limbic system Flashcards
what is the limbic system
bridge between sensory, autonomic and voluntary behavior
limbic system is concerned which
feelings, emotions, and drive-related behaviors important to the survival of the species
components of the limbic system
cingulate or parahippocampal gyrus
amygdala
hippocampus
septal nuclei
hypothalamus - mammillary bodies
reticular formation- midbrain
olfactory structures
medial amygdala function
olfactory system
central amygdala
hypothalamus and brainstem, important for expression of emotions (HPA axis)
basolateral amygdala
connections with cortex
inputs to limbic basal ganglia loop
amygdala, hippocampus, limbic cortex
cortex projects to where in LBG loop
ventral striatum
VS projects where in LBG loop
ventral pallidum
VP projects where in LBG loop
dorsomedial thalamus
DM thalamus projects where in LBG loop
back to cortex
function of the LBG loop
actions and movements related to stimuli and expected reward
- significant role in addiction
functional aspects of amygdala
emotional learning
effect of bilateral amygdala removal
loss of emotional content of memories and reduced fear/aggression
stimulation of amygdala
attentive, defensive, aggressive or fleeing
- humans become fearful
amygdala and hippocampus regulates what
CRH neurons in the hypothalamus
stress stimuli to the basolateral amygdala causes what
hypothalamic neurons to release CRH
ACTH causes what
cortisol release from the adrenal gland
ACTH effect on immune system
suppression of immune system
Learning
acquisition of new info
memory
retention of learned info
engram
physical representation of location of a memory
amnesia
serious loss of memory or ability to learn
dementia
loss of cognitive or intellectual function
3 functional elements of declarative memory
acquisition, storage and retrieval
memories that are harder for form but less likely to be forgotten
non-declarative/procedural
outcome of bilateral removal of hippocampus, adjacent temporal lobes
severe anterograde amnesia, but no loss of procedural memory
inputs to hippocampus
cingulum, entorhinal cortex, olfactory bulb
formation of emotional memories relies on
amygdala
