Learning memory Flashcards
What are implicit memory and what brain regions are important?
Unconscious memories.
Skills & habits: cortex, basal ganglia and cerebellum.
Emotional association: amygdala. Conditioned reflexes: cerebellum
What are explicit memories and what brain regions are important?
conscious memories.
Episodic: remembering events
semantic: knowing facts.
Hippocampus, nearby cortex and parts of the thalamus
What are some differences b/t short-term memory (working memory) and long-term memory?
Short term: small capacity, fades quickly unless rehearsed.
Long term: Infinite capacity, last indefinitely, could be forgotten but later remembered with certain cues.
What part of the brain is important for working memory?
Prefrontal cortex
What were HM’s impairments; what could he still do?
HM had parts of the temporal lobe w/ hippocampus removed. It had little effect on his perception, intelligence and personality but he had anterograde amnesia (cannot form new memories).
What other brain regions are important various types of memory?
Cerebellum Striatum Prefrontal cortex Amygdala Inferotemporal cortex
What does cerebellum do for memory?
stores memories of sensorimotor skills & conditioned reflexes
What does the striatum do for memory?
habit formation
What does the prefrontal cortex do for memory?
working memory & temporal order of events
What does the amygdala do for memory?
emotional association. Unknown if stores mems or strengthens emotionally significant memories somewhere else
What does the inferotemporal cortex do for memory?
stores memories of visual input
What are concept neurons?
The concept that certain cells are meant to respond to particular individuals, or places related individuals
What is standard consolidation theory?
hippocampus stores memories temporarily while consolidating the memory. Consistent w/ the temp retrograde amnesia
What is another explanation for what the hippocampus does with memory?
new experiences are rapidly and sparsely encoded in hippocampus and related structures. Memories strengthen over time w/ similar experiences/recall
What is a Hebbian synapse?
A synapse that increases in effectiveness b/c of simultaneous activity in pre & postsynaptic neurons. “cells that fire together, wire together.”
What is LTP?
Long-term Potentiation: a burst of stimulation from axons. 100 excitations per second on the dendrites result in potentiated synapses for minutes/days/weeks
What receptors are necessary?
Glutamate receptors: AMPA & NMDA
Understand cooperativity in LTP
nearly simultaneous stimulation by two or more axons results in LPT
Understand specificity in LTP
only active synapses become strengthened
Understand associativity in LTP
pairing a weak input w/ a strong input enhances later responses to the weak input
What are some presynaptic changes that occur in LTP?
Retrograde transmitter from dendrite to axon terminal usually nitric oxide. Decreased threshold for producing Aps. Increased release of neurotransmitter. Expansion of axon. Release of NT from more sites along axon
What gas neurotransmitter is involved in these changes?
Nitric Oxide NO
What is evidence that there is a functional connection between LTP and actual learning?
Mimics normal activity, LTP effects are greatest in brain areas involved in learning & memory. Learning produces LTP like changes.
What are the 3 parts of LTP?
Induction
Maintenance
Expression
