learning & memory Flashcards
(44 cards)
What was the hypothesis of the mechanism of memroy?
measurable changes in synaptic transmission occur as a task is repeated
synaptic facilitation
increased efficacy of synaptic transmission will enhance memory formation
sensitization is a form of synpatic facilitation
facilitation of a synaptic pathway
-primitive form of learning and memory
synaptic inhibtion
suppression of memory formation
habituation is a form of synaptic inhibition
primitive form of memory suppression “learning to ignore”
An aplysia is an invertebrate whcih exhbits primitive forms of memory. How does he exhibit habituation?
decreasesd behavoprial response with repeated stimulation– when poking its tail it willeventually stop withdrawling
An aplysia is an invertebrate whcih exhbits primitive forms of memory. How does he exhibit sensitization?
increased response persisting for days to weeks if a facilitator path activated– if the slug is tazed
Habituation in aplysia may be due to what?
decrease activity of VG Ca2+ channel (adaption) and reduced transmitter release
how does sensitization in aplysia work?
- Facilitator releases serotonin onto sensory neuron terminal
- Adenylyl cyclase activation increases cAMP
- cAMP activation of PKA inhibits S-K+ channels (presumed phosphorylation)
- Sensory neuron terminal depolarized and sensitized
- Transmitter release increased
Key structures of memory
Hypothalamus Hippocampus Amygdaloid body Cingulate gyrus Mamillary body Anterior nucleus Paraolfactory area
Key tracts of the human memory
Fornix- (body and column)
Mamillothalamic Tract
Stria terminalis
how does short term memory occur?
repeated activation of a memory trace circuit could facilitate synpatic transmission for a brief period (reverberating circuit)
intermediate long-term memory occurs for minutes, hours, dyas resulting form what?
a temporary chemical or physical change that persists
long-term memory persists for years; what does it involve?
involves protein synthesis and sturctural synaptic changes
Working memory definition
prefrontal area encodes many bits of information simultaneously and recalls information instantly as needed for subsequent thoughts
consolidation
conversion from short-term to long-term memory
What is the cAMP hypothesis of consolidation?
repeated sensitization increasing cAMP eventually activates CREB and triggers new protein synthesis
declarative (semantic) memory
recal of facts and details
limbic circuits
What are the 2 parallel memory circuits of the limbic system?
anteriror nucleus circuit and the dorsal medial circuit
What is the circuit for the declarative memory?
hippocampus–> mamillary body–> anteriror nucleus to cingulate gyrus
What is the circuit for emotional memory?
amygdala–> dorsal medial nucleus and septal area–> prefrontal/limbic associaton areas and reward center
Where does emotional memory really begin at?
paraolfactory but it has direct input to the amygdala
matches prior experience with current circumstances to evoke an appropriate behavioral repsonse
amygdala
What input is critical for decision-making?
olfactory
