540 likes | 554 Views
This chapter explores the various types of motives, with a focus on hunger and eating behavior. It discusses the role of the hypothalamus and key substances in regulating hunger, as well as the impact of external eating cues. The chapter also covers behavioral dieting, taste aversion, and eating disorders.
E N D
Chapter 12 Motivation and Emotion
Defining Motivation, and a Model • Dynamics of behavior that initiate, sustain, direct, and terminate actions • Model of how motivated activities work • Need: Internal deficiency; causes drive • Drive: Energized motivational state (e.g., hunger, thirst; activates a response) • Response: Action or series of actions designed to attain a goal • Goal: Target of motivated behavior
Types of Motives • Incentive Value: Goal’s appeal beyond its ability to fill a need • Primary Motive: Innate (inborn) motives based on biological needs that must be met to survive • Stimulus Motive: Needs for stimulation and information; appear to be innate, but not necessary for survival • Secondary Motive: Based on learned needs, drives, and goals
Hunger • Homeostasis: Body equilibrium; balance • Hypoglycemia: Low blood sugar • Hypothalamus: Brain structure; regulates many aspects of motivation and emotion, including hunger, thirst, and sexual behavior • Feeding System: Area in the hypothalamus that, when stimulated, initiates eating • Satiety System: Area in the hypothalamus that terminates eating
Fig. 12.1 Needs and incentives interact to determine drive strength (above). (a) Moderate need combined with a high-incentive goal produces a strong drive. (b) Even when a strong need exists, drive strength may be moderate if a goal’s incentive value is low. It is important to remember, however, that incentive value lies “in the eye of the beholder.”
Fig. 12.2 In Cannon’s early study of hunger, a simple apparatus was used to simultaneously record hunger pangs and stomach contractions. (After Cannon, 1934.)
More on Eating Behavior (Hungry Yet?) • Neuropeptide Y (NPY): Substance in the brain that initiates eating • Glucagon-like Peptide 1 (GLP-1): Substance in brain that terminates eating • Set Point: Proportion of body fat that is maintained by changes in hunger and eating; point where weight stays the same when you make no effort to gain or lose weight
Fig. 12.4 This is a cross section through the middle of the brain (viewed from the front of the brain). Indicated areas of the hypothalamus are associated with hunger and the regulation of body weight.
The Final Word on Eating Behavior • Leptin: Substance released by fat cells that inhibits eating; presently being studied for possible importance in controlling and losing weight • External Eating Cues: External stimuli that tend to encourage hunger or elicit eating; these cues may cause you to eat even if you are stuffed (like Homer Simpson, who eats whatever he sees!)
Behavioral Dieting • Weight reduction based on changing exercise and eating habits and not on temporary self-starvation • Some keys • Start with a complete physical • Exercise • Be committed to weight loss
Behavioral Dieting (cont.) • Observe yourself, keep an eating diary, and keep a chart of daily progress • Eat based on hunger, not on taste or learned habits that tell you to always clean your plate • Avoid snacks • Learn to weaken personal eating cues
Taste • Taste Aversion: Active dislike for a particular food • VERY difficult to overcome • Bait Shyness: Unwillingness or hesitation by animals to eat a particular food
Eating Disorders: Anorexia Nervosa • Active self-starvation or sustained loss of appetite that seems to have psychological origins • Control issues seem to be involved • Very difficult to effectively treat • Affects adolescent females overwhelmingly
Fig. 12.6 Women with abnormal eating habits were asked to rate their body shape on a scale similar to the one you see here. As a group, they chose ideal figures much thinner than what they thought their current weights were. (Most women say they want to be thinner than they currently are, but to a lesser degree than women with eating problems.) Notice that the women with eating problems chose an ideal weight that was even thinner than what they thought men prefer. This is not typical of most women. In this study, only women with eating problems wanted to be thinner than what they thought men find attractive (Zellner, Harner, & Adler, 1989).
Eating Disorders: Bulimia Nervosa (Binge-Purge Syndrome) • Excessive eating usually followed by self-induced vomiting and/or taking laxatives • Difficult to treat • Prozac approved by FDA to treat bulimia nervosa • Affects females overwhelmingly
Causes of Anorexia Nervosa and Bulimia Nervosa • Anorectics and bulimics have exaggerated fears of becoming fat; they think they are fat when the opposite is true! • Bulimics are obsessed with food and weight; anorectics with perfect control • Anorectics will often be put on a “weight-gain” diet to restore weight
Thirst and Pain • Extracellular Thirst: When water is lost from fluids surrounding the cells of the body • Intracellular Thirst: When fluid is drawn out of cells because of increased concentration of salts and minerals outside the cell • Best satisfied by drinking water • Pain Avoidance: An episodic drive • Occurs in distinct episodes when bodily damage takes place or is about to occur
Sex Drive • Estrus: Changes in animals that create a desire for sex; females in heat • Estrogen: A female sex hormone • Androgens: Male hormones • Non-homeostatic: Independent of bodily need states
Stimulus Drives • Reflect needs for information, exploration, manipulation, and sensory input • Yerkes-Dodson Law: If a task is simple, it is best for arousal to be high; if it is complex, lower levels of arousal provide for the best performance • Arousal Theory: Ideal levels of activation occur for various activities • Arousal: Activation of the body and nervous system • Sensation Seeking: Trait of people who prefer high levels of stimulation (e.g., the contestants on “Eco-Challenge” and “Fear Factor”)
Fig. 12.7 Monkeys happily open locks that are placed in their cage. Since no reward is given for this activity, it provides evidence for the existence of stimulus needs. (Photo courtesy of Harry F. Harlow.)
Fig. 12.8 (a) The general relationship between arousal and efficiency can be described by an inverted U curve. The optimal level of arousal or motivation is higher for a simple task (b) than for a complex task (c).
How to Cope With Test Anxiety • Preparation • Relaxation • Rehearsal • Restructuring thoughts
Circadian Rhythms • Cyclical changes in bodily functions and arousal levels that vary on a 24 hour schedule • Preadaptation: Gradual matching of sleep-waking cycles to a new time schedule before an anticipated circadian rhythm change • E.g. trying to adjust to new time zone to avoid jet lag • Melatonin: Hormone produced by pineal gland in response to light (production suppressed) and dark (production increased)
Fig. 12.9 Core body temperature is a good indicator of a person’s circadian rhythm. Most people reach a low point 2 to 3 hours before their normal waking time. It’s no wonder that both the Chernobyl and three-Mile Island nuclear power plant accidents occurred around 4 am. Rapid travel to a different time zone, shift work, depression, and illness can throw sleep and waking patterns out of synchronization with the body’s core rhythm. Mismatches of this kind are very disruptive (Hauri & Linde, 1990).
Jet Lag • Disturbed body rhythms caused by rapid travel east or west • Major time shifts (5 hours or more) can cause very slow adaptation • Direction of travel affects adaptation, and thus, severity of jet lag • MUCH easier to go east to west than west to east • Preadaptation: Gradual matching of sleep-waking cycles to a new time schedule
Fig. 12.10 Time required to adjust to air travel across six time zones. The average time to resynchronize was shorter for westbound travel than for eastbound flights. (Data from Beljan et al., 1972; cited by Moore-Ede et al., 1982).
Learned Motives • Opponent Process Theory: Strong emotions tend to be followed by an opposite state; strength of both emotional states over time • Social Motives: Acquired by growing up in a particular society or culture • Need for Achievement: Desire to meet some internal standard of excellence • Need for Power: Desire to have social impact or control over others
Abraham Maslow and Needs • Hierarchy of Human Needs: Maslow’s ordering of needs based on presumed strength or potency; some needs are more powerful than others and thus will influence your behavior to a greater degree • Basic Needs: First four levels of needs in Maslow’s hierarchy • Lower needs tend to be more potent (“prepotent”) than higher needs • Growth Needs: Higher-level needs associated with self-actualization • Meta-Needs: Needs associated with impulses for self-actualization
Fig. 12.12 Maslow believed that lower needs in the hierarchy are dominant. Basic needs must be satisfied before growth motives are fully expressed. Desires for self-actualization are reflected in various meta-needs.
Types of Motivation • Intrinsic Motivation: Motivation coming from within, not from external rewards; based on personal enjoyment of a task • Extrinsic Motivation: Based on obvious external rewards, obligations, or similar factors
Emotions • State characterized by physiological arousal and changes in facial expressions, gestures, posture, and subjective feelings • Adaptive Behaviors: Aid our attempts to survive and adjust to changing conditions • Physiological Changes: Include heart rate, blood pressure, perspiration, and other bodily responses
More Emotions • Adrenaline: Hormone produced by adrenal glands that arouses the body • Emotional Expression: Outward signs of what a person is feeling • Emotional Feelings: Private emotional experience
Primary Emotions and Mood • Eight primary emotions (Plutchik, 2001) • Fear • Surprise • Sadness • Disgust
Primary Emotions and Mood (cont.) • Anger • Anticipation • Joy • Trust • Mood: Low-intensity, long-lasting emotional state
Fig. 12.13 Primary and mixed emotions. In Robert Plutchik’s model there are eight primary emotions, as listed in the inner areas. Adjacent emotions may combine to give the emotions listed around the perimeter. Mixtures involving more widely separated emotions are also possible. For example, fear plus anticipation produces anxiety. (Adapted from Plutchik, 2001.)
Brain and Emotion • Amygdala: Part of limbic system that produces fear responses • Autonomic Nervous System (ANS): Neural system that connects brain with internal organs and glands • Sympathetic Branch: Part of ANS that activates body for emergency action • Parasympathetic Branch: Part of ANS that quiets body and conserves energy • Parasympathetic Rebound: Overreaction to intense emotion
Fig. 12.15 An amygdala can be found buried within the temporal lobes on each side of the brain. The amygdala appears to provide “quick and dirty” processing of emotional stimuli that allows us to act involuntarily to danger.
Lie Detectors • Polygraph: Device that records heart rate, blood pressure, respiration, and galvanic skin response (GSR); lie detector • GSR: Measures sweating • Irrelevant Questions: Neutral, nonthreatening, non-emotional questions in a polygraph test • Relevant Questions: Questions to which only someone guilty should react • Control Questions: Questions that almost always provoke anxiety in a polygraph (e.g. “Have you ever taken any office supplies?”)
Fig. 12.17 A typical polygraph includes devices for measuring heart rate, blood pressure, respiration, and galvanic skin response. Pens mounted on the top of the machine make a record of bodily responses on a moving strip of paper. (right) Changes in the area marked by the arrow indicate emotional arousal. If such responses appear when a person answers a question, he or she may be lying, but other causes of arousal are also possible.
Body Language (Kinesics) • Study of communication through body movement, posture, gestures, and facial expressions • Emotional Tone: Underlying emotional state • Facial Blends: Mix of two or more basic expressions
Three Types of Facial Expressions • Pleasantness-Unpleasantness: Degree to which a person is experiencing pleasure or displeasure • Attention-Rejection: Degree of attention given to a person or object • Activation: Degree of arousal a person is experiencing
Fig. 12.18 When shown groups of simplified faces (without labels) the angry and scheming faces “jumped out” at people faster than sad, happy, or neutral faces. An ability to rapidly detect threatening expressions probably helped our ancestors survive (adapted from Tipples, Atkinson & Young, 2002).
Detecting Lies • Illustrators: Gestures people use to illustrate what they are saying • Emblems: Gestures that have widely understood meanings within a particular culture
Theories of Emotion • James-Lange Theory: Emotional feelings follow bodily arousal and come from awareness of such arousal • Cannon-Bard Theory: The thalamus (in brain) causes emotional feelings and bodily arousal at the same time • Schachter’s Cognitive Theory: Emotions occur when a label is applied to general physical arousal • Attribution: Mental process of assigning causes to events; attributing arousal to a certain source • Facial Feedback Hypothesis: Sensations from facial expressions and becoming aware of them is what leads to the emotion someone feels
A Modern View of Emotion • Emotional Appraisal: Evaluating personal meaning of a stimulus • Emotional Intelligence: Combination of skills, including empathy, self-control, and self-awareness; includes: • Self-awareness • Empathy • Managing, understanding, and using emotions