Motivation (Ch 11) Flashcards
Motivation
- defined as the urge to move toward one’s goals, whatever they may be
- needs, drives, and incentives all contribute to motivation
Needs
- states of cellular or bodily deficiency that compel drives
- inherited biologically
- water, food, oxygen
Drives
- the perceived states of tension that occur when our bodies are deficient in some need
- such a deficiency creates a drive (thirst or hunger) to alleviate the state
Incentive
-any external object or event that motivates behaviour
Evolutionary model
- the purpose of any living organism is to perpetuate itself
- process of natural and sexual selection have shaped motivation over time to make all animals want things to help them survive and reproduce
Instinct
- an inherited behavioural tendency of a species
- implies internal drives are constant amongst members of a species because they serve adaptive functions for survival
Drive reduction model
-when our physiological systems are out of balance or depleted, we are driven to reduce this depleted state
Homeostasis
- central to drive reduction is the idea of maintaining physiological balance (homeostasis)
- all organisms are motivated to maintain physiological equilibrium around an optimal set point
- sensory detectors trigger mechanisms that motivate us to take action
- homeostasis describes the feedback look
Set point
-ideal fixed setting of a particular physiological system
Optimal arousal
- proposes that we function best at an optimal level of arousal
- research by Yerkes and Dodson shows that low arousal and high arousal lead to poor performance
- after long periods of sensory deprivation, people begin to hallucinate, their cognitive ability and concentration suffer, and they develop childish emotional responses
Flow
-termed used in 1990s to describe the fact that people perform best and are most creative when they are optimally challenged relative to their abilities
Hierarchical model
-combines drives and incentives
-needs range from the most basic physiological necessities to the highest, most physiological needs for growth and fulfilment.
Top:
Parenting
Mate retention
Mate acquisition
Status/esteem
Affiliation
Self-protection
Immediate physiological needs
Hunger
- hunger has 4 components: blood, stomach, brain, and hormones/neuro chemicals
- contraction of stomach occurs when it and small bowel have been empty for about 2 hours
- contractions don’t CAUSE hunger
Glucose
- most important source of energy for the body
- simple sugar that provides energy for cells throughout the body, including the brain
- blood sugar drops when we go without eating for long periods
- hypothalamus monitors this and triggers hunger when it drops too low
Hypothalamus
- regulates most basic physiological needs
- unique in that certain regions lack an effective blood brain barrier, which enables neurons to detect blood-borne nutrients such as glucose
- sends signals to other parts of the brain to make us eat or not eat
Lateral hypothalamus
- considered one of the main hunger centres in the hypothalamus
- in rats: destructing this area leads to reduced feeding, stimulation promotes feeding
Ventromedial hypothalamus
- plays complementary role in promoting satiety (full feeling)
- destruction of this area leads to overfeeding, and weight gain, while stimulation has the opposite effect
- inhibits the parasympathetic NS, so when destroyed, rest and digest activities become more pronounced
Hormones and neurochemical roles in hunger
- either stimulat or suppress appetite
- orexin, ghrelin, melanin, and endocannabinoids all stimulate feeding
- neuropeptide Y (NPY) is released in the hypothalamus when an animal is hungry
- Ghrelin is released from digestive system; levels rise when we are hungry and fall after we eat… sends signals of hunger to brain
- endocannabinoids increase appetite
- blocking the associated receptors leads to decrease in eating and to weight loss
- insulin, leptin, peptide YY, and cholecystokinin suppress appetite
- insulin is secreted in response to higher blood glucose levels
Food preference
- shaped by evolutionary forces
- crave basic nutrients that our bodies require but were also scarce during ancestral times: sugar, salt, and fat
- preference shaped by culture
- exposure does not immediately lead to preference
- the more often people eat certain foods the more they like them
When we eat and how much
- signals outside of body have strong impact on the timing and size of our meals
- rely on our eyes rather than our stomach to tell us when we are full
Motive to be thin
- in evolutionary past it was important to store as much fat as we could in case it became scare
- no longer need to consume large qualities to be healthy
- thinness has become a cultural obsession
- dieting associated with mood and cognitive disturbances and a significant risk factor for eating disorders
Anorexia nervous
- people who cannot maintain 85% of their ideal body weight for their height, have an intense fear of eating, and have distorted body image
- dont recognize that they are unusually thin or that they have an eating disorder
Bulimia nervosa
- prone to binge eating and feeling lack of control during eating session
- regularly engages in self-inducing vomiting, use of laxative, or diuretics, strict dieting or fasting in order to prevent weight gain
Causes of anorexia
-risks for this disorder include reactivity to stress, genetics, and personality
-women more likely than men
-women with eating disorders show higher physiological reactivity to stress
-56% of influence for eating disorders due to genetics, 38% to environment
More likely to develop anorexia if people demonstrate prowess to anxiety, depression and low self esteem
-more conscientious, introverted and less open to new and novel situations
