Module 18 - Learning and memory I Flashcards
Learning
The acquisition of new knowledge or skills
Learning is “adaptive”
Memory
The retention of learned information
Linked to storage and retrieval
The two types of memory
Declarative memory - explicit: facts/events
Non-declarative memory - implicit: habits/procedural skills/associations
Where are memories stored within the brain?
Hippocampus - explicit memory
Cerebellum and basal ganglia (striatum, putamen) - procedural memory
Amygdala - emotional responses
Many regions of the cortex - short/long-term explicit memory
Place cells
Hippocampal neurons associated with navigation - they fire at a high rate whenever the animal is in a specific location in the environment, called the place field
Cognitive map
An internal neural representation of the landscape in which an animal travels
Hippocampus: evidence of its role in spatial memory
London taxi drivers have greater grey matter in the hippocampus than bus drivers (correlated with years of navigation experience)
Short-term memory: how long does it last, how is retention improved, what is its capacity, is it labile or stable, does it require new RNA or protein synthesis?
Lasts for seconds to hours (usually <30s tho)
Repetition promotes retention
Limited capacity (typically 5-9 pieces of info)
“Labile” (sensitive to disruption)
Does not require new RNA or protein synthesis
Working memory
Used as an active memory process, holding memory in the mind, transfers and uses memory between both stores
Long-term memory: how long does it last, what is its capacity, is disruption possible, does it require new RNA or protein synthesis?
Lasts for days to years
Unlimited capacity
Consolidated (insensitive to disruption) but interference may occur
Does require new RNA or protein synthesis
The basic processes behind the formation of memories
Involve changes in existing neural circuits - altered synaptic strength and neuronal excitability included
Intracellular signalling pathways play a key role in effecting these changes
Activity-dependent synaptic plasticity
Neurons that fire together wire together - the more that neuron B excites neuron A some growth changes/metabolic changes occur
Long-term potentiation: what is it, what does it produce?
LTP is the principal model of mechanisms underlying learning and memory stating that a persistent strengthening of synapses following a high-frequency stimulation of a chemical synapse
Produces a long-lasting increase in signal transmission between two neurons and represents one mechanism of synaptic plasticity
Glutamate receptors: the two types and how they open and what influxes they allow
AMPA receptor requires glutamate to open and then allows Na⁺ influx
NMDA receptor requires glutamate + glycine + depolarisation to open and then allows Na+ and Ca²⁺ influx
LTP mechanisms: the process behind LTP formation
AMPA and NMDA receptors involved
Presynaptic changes occur - increased NT vesicles and increased NT release. then, postsynaptic changes - increased dendritic area and spines (increased sensitivity) and increase AMPA receptors
