EATING BEHAVIOUR-neural mechanism in control eating b Flashcards
what is metabolism?
regulated by physiological mechanism & aims to keep body in homoestastics
what is homeostatics?
automatic functioning within body e.g temp,heart rate,hunger & satiety
what is satiety?
keeps us full
what is the dual control theory?
idea of hunger is regulated by 2 parts of hypothalamus
what is dual control theory based on?
hypothalamus
what is process with hypothalamus?
eat meal and releases certain chemicals- brains see levels of g increase and stop eating. glucose burnt then low so danger of losing energy. low= start eating. if we ignore other parts of brain stimulate and recog levels of other chemicals
what is the chemical it releases?
glucose
what is it also known as (process)?
negative feedback loop
process of what happens when we’re hungry?
lateral hypothalamus= activated & ghrelin= weak w o no glucose. lepton goes into free fat cells in blood. 2 types ceplin goes in and when poefed = full when out get thin.
not just 1 mechanism we go through then how many?
3 but we gonna do 2.
what 2 theories/mechanism do we go?
dual centre theory
set point theory
what is dual centre theory also linked to?
boundary model theory in dieting
what is set point theory?
our body weight is regulated by a biologically determined standard
who suggested our body weight is regulated by a biologically determined standard ?
keeley
point 2 for set point theory?
our homoestatic mechanism alters our metabolism and appetite if we eat too much/little which returns us to our normal weight
point 3 for set point theory?
if we have boundary of weight how people get obese/anorexic - we screw with our own biology
what did passer et al say?
but if we are persistent over or under eaters then the mechanisms struggle results = new set weight
what is dual centre also?
automatic function
what is the two important components for the dual centre?
lateral & vetrimenal hypothalamus
when does hypothalamus mean?
main area of the brain implicate in appetite regulation (deepest part of head to damage)
what is 2 areas of the hypothalamus?
lateral & ventromedial hypothalamus
what is lateral hypothalamus?
switches hunger on. damage to this area= food intake automatically reduced
what is lateral hypothalamus also known as?
hunger centre
what is vmh?
switches eating off, tells us we are full (satiety) and appetite reduces - damage 2 area = increased appetite
vmh also known as?
satiety centre
what does the set point theory suggest? (in relation to dual centre)
suggests that food consumption & weight control are a result of balance between these 2 areas & other metabolic processes
diagram intro?
as glucose levels decrease hunger levels increase increase in g lev means satiation released
what happens in lh with glucose levels?
low in g level activates area and feel hungry. individ look for food and eats
what happens in vmh with glucose levels?
increase in g levels activates this area and feel satiation -inhibits further eating
what is the function of the dual centre area?
homoestatis- dont need to think bout this stuff
what about type 2 diabetes and this diag?
we develop later in life.increase in type 2 because glucose lev high
A02 for pathway cases?
berthound & morrison
wood
leibowtz
what did bethard & morrison?
not just g that affects b/hunger
in depth bethard & morrison?
look at circuits within hypothalamus - found many of the pathways involve the para ventricular nucleus (receptors) for transmitters which stimulate or reduce appetite are found in this cluster of neurons.
what is influenced by signals from pvn?
metabolic and digestive processes
what did woods say?
neuropeptide is one signal. increase levels of npy in pvn = food intake & weight increase when leptin levels low ,npy lev increase
what did leibowtz?
rats injected with npy consume large amounts of food even when full. preference of food shown in carbs
what is galanin?
another peptide found in pvn (leibowtz) when thi is injected into rats, again food intake increased food preference shown fats
what do cravings work on?
individ not enough of something bod & stimulas vmh to find food (lh)
