11.1 | Hunger and Eating Flashcards Preview

• motivation: the physiological and psychological processes underlying the initiation of behaviours that direct organisms toward specific goals
• includes the physiological and psychological processes underlying the initiation of behaviours that direct organisms toward specific goals

• drive: a biological trigger that tells us we may be deprived so something and causes us to seek out what is needed such as food and water
• when a drive is satisfied, reward centers in our brains become activated and reinforces our behaviour

• homeostasis: the body’s physiological processes that allow it to maintain consistent internal states in response to the outer environment

• allostasis: motivation is not only influenced by current needs, but also the anticipation of future needs
• e.g. eating a lot of food when anxious

• cause can be found in the hypothalamus; a set of "on" and "off" switches on the bottom surface of the brain
• glucose: a sugar that serves as a primary energy source for the brain and the rest of the body
• when glucose levels are too low, the hypothalamus detects this which causes hunger
• insulin stores glucose, which lowers glucose levels and the cycle begins again
• satiation: the point in a meal when we're no longer motivated to eat

• humans learned that the best strategy was to “eat while you can” because there was no guarantee that another meal would be coming any time soon
• over the course of evolution, our bodies responded to this need with a number of systems that made the consumption of high-energy foods pleasurable
• we crave fats because we have specialized receptors on the tongue that are sensitive to the fat content of food
• sugar and some addictive drugs can stimulate release of dopamine in the nucleus accumbens, a brain region associated with reinforcing effects of amphetamines and cocaine; sugar can be addictive
• we stress eat because the principle of allostatsis causes us to forsee a stressful event in the future, so it's better if we prepare now

• unit bias: the tendency to assume that the unit of sale or portioning is an appropriate amount to consume 
• e.g. the bottomless bowl of soup; participants who ate 70% more than the control group didn't report feeling more satiated
• e.g. the stale popcorn experiment; those with the large bags ate more, even if the popcorn tasted like cardboard

• whether the presence of other people increases or decreases our motivation to eat is influenced by the social situation 
• social facilitation (eating more): dinner hosts encourage guests to take several helpings; as well, the longer a person sits socializing the more like they are to continue eating
• impression management (eating less): self-conciously controlling behaviour so that others will see them in a certain way; e.g. chewing with your mouth closed is polite
  • minimal eating norm: a social norm indicating that eating smaller portions is more polite
• modelling (eating whatever they eat): e.g. being at a company dinner and not eating too much, then hanging out with your friends and eating a ton even though you're full

• obesity: a disorder of positive energy balance, in which energy intake exceeds energy expenditure 

reasons obesity rates are so high:

• the huge variety of foods available
• we still crave fatty foods due to our evolutionary needs, but nowadays there aren't long periods of time where people go hungry
• the poor are more heavily affected because cheap foods tend to be unhealthy

• anorexia nervosa: an eating disorder that involves (1) self-starvation, (2) intense fear of weight gain and dissatisfaction with one’s body, and (3) a denial of the serious consequences of severely low weight
• bulimia nervosa: an eating disorder that is characterized by periods of food deprivation, binge-eating, and purging
• bulimia tends to be impulsive, whereas anorexia is not
• bulimics tend to find their cyclical patterns disturbing, whereas anorexics seen indifferent to their behaviour
• the most common reason eating disorders develop is stress, and a perceivied loss of control
• those with eating disorders also tend to feel depressed, guilty, have low self-esteem, perfectionism, and/or suppressed anger
• repreoduction suppression hypothesis: females who believe they have low levels of social support from romantic partners and family members are more likely to engage in dieting behaviour; this change in food intake can influence ovulation
• both men and women develop eating disorders