E3 limbic system

Question 1

3 main limbic circuits

Answer 1

memory with hippocampus
emotion with amygdala
reward with nucleus accumbens and ventral tegmental area

Question 2

layers of hippocamups proper

Answer 2

3 is polymorphic layer (0utput)
2 is pyramidal layer
1 is molecular layer (deepest)

Question 3

layers of dentate gyrus

Answer 3

3 is polymorphic (output)
2 is granular
1 is molecular (most superficial)

Question 4

hippocamups internal loop

Answer 4

long term storage
cotical association areato to entorhinal
to dentate gyrus granule cells via perforant path
to CA3 pyramidal neuroons via mossy fiber system
to CA1 pyramidal neruans via schaffers collaterals
to subiculum and back to entorhinal and to coritcal association areas for storage

Question 5

hippocampus external lop

Answer 5

CA3 gets input same way and again sends to CA1 and to subiculum but then from CA1 and subiculum through alveus and fornix to septum and mammilary body
then to anterior nucleus of thalamsus via mtt the n to cinulate gyrcus then to entorhinal cortex and out to cortical association for storage

Question 6

long term potentiation

Answer 6

some handwaving about the strength of synaptic connections
happens in granule cells and pyramidal cells of CA1, CA3
basically after tetanic stimulation the same stimulus produced a greater response

Question 7

hippocampus and alzheimers

Answer 7

CA1 hit first and worst

extracellular plaques and intracellular tangels

Question 8

hippocampus and ischemia

Answer 8

CA1 usually gets deprived of oxygen and loses cells

Question 9

hippocampus and epileptic seizures

Answer 9

most electrically excitable part of brain

too much glutamatergic transmission

Question 10

kluver bucy syndrom

Answer 10

bilateral lesion of temporal lobes
visual agnosia
oral tendencies
hypermetamorphosis
emotion dulled and loss of fear
hypersexuality
from herpes eimplex encephalitis
anterograde amneisia

Question 11

korsakoffs syndrom

Answer 11

thiamine deficieincy
anterograde amnesia
retrograde amnesia
confabulation

Question 12

3 amygdala nuclei

Answer 12

latearl LA for sensory input
basal B for contextual input from hippocampus
central CE output

Question 13

2 output pathways of amygdala

Answer 13

stria terminalis to hypothalmus

vantral amygdalofugal pathway VAFP to hypothalamus and MD thalamus

Question 14

short route amygdala

Answer 14

sensory thalamus directly to amygdala

low info but fast

Question 15

long route amygdala

Answer 15

sensory thalamus to sensory cortex to amygdala

slow but more context

Question 16

ventral tegmental area

Answer 16

dopaminergic
mesolimbic pathway
mesocortical pathway

Question 17

mesolimbic pathway

Answer 17

VTA to nucleus accumbens

Question 18

mesocortical pathway

Answer 18

VTA to prefrontal cortex

Question 19

Nucleus accumbens

Answer 19

reward pleasure addiction
GABA ergic
inputs from PFC, amygdala, hippocampus, VTA
outputs to netral pallidium to mediodorsal nucleus of thalamus to pfc
GABA so inhibits VP so disinhibits MD which then activates PFC

Question 20

cocaine exampel

Answer 20

dopamine reuptake inhibition
tolerance
dependence and withdrawal
craving
implicit emotional memories and cravings basically forever

Question 21

HPA axis

Answer 21

hypothalamic pituitary adrenal axis
paraventricular nuclues
anterior pituitary gland
adrenal cortex
stress activates PVN to release corticotrophin releasing factor/hormone to tell anterior pituitary to release adrenocoritcotropin hormone which tells adrenal cortex to release glucocorticoids like cortisol
this results in anti inflammatory and immunosuppressive actions

Question 22

SAM axis

Answer 22

sympathetic adrenal medullary axis

fight or flight

Question 23

autoregulation of HPA axis

Answer 23

corisol has negative feedback loop on hippocampus, PVN and anterior pituitary

Question 24

dysregulation of HPA axis

Answer 24

chronic stress

less cortisol receptors so negative feedback stops working

Question 25

dysregulation of SAM axis

Answer 25

chronic hurts immune function