Physiological Psychology: Chapter 10

Question 1

Taste

Answer 1

• Taste affected by hunger; altered by how hungry you are. Taste perception is heightened.

Question 2

Brain Involvement in Eating

Answer 2

• All lobes are used.
• Taste - Frontal lobe; Gustatory cortex
• Smell - Olfactory bulbs
• Texture - Parietal lobe; Crispy vs. Soggy potato chips. Texture may be related to culture
• Visual - occipital and temporal (What something is, memory recall); Food has to be visually appealing. If it is green, it shouldn’t be eaten, etc.

Question 3

Intragastric Feeding

Answer 3

• Tube into the stomach. Chewing is not involved. Controls intake, etc.
• Mouth factors are not enough

Question 4

Stomach Factors

Answer 4

• Distention (getting bigger)
• Speedy signal
• Sent to the brain by the vagus nerve
• Splanchnic nerve
• Ghrelin
• Gastric Bypass

Question 5

Vagus Nerve

Answer 5

• Transmits satiety (fullness, satiation) information to the brain

Question 6

Splanchnic Nerve

Answer 6

• Transmits nutrient content information to the brain

Question 7

Ghrelin

Answer 7

• Secreted in the fasting phase.

* Turns on hunger

Question 8

Gastric Bypass

Answer 8

• Bypass a portion of the stomach and goes directly to the small intestine
• It can work, but there can also be very severe complications

Question 9

Duodenum Factors

Answer 9

• Distention information goes to brain

* Hormone cholecystokinin (CCK) released

Question 10

Cholecystokinin

Answer 10

• Closing sphincter causing stomach to fill faster
• Stimulates vagus nerve to transmit to brain
• Turns off hunger in the brain
• Anorexigenic substance
• Bulimics have lower levels of CCK
• CCK diet drugs generally do not work or change eating or exercising behaviors

Question 11

Pancreatic Hormones

Answer 11

• Glucogen
• Insulin
• Leptin

Question 12

Glucogen

Answer 12

• Stimulates liver to convert glycogen to glucose

* Increasing glucose in bloodstream

Question 13

Insulin

Answer 13

• Helps glucose enter cells. Insulin has to be present so the glucose can be taken up by cells
• Highest levels during absorptive phase
• Decreases glucose in the bloodstream

Question 14

Leptin

Answer 14

• Secreted by fat cells
• Provides information about fat reserves
• Release of leptin turns off eating (anorexigenic)

Question 15

Leptin Diet Drugs

Answer 15

• Most obese individuals already have high levels of leptin. Leptin pills will not help
• Increasing leptin does not affect eating

Question 16

Prolonged Levels of High Insulin

Answer 16

• Glucose enters cells, but stored not used for immediate fuel
• Hunger returns quickly
• Eating increases resulting in weight gain
• Obese have higher insulin level and the body may become less sensitive to insulin

Question 17

Prolonged Low Levels of Insulin

Answer 17

• e.g. diabetes
• Glucose does not enter cell, it is not used for immediate fuel and it is not stored
• Glucose excreted in urine
• Always hungry, but losing weight

Question 18

Arcuate Nucleus Hypothalamus

Answer 18

• Command center
• Getting hunger and satiety signals from the periphery
• Sending that information to other areas of the hypothalamus

Question 19

Lateral Hypothalamus

Answer 19

• Hunger center
• When it is stimulated and it fires, it produces hunger
• Turns on eating
• Controls insulin section, alters taste response, reinforcing nature of food

Question 20

Damage to Lateral Hypothalamus

Answer 20

• Animal refuses food and water as if distasteful

* May starve to death unless force fed

Question 21

Ventromedial Hypothalamus

Answer 21

• Satiety center

* Stimulation gives the feeling of being full

Question 22

Damage to the Ventromedial Hypothalamus

Answer 22

• Overeating and weight gain: Due to eating more frequently than normal; not binge eating, just more meals.
• Stomach motility and secretions increase so it empties faster than normal. Distention will not occur.
• Increase in insulin production; more glucose stored as fat
cells are starving, increase in hunger.

Question 23

Paraventricular Nucleus

Answer 23

• Around the ventricle in the hypothalamus.

Question 24

Damage to Paraventricular Nucleus

Answer 24

• Eats larger than normal meals as if insensitive to usual signals to end meal.

Question 25

Anorexia Nervosa

Answer 25

* Fear of becoming fat or losing self-control resulting in severe decrease of food intake and weight loss. * Symptoms associated with Anorexia Nervosa may be a direct result of starvation. * A study took normal men, had them keep a food diary. The experimenters cut the men's caloric intake by 50% and they began to exhibit the symptoms associated with anorexia. * Cause/Effect?: Alterations in many neurotransmitters, hormones, and neuropeptides.

Question 26

Symptoms of Anorexia Nervosa

Answer 26

* Mood swings * Depression * Obsessive compulsive; Obsessive thoughts, compulsive behaviors * Food hoarding; hiding it in various places * Increased activity, excessive exercise * Insomnia * Decreased body temperature * Hair, muscle and bone loss

Question 27

Drug Treatment for Anorexia Nervosa

Answer 27

* One drug does not affect all aspects * Increase substances that turn on eating; Does not work because it is not a lack of hunger, and by making them feel hungrier, they feel as though they have controlled it more. * Antidepressants — SSRI's: Generally ineffective in promoting weight gain. Somewhat effective in promoting relapse. * Antipsychotics — Chlorpromazine: Somewhat effective in reducing obsessive compulsive aspects.

Question 28

Bulimia

Answer 28

* Binging/overeating huge meals, most times followed by purging. * Different from anorexia — not underweight * May be similar mechanism to drug addiction: Dopamine released during purging. Binging stimulates reinforcement centers. * Higher levels of NPY and Ghrelin (orexigenic). * Lower levels of CCK and serotonin (anorexigenic). * SSRI's (Prozac) sometimes effective in treating Bulimia.