit 8: Motivation and
Emotion
A - Motivation
Four perspectives used to
understand motivation:
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Instinct theory (evolutionary perspective)
Drive-reduction theory
Arousal theory
Maslow’s hierarchy of needs
Instinct Theory
• Unlearned behaviors that organisms are
genetically predisposed to exhibit drive us
• Does apply to species-typical behavior
• Major drawback: this theory describes
motivation but doesn’t explain it
Drive-Reduction Theory
• Inner drives push and external incentives
pull us towards particular behaviors
• Physiological needs (such as for food or
water) create an arousal state that we then
are motivated to correct to reach
homeostasis
• Environmental stimuli also cause us to
seek incentives (operant conditioning)
Arousal Theory
• Boredom may actually cause us to seek
increased arousal (curiosity)
• Everyone has an optimum level of arousal
• Some individuals are motivated because
they have a high need for arousal, others
have a lower need for arousal
• May be affected by brain areas
Maslow’s Hierarchy of Needs
• He argued that the needs build on one
another – we are more likely to be
preoccupied with satisfying lower level
needs before we move to satisfy higher
levels
• But, the order of the needs is not universal
Common human behaviors research seeks
to explain with motivational theories:
• Hunger – obesity, eating disorders
• Sexual motivation
• Need for belongingness – need for
affiliation
Hunger
Physiology of Hunger
- Stomach signals hunger with
contractions (pangs)
- Empty stomach secretes ghrelin –
but even those with no stomach
still feel hungry
- Low blood glucose makes us feel
hungry because it causes the
lateral hypothalamus to produce
orexin
- Ventromedial hypothalamus, PYY,
and leptin depress hunger
- Set point may actually be a
settling point because BMR can
change through calorie
deprivation, exercise
Psychology of Hunger
- Carbs raise serotonin levels,
which calms us
- Genetics – preference for
sweet and salty foods,
avoidance of unfamiliar foods,
taste aversions easily
conditioned
- Environmental influence
evidenced by social facilitation
and unit bias
Eating Disorders
Types
Anorexia nervosa – below
normal body weight (may
also purge)
Bulimia nervosa – binge and
purge
Binge-eating – binge but no
purge
Causes
- Related to low selfesteem, perfectionism,
excessive concern with
other perception of them
- May have a genetic
component
- Culture – body image
ideal, media
- More common among
young females, but
affects males and older
women too
Obesity
• Major health issue in United States – 2/3 overweight and
1/3 obese
• Increased risk of diabetes, high blood pressure, heart
disease, gallstones, arthritis, some cancers, Alzheimer’s
and brain tissue loss (women)
• Shortens life span
• Social effects – weight bias (discrimination), especially
against women
• Psychological effects – associated with lower
psychological well-being and 25% increase in
depression and anxiety
Causes of Obesity
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Fat cells
– We are born with a certain number of fat cells, how many may be genetic
– We will never decrease the number of fat cells but we can increase them with
childhood or adulthood overeating patterns
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Set point and BMR (metabolism)
– Fat requires fewer calories to maintain than lean tissue
– If we cut calories, the body will adapt by burning fewer calories, slowing
metabolism
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Genetics
– Many genes implicated
– Correlation with natural parents weight not adoptive
– Identical twins reared apart have similar weights
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Food and Activity levels
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Lack of sleep related to obesity
More likely to become obese if a friend is obese
Food consumption levels changing – unit bias
Activity levels falling - technology
Losing Weight
• Most who lose weight will regain it
• Must set realistic and moderate goals
• Must modify lifestyle in terms of eating
habits and activity levels
• Obesity probably not caused by guilt,
hostility, oral fixation, lack of willpower, etc.
Sexual Motivation
• Masters and Johnson identified the sexual response cycle
– Excitement, plateau, orgasm, resolution
– Refractory period shorter for women than for men
• Sex hormones (estrogen and testosterone) play a role in
development of primary and secondary sex characteristics
and in sexual behavior
• Females - fluctuation of estrogen levels has some impact on
sexual behavior, but not to the same degree as in animals human female sexual behavior more influenced by
testosterone
• Males - testosterone levels have little effect on sex drive
unless there are large changes
Psychology of Sex
• Sexual behavior is influenced by both
external stimuli and internal (imagined)
stimuli
• Exposure to sexually explicit media
impacts both men and women - may
cause devaluation or dissatisfaction with
current partner
• Sexual fantasies are normal
Adolescent Sexuality
• Major issue due to conflicting feelings - natural feelings
of changes in body due to hormones may conflict with
social, family, personal, religious values about sexual
behavior
• Higher teen pregnancy rates in U.S. compared to Europe
- ignorance, little communication about birth control,
guilt, alcohol use, mass media norms of promiscuity
• STIs (STDs) - 40% of sexually active teens had an STI in
1994
• Predictors of abstinence - high IQ, religious, father in the
home, participation in community service
Sexual Orientation
• Statistics?
– 3 to 4% of men are homosexual
– 1 to 2% of women are homosexual
– Less than 1% are bisexual
• Sexual orientation is not an indicator of
mental health
Origins of homosexuality
Nature
- fraternal birth-order effect
- Same-sex relations in hundreds of species
- Brain differences
- Gay men and straight women have hemispheres of
about same size
- Lesbian women and straight men have larger right
hemispheres
- Genetics seems to play a role
- Prenatal hormone exposure between 2nd and 5th month
- “exotic is erotic”
The Need to Belong (Need for Affiliation)
• Why do we become strongly attached in
enduring relationships?
– From an evolutionary perspective, social
bonds have helped humans survive and
reproduce
– Being in healthy close relationships is
correlated with higher levels of happiness,
better health, and lower risk for psychological
problem and early death
• Fear of being alone is a motivating force causing
us to seek acceptance
• Severe social isolation causes problems in
children
• Ostracism, social exclusion, causes increased
activity in anterior cingulate cortex (this area is
also activated by physical pain)
– May result in depressed mood, withdrawal
– May then seek new friends or turn nasty