limbic system and memory

memory structures

post cingulate gyrus, medial thalamic nucleus, mammillary body, hippocampus, parahippocampal gyrus, nucleus basalis, nucleus accumbens

emotion structures

ant cingulate gyrus, septal area, orbitofrontal cortex, amygdala, ant thalamic nucleus

hippocampus

important for processing to create long term memories, does not store memories, cholinergic activity important
CA1: long term potentiation, affected by global ischemia

bilat hippocampus damage

difficulty creating new memories (anterograde amnesia)

amygdala

threat detection, helps determine response
under uncus in med temporal lobe
memories inform amygdala

Kluver-Bucy syndrome

bilat temporal lobe lesions including amygdala
visual agnosia, hyperorality, hypermetamorphosis, placidity, hyperphagia, hypersexuality

emotional memory

high emotions can have chronic effect on memory

declarative memory

facts, processing occurs in parahippocampal cortex and hippocampus

procedural memory

skills learned, practice is required, once acquired attention not required
cognitive, associative, autonomous phases
prefrontal and motor cortex, basal ganglia, cerebellum

cellular mechanisms sec-min

ongoing electrical activity, changes in ions, changes in 2nd messenger systems

cellular mechanisms min-hours

protein phosphorylation, expression of immediate early genes to help maintain info and begin to push to long term maintenance

cellular mechanisms hours-years

changes in gene transcription and translation resulting in structural changes of proteins and neurons, embeds memory into system

anatomical structure storage less than 1 sec

brainstem-diencephalic systems, frontoparietal association networks, unimodal and heteromodal cortices

anatomical structure storage working memory

frontal association cortex, specific unimodal and heteromodal cortices

anatomical structure storage consolidation

hippocampus, med diencephalic structures, specific unimodal and heteromodal cortices

anatomical structure storage years

specific unimodal and heteromodal cortices

LTP: cooperativity

more than one fiber must be activated

LTP: associativity

contributing fibers must be activated together

LTP: specificity

potentiation must be specific to only activated pathway

Alzheimer’s

severe loss of cognitive function without impairment of consciousness
loss pyramidal cells in brain, amyloid plaques, neurofibrillary tangles, loss of cholinergic neurons (important for memory function)