eating and appetite Flashcards
outline the rat study that investigates learned taste preferences and aversion
- 2 conditions
- one conditions had rats trained to eat flavour A
- flavour A paired with glucose
- flavour B = no flavour, no nutritional value
- rats preferred flavour A
- this is known as conditioned taste preference
- other condition paired flavour A with lithium chloride (induces nausea)
- found that rats avoided flavour A
- this is known as conditioned taste aversion
suggests that taste preferences can be learned
what is the ventral-medial hypothalamus?
- satiety centre
- region of brain that inhibits eating
outline a rat study into lesions in the ventral-medial hypothalamus
(Hetherington & Ranson, 1940)
- found lesions to VMH caused hyperphagia
- hyperphagia = overeating phenomenon & obesity
what does lesions to the VMH lead to?
- VMH syndrome
describe the two stages of VMH syndrome
1/ dynamic phase
- excessive eating
- a lot of weight gain
2/ static phase
- body weight = maintained
- overweight state returns following diet
what is the lateral hypothalamus?
- feeding centre
- opposite of the function of VMH
outline a rat study into lesions in the lateral hypothalamus
(Anand & Brobeck, 1951)
- found lesions caused aphagia
- aphagia = stopping of eating
- lesions cause LH syndrome
descrive LH syndrome
1/ aphagia
2/ adipsia
what is aphagia often accompanied with?
adipsia
stopping of drinking
how can you recover from LH syndrome?
- feeding tube
- milk soaked cookies
- dry food pellets
outline physiological research on the stomach by Cannon & Washburn (1912)
- Washburn swallowed a balloon
- balloon with bit of air went into stomach
- balloon was attached to seismograph
FINDINGS
- contractions caused by empty stomach correlated significantly with feelings of hunger
is stomach necessary to feel hungry?
- no
- found that patients without stomachs still get hungry
- stomach = sufficient but not necessary
