lecture 10: limbic system Flashcards
limbic lobe is a ______ structure that forms a ______ boundary when including the __________
cortical
circular
olfactory bulb & tract
limbic lobe does not share a boundary with which lobe?
occipital
what are 3 main structures of the limbic lobe?
- cingulate gyrus: ant & post
- parahippocampal gyrus: entorhinal cortex
- uncus: piriform cortex – primary olfactory cortex
the piriform cortex used to be called the __________ because it was thought that it played a role with the olfactory area but now it was found it doesn’t anymore
rhinencephalon
what structure is directly related to the limbic system but is not classified as part of the limbic system?
cerebellum
true or false. we still use the Papez circuit to define the functions of the limbic system
false –> more things added to it. now called the spiral model
what is emotion?
integrated physiological changes, behavioral reactions and feelings
what are the two theories of emotion classification?
1) distinct _____ basic emotions
2) _______ with arousal level w/ neg. to post. valence –> aka you never have ________ emotion
1) 6
2) spectrum ; neutral
the hypothalamus forms the ________ wall of the _____ ventricle
it is located _______ to optic chiasm
anterolateral ; 3rd
superior
life and death functions of the hypothalamus:
- homeostasis/initiation of drives (individual survival)
- reproduction (species survival)
- bridging endocrine and nervous systems
function of the 6 hypothalamic nuclei:
1. lateral nucleus:
2. ventromedial nucleus
3. posterior nucleus
4. anterior nucleus
5. paraventricular nucleus
6. supraoptic nucleus
- hunger center
- satiety center
- heating center
- cooling center
- produces oxytocin
- produces vasopressin ADH
neurohypophysis:
- location:
- developed from:
- stores & releases which two hormones?
- functions of these two collectively:
- posterior pituitary
- diencephalon
- oxytocin (myometrium contraction & breast smooth muscle) AND ADH (water absorption & increase BP)
- mating, bonding, brain development
adenohypophysis:
- location:
- developed from:
- what carries hormones to adenohypophysis?
- which hormones are released to the adenohypophysis?
- anterior pituitary
- posterior oral cavity (Rathke pouch)
- hypophysial portal vein
- thyrotropin-releasing, growth hormone-releasing, growth hormone release-inhibiting, corticotropin-releasing, gonadotropin-releasing, prolactin-releasing
temperature regulation reflex (intrinsic):
- specialized _______ neurons in hypothalamus
- normal blood temp. setpoint:
- when blood flows through the neurons & temp is detected, if the temp is lower than the setpoint, what is activated?
- when blood flows through the neurons & temp is detected, if the temp is higher than the setpoint, what is activated?
- rostral (ant.) hypothalamus function:
- caudal (post) hypothalamus function:
- temp-sensing
- 37 deg C
- posterior nucleus (increase heat)
- anterior nucleus (sweat to decrease heat)
- heat dissipation (cool)
- heat conservation/production (heat)
what is happening when our body produces a fever?
cytokines/bacterial endotoxin increases the body temp past the setpoint –> increased temp will kill viruses
what is happening to women’s bodies in postmenopausal syndrome?
irregular body temp setpoint –> setpoint changes due to loss of hormones
water balance reflex (neurohumoral):
- specialized ________ neurons in hypothalamus
- if plasma osmolarity is too high _____
- if plasma osmolarity is too low _____
- osmolarity-sensing
- increase ADH –> keep more water in
- decrease ADH –> pee too much
_______ blocks ADH release –> urinates too much
alcoholism
not enough ADH is released into the blood in a patient with ________
diabetes insipidus –> pee all the time
Baroreceptor reflex (extrinsic):
- maintains:
- afferent signal:
- efferent signal to counteract:
- effect:
- blood pressure
- baroreceptors in carotid sinus (CN IX) and aortic arch (CN X) (increase BP)
- CN X
- decrease HR/BP
what structure can over-ride the baroreceptor reflex? typically needed in fight or flight situations when we need an increase in HR
hypothalamus
functions of projections of the hypothalamus:
- medial frontal lobe:
- cerebellum:
- fornix –> amygdala:
–> hippocampus:
- thalamus:
- spinal cord/brainstem:
- regulating drives/emotion
- emotion/motor skill memory –> integration of somatic and visceral motors
- 1: emotion 2: declarative memory
- coordination
- homeostasis and motor execution
location of amygdala:
- ______ to inferior horn of lateral ventricle
- ______ to optical tract
- _______ to hippocampus
- medial
- lateral
- anteromedial
3 clusters of nuclei in amygdala:
- medial
- central
- basolateral
- olfactory tract
- hypothalamus and brainstem nuclei
- different cortex region and sensory pathway
