Chapter 7: The Feeling Mind- Motivation and Emotion- Motivation and emotion involve neural circuits that operate below the level of our conscious awarenessHow are Motivation and Emotion related?- Both share the experience of subjective feelings and engage similar processes and structures in the brain- Emotion- A combination of arousal, physical sensations, and subjective feelings that occurs spontaneously in response to environmental stimulio Spontaneous, automatic responses to situationso Communicate through facial expression, body language, gestures, and tone of voice- Mood- more general state than an emotion and lasts longer- Motivation- a process that arouses, maintains, and guides behavior toward a goal- Motivation and emotion share ability to arouse an organism and stimulate behavior- But motivation dos so more in a direct and precise fashion than emotionsWhat does it mean to be motivated?- Motivational systems allow an animal to be aroused only when necessary, such as when it needs food, and then reduces arousal following the solution of a problem- Homeostasis- a steady internal balance, or equilibrium- Set points- a value that is defended to maintain homeostasis- Deviations from these set points stimulate behavior by the organism that is designedto reestablish the original values- Core body temp- 98.6 degrees F (37C)- Motivation begins with a stimulus, from either the internal or external environment of the organism, that serves as a cue for motivated behavior- Drive- a state of tension and arousal triggered by cues important for survivalo Propels the organism into some sort of action related to stimulus- Drive reduction- the state of relief and reward produced by removing the tension and arousal of the drive state- Drive theories = push theories “pushing an organism toward a goal”- Incentives- a reward that pulls an organism’s behavior in a particular directiono Intrinsic rewards- a reward that arises internally Feeling of accomplishment when goal is meto Extrinsic reward- a reward from an outside source Money or praise Sometimes have negative effects on intrinsic motivationHunger and Eating- The reduction of hunger through eating is influenced by emotion, learning, and cultureThe Sensation of Hunger- External cues for hungero Time of dayo Sights and smells of foodso Admonitions that we should clean our plateso Social settingo Encourage us to eat when our bodies don’t need nutrients- Internal cues for hungero When our bodies are genuinely short on nutrientso Stomach contractionso Low level of circulating sugarso Glucose- a type of sugar that plays an important role in hunger levels Glucose [] in blood are highest following a meal Intimately connected with levels of hormone insulino Insulin- hormone released by pancreaso Glucose and insulin are positively correlated- Diabetes- high levels of glucose can harm many organso High levels occur in untreated diabetes due to either a lack of insulin production (type I) or body’s resistance to insulin (type II)o Without sufficient insulin, circulating glucose in unable to move out of the blood into the cells that need nutrients- Hunger will result whenever cells are unable to obtain the glucose they require- Hunger occurs in response to low levels of stored fats- If you maintain a healthy weight, you are carrying sufficient body fat to survive five to six weeks of total starvation.- Leptin- a hormone secreted by fat cells that helps the body maintain an appropriate level of stored fato Fat stores and leptin are positively correlatedo When leptin levels are low, brain areas like the lateral hypothalamus initiate feedingo Stimulation of the LH typically initiates immediate eating- Low fat stores and leptin levels activate the parasympathetic division of the autonomic nervous system, enhancing the body’s ability to digest and store nutrients- Metabolism- the chemical reactions required by life- Activation of the parasympathetic nervous system, initiation of feeding behavior andreduction in metabolic rate allow the animal to find, eat, and store nutrients- As fat stores return to normal, leptin increases and the feeding cycle tempers off.- Ghrelin- hormone that stimulates feeding released by the pancreas and the lining of the stomacho Contributes to the rewarding aspects of feeding- Orexins- produced in the LHo Participate in sleep, suggesting that they might link feeding, activity levels, and sleepThe Sensation of Satiety- Satiety- the sense of feeling full; not requiring further food- Reach satiety before nutrients we have eaten make it to our cells- The ventromedial hypothalamus participates in sensing satiety- VMH lesions are boosts in insulin production, which in turn produce low blood glucose levels and hunger- Cholecystokinin- gut hormone released by the digestive system to response to the arrival of foodo Contributes to feelings of satietyo Not only acts in digestive tract but also chemical messenger in braino Normally acts to inhibit further eating- As time without food progresses, fat levels drop, leptin levels drop, and the feeding sequence is initiated again- Injections of leptin allowed mice to lose weighto Not true in humansObesity- Body Mass Index (BMI)- a height-to-weight ratio used to identify healthy weight, underweight, overweight and obesityo Divide weight in kilograms by the square of height in meterso Scores 18.5 and 24.9 are healthyo 25-30 is overweighto Above 30 is obese- Genetic predispositions, lifestyle issues, and social comparisons all make significant contributions to obesity- Genes can influence factors such as set point and rate of metabolism- A cultural contribution to obesity is our sedentary lifestyle- To avoid starvation, our ancestors developed strong preferences for calorie-rich foods containing sugars and fats- Successful diets should be viewed as lifestyle changes that are sustainable for an individual- In the ‘50’s and ‘60’s doctors prescribed amphetamines for weight loss o They suppress appetite but are addictive and psychoactive- Stomach stapling and gastric bypass reduce the amount of nutrients that can be consumed or processedAnorexia Nervosa and Bulimia Nervosa- People with this have a distorted body image; they see themselves as obese when they are in fact in danger of starvation- ¼ are men- Muscle dysmorphia- a body distortion problem where men see themselves as weak even if they work out all the time- Anorexia nervosa- an eating disorder