Flashcards in 3: Motivation of Eating Deck (30)
What is instinct theory?
The idea that all behaviour is driven by instincts which aid survival
How does Maslow's Higherarchy of needs link to motivation to eat?
We can't move up the pyramid until our physiological needs are met such as food and sleep
What is arousal theory?
Motivation aims to keep us at optimal levels of arousal. Arousal increases performance until optimal levels are reached, but after that it may hinder it
What is the function of the cortical arousal system?
To arouse the brain
What is the function of the ascending reticular activating system?
To regulate sleep and wake transactions
What are the 3 phases of digestion?
What is the cephalic/reflex phase of digestion?
Body prepares itself for food through salvation. Initiated by the sight or smell of food
What is the gastric/absorbative phase of digestion?
Triggered by food in the stomach
Ph levels in the stomach are lowered, leading to an increase in HCL
What is the intestinal phase of digestion?
Food is broken down in the stomach and passed into the intestines
How is energy stored in the body?
What is drive reduction theory?
The physiological need (Hunger) creates arousal tension so we are motivated to satisfy it
It's aim is to maintain homeostasis
What is the glucostatic hypothesis? (Part of reduction theory)
Low blood glucose increases appetite
After a meal, insulin increases to make use of glucose
What is the role of insulin in appetite?
Reduces appetite when it enters the brain. Mice with disrupted receptors have a higher rate of food intake and obesity
What is ghrein?
A hormone made by the stomach to stimulate appetite
What is PYY?
A hormone produced in the lower gastrointestinal tract that supresses appetite
What is the lipostatic hypothesis? (Part of drive reduction theory)
Levels of fat influence food consumption to maintain a stable body weight
How is the hypothalamus involved in appetite?
Regulates metabolic processes
Leisons lead to deminished appetite
What is set point theory?
When we fall below our body's natural normal weight, we're triggered to eat more. When we're too heavy, our metabolic rate increases
What is positive insentive theory?
We're motivated to eat by anticipated pleasure
According to positive inscentive theory, what affects consumption?
Size of bowl
How does classical conditioning demonstrate the importance of external factors in eating?
Rats conditioned to assocate buzzer with food. Only ate when the buzzer sounded, even if they were already well-fed.
What is sensory-specific satiety?
If we eat a specific food until we are sated, our perceived pleasure for that food goes down
What is the mesolimbic dopamine pathway? (Reward circuit)
Ventral tagmental to the nucleus accumbens, hippocampus and amygdala.
Feeding triggers dopamine and blocking dopamine leads to food being devalued
What are the main features of anorexia nervosa?
Persistant restriction of energy intake to signifanctly lower body weight
Fear of gaining weight
Lack of recognition around their own body weight
What are the main features of bulimia?
Reccurent episodes of binge eating
Lack of control over eating
Compensatory behaviour to avoid weight gain
What is th main feature of binge eating disorder?
Binge eating more rapidly than usual and feeling discusted with yourself after
What are the biological explanations of anorexia?
Hypothalamus dysfunction theory
What is the hypothalamus dysfunction theory of anorexia?
Lack of a weight thermostat and a struggle to support internal body tempreture
BMI is correlated to grey matter in the hypothalamus
What is the biochemical imbalance theory of anorexia?
Hypersensativity to dopamine means food triggers anxiety instead of pleasure