Textbook Outline: Chapters 9-11, 13
❖ Chapter 9: Motivation and Emotion pg 302- 337
■ Motivational Theories
○ Motives are the needs, wants, interests and desires that
propel people in certain directions
○ Motivation involves goal-directed behavior
➢ Drive Theories
○ Homeostasis: a state of physiological equilibrium or
stability
● I.e. a body shivering/sweating to maintain safe
body temperature of 98.6 degrees
○ Drive: a hypothetical, internal state of tension that
motivates an organism to engage in activities that should
reduce this tension
● When individuals experience a drive, they’re
motivated to pursue actions that will lead to drive
reduction
● When you are hungry the discomfort of an empty
stomach is the tension or drive that motivates you
to obtain food, eating restores equilibrium
○ Drive models emphasize the role of homeostasis
➢ Incentive Theories
○ Incentive: an external goal that has the capacity to
motivate behavior
○ Drive is a push theory while incentive is a pull
● According the drive theories, motivation lies
within the organism whereas in incentive theories
the motivation lies outside the organism
○ Incentive models emphasize the role of environment
➢ Evolutionary Theories
○ Motives of humans and other species are products of
evolution
○ Natural selection favors behaviors that maximize
reproductive success
, ● Explains motives such as affiliation, achievement,
dominance, aggression and sex drive
○ Motives can be best understood in terms of their adaptive
uses and problem solving
● Dominance increasing mating success
○ Affiliation motive: need for belongingness
● Help with offspring, collaboration in hunting and
gathering, mutual defense, sexual opportunities
○ Biological motives: hunger, thirst, sex
○ Social Motives: needs for achievement, affiliation,
autonomy, dominance and order
○ Most studied motives are that of hunger, sex, and
achievement
➢ Goals: Compare drive, incentive and evolutionary approaches
to understanding motivation
■ The Motivation of Hunger and Eating
➢ Biological Factors in the Regulation of Hunger
○ Brain regulation
● Hunger is controlled in the hypothalamus
➢ Hypothalamus is a tiny structure involved in
a variety of biological needs related to
survival located in the center of the brain
● 40s/50s theory
➢ Lateral hypothalamus: regulates the desire to
eat
➢ Ventromedial nucleus of the hypothalamus:
controls the ability to recognize satiety
(fullness)
● Current Thinking
➢ Arcuate nucleus and the paraventricular
nucleus modulate hunger
● Contemporary Theories
➢ Focus on neural circuits through the
hypothalamus that depend on a large variety
of neurotransmitters rather than anatomical
, centers
○ Digestive and Hormonal Regulation
● The stomach can send signals to the brain that
inhibit further eating
➢ Vagus nerve: stretching of stomach
➢ Other nerves send satiety messages
depending on the nutrients in stomach
content
● Hormones in bloodstream
➢ Ghrelin: secreted by stomach causing
contractions and promotes hunger when the
body goes without food
➢ CCK: secreted by upper intestine, delivers
satiety signals to the brain reducing hunger
➢ Leptin: produced by fat cells, released in
bloodstream to regulate hunger on a long-
term basis by providing the hypothalamus
with information about the body’s fat stores
➢ Insulin: secreted by the pancreas also senses
fat fluctuations
➢ Environmental Factors in the Regulation of Hunger
○ Food Availability and Related Cues
➢ Humans and other animals are often
motivated to eat for the pleasure of eating
● Palatability: the better food tastes, the more of it
people consume
● Quantity available: people tend to consume what is
in front of them. Larger plate and more selection
causes one to eat more food
● Variety: increase of consumption when a greater
variety of foods are available
➢ Sensory-specific satiety: as you eat a
specific food, its incentive value declines.
The more foods available, the more people
eat
, ● Presence of others: the more people present, the
more people tend to eat
● Stress: half of people increase eating during stress
and many people find a shift towards less healthy
food choices
● Exposure to food cues: food advertisements incites
hunger and leads to increased food intake
○ Learned Preferences and Habits
● Food preferences are influenced by culture and
acquired through learning
● Classical conditioning: learned taste preferences
● Observational learning: eating habits
➢ Eating and Weight: The Roots of Obesity
○ Obesity: the condition of being overweight
● Assessed in terms of BMI (weight/height
squared ...kg/m^2)
● BMI over 30 is considered obese
● Many theorists maintain that the increase of
obesity is due to modern society’s environment
filled with tasty, tempting food everywhere and in
increase and excess of calories
● Health problems include coronary disease, stroke,
hypertension, diabetes, respiratory problems,
gallbladder disease, arthritis, muscle and skeletal
pain, sleep apnea and some types of cancer
○ Genetic Predisposition
● Twin studies have found that identical twins raised
separately have a much similar BMI than fraternal
twins raised together
○ Excessive Eating and Inadequate Exercise
● Overweight people eat too much in relation to their
level of exercise
● Rise of obesogenic environment t the same time as
a decline in physical activity
➢ Convenience: fast foods and elevators