WEEK 9 - types of memory Flashcards
types of memory
main split
procedural and declarative
types of memory
Procedural
aka implicit
e.g. riding a bike
NON-ASSOCIATIVE
- habituation: learning to ignore a stimulus
- sensitisation: overreacting to a stimulus
ASSOCIATIVE
- classical
- operant conditoning
types of memory
declarative
aka explicit - NMDAR
EPISODIC AND SEMANTIC
–> SHORT TERM MEMORY
consolidation (BDNF, CREB, protein synthesis)
TO LONG TERM MEMORY (hippocampus
long term memory requires
protein synthesis and the formation of new synapses
does STM require protein synthesis
no
non associative learning
habituation: reduction in response to a stimulus that is delivered repeatedly
sensitisation: enhancement of a response produced by the presentation of a strong stimulus
- can be short term or long term
non associative learning
sea slug
What they did:
First touch the siphon it retracts
Keep touching realises its harmless and no longer retracts
If touch and give electric shock
Next time touches will have a jumping reaction
associative learning:
classical conditioning
Pavlov’s dog
conditioned stimulus: bell
no response
unconditioned stimulus: food
unconditioned response: salivation when seeing food
conditioned response: salivation when hearing bell
Dog forms association between bell and meat
Ringing bell dog salivates as is expecting meat
ALSO aphlysia and gill withdrawal reflex with electric shock
classical conditioning: mechanisms
aphlysia and gill withdrawal
touch depolarised sensory neuron
electric shock to tail depolarises motorneuron
serotonin is released as a result of train of shocks to body wall
- serotonin binds receptor activating DAG and cAMP (PKA, PKC, MAPK)
combination of Glu and depolarisation activated NMDAR
increased:
- synaptic growth
- Ca2+, PKA, neurotransmitter release
- AMPAR
Double input from touch (serotonin) and and shock (depolarisation) (bell and meat)
- Two events for calcium release
classical conditioning: mechanisms
four consequences of the actions of neurotransmitters
- activation of ion channels:
activation potential, lasts milliseconds - activation of G-protein coupled receptor and second messenger, lasts minutes
- persistent transmitter activation of G-protein coupled receptor: Kinase translocates to nucleus, gene expression and persistent synaptic action
- transmitter activation of local protein synthesis stabilises synapse
learning and memory requires the…
hippocampus
memories are formed in the…
hippocampus
memories are stored in the…
cortex
the hippocampus has cells dedicated to form a…
map of space called place cells and grid cells
episodic memories are formed from…
associations between events and place
as neurons in the map of space are activated
this is how we remember our lives
Long term potentiation in the hippocampus
learning and memory result from:
learning and memory result from:
- changes in the strength of the synaptic connections between precisely interconnected cells
- protein synthesis driving the formation of new synapses
memory stored as..
strengths of synaptic connections in a circuit
Firing not always equal
Synapses of different strength
(question: can the intensity of synapses change or does it mean the frequency of firing, or just different synapses have different intensity)
Hebbian learning:
learning occurs by..
changes in the strength of synapses
Hebbian learning:
Hebb’s rule
synapses between two neurons are strengthened when the neurons are activated at the same time
Hebbian learning:
Hebb’s rule in action
synapses that obey Hebb’s rule are Hebbian
they mediate associative learning since they act as coincidence detectors that associate firing of the pre-synaptic and post-synaptic cell
‘neurons that fire together, wire together’
Hebbian learning:
mechanisms increasing synaptic strengthening
long term potentiation (LTP)
Hebbian learning:
mechanisms decreasing synaptic strengthening
long term depression (LTD)
long term potentiation (LTP)
increase in intracellular calcium levels through NMDAR activation
CaMKII is activated by calcium and phosphorylates AMPAR enhancing their response to glutamate
mGluR only at first tetanic stimulation
long term potentiation (LTP)
activation of silent synapses:
acquire AMPAR and become responsive to low frequency input
