Motivation of Basic Drives Flashcards
Allows the brain a way of setting priorities
Motivation
What are the two types of motivation?
- Strategic (long-term) motivation
- Immediate (innate) motivation
What are the three stages necessary to maintain homeostasis?
- Sense the current state
- Compare to wanted state
- Correct for difference
The most important brain area for homeostatic regulation
The hypothalamus
What percentage of adult Americans are obese?
40%
The “hunger center” of the brain, also involved in arousal
The lateral hypothalamus
Term for “no eating”
Aphagia
The “satiety center” of the brain
Ventromedial hypothalamus
Term for “abnormally increased eating”
Hyperphagia
Satiety hormone, produced by fat-storing cells
Leptin
Can Leptin cross the blood-brain barrier?
Yes!
Hunger hormone, located in the stomach and is secreted before meals
Ghrelin
Part of the hypothalamus that is involved in hunger/ feeding
The Arcuate Nucleus
Neurons located in the arcuate nucleus that increase satiety, stimulated by Leptin
POMC neurons
Neurons in the arcuate nucleus that are stimulated by ghrelin, increase feeding
AGRP neurons
Why doesn’t injecting leptin in obese individuals cause weight loss?
Obese individuals have leptin but the receptors have been desensitized
Thirst associated with a reduction in blood volume/ pressure (bleeding, vomiting, diarrhea)
Hypovolemic thirst
Thirst associated with an increase in extracellular solute concentrate (perspiration, respiration, urination)
Osmotic thirst
Detect blood pressure drops, located in the heart and veins
Baroreceptors
Pathway associated with hypovolemic thirst, baroreceptors send information to the nucleus of the solitary tract in the brainstem
Neural pathway
Pathway associated with hypovolemic thirst, low blood pressure causes kidneys to release Renin
Endocrine pathway
Final part of the endocrine pathway, enters the brain to cause thirst
Angiotensin ll
Cells that detect extracellular fluid pulling water from neurons, located in the hypothalamus. They they send signals to increase thirst
Osmoreceptor neurons
The observation that males and females typically exhibit differences in sexual behavior
Sexual dimorphism
Elicits sexual behavior in females, does not affect sexual behavior in males
Ventromedial hypothalamus
Ellicits sexual behavior in males, does not affect sexual behavior in females
Preoptic area
Phenomenon where male preoptic lesions leave appetitive sexual motivation intact, but leave them unable to copulate
The Consummatory Effect
Phenomenon where male rats still copulate after lesion to the amygdala, but motivation to seek a female is gone
Appetitive Effect
