L18 Memory Flashcards
(14 cards)
What are the two types of memory?
- Procedural
- Declarative
What is declarative (explicit) memory?
Memory that can be consciously recalled (e.g. recalling riding a shiny new bike on the Christmas day when you were 5)
Recall facts and events
What is procedural (implicit) memory?
Memory that involves remembering how to perform certain actions and skills.
It’s essentially the memory of “how to do” things, rather than “what” things are. Examples including: riding a bike, typing on a keyboard
What are the three different types of memory duration?
- Immediate memory - Few seconds
- Short - term memory - Seconds or minutes.
- Long - term memory - days, months, years.
What does electrical stimulation of the temporal lobe cause?
It induces hallucinations and recollection of the past experiences
Hippocampus and amygdala are in the medial temporal lobe
What is expected to happen if someone undergone temporal lobectomy?
Lobectomy - removal
Extreme anterograde amnesia (inability to form new memories)
Name the important structures of the brain for memory.
- Pre-frontal complex - working
- The hippocampus - essential for converting short to long term memory.
- Amygdala - Fear response, multiple sensory inputs.
- Cerebellum - Procedural, sensorimotor (sports related)
Give me 4 features of the hippocampus?
- Three layered cortex
- Receives inputs from entorhinal cortex and beyond
- Outputs to many regions
- Enlarged in people whose work requires good spatial memory.
What are the mechanisms of memory?
- Long-term storage seems to be distribute
- The Hebbian synapse concept
What is the Hebbian synapse concept?
A theory suggesting if neurons fire together, the connection between those neurons becomes stronger
So its like active recall. The more I remember (use a specific neuron) a fact then the more it’ll stay in my head (neuron becomes stronger)
What is long term potentiation (LTP)?
LTP is how your brain reinforces the connections between neurons that are used frequently, making it easier for those neurons to communicate in the future.
This reinforcement is what allows you to learn and remember.
LTP in hippocampal slices
What is sensitisation?
Refers to an increased responsiveness to a stimulus after repeated exposure to it
What are the features of LTP,LTD and Aplysia?
Long term potentiation, long term depression
- Require receptor activation
- Altered synaptic responsivity
- Mediated by second messengers (Ca2+/cAMP)
- Require protein phosphorylation in early stages
- Require protein synthesis for late stages.
- Involve biochemical and structural pre and post synaptic changes
How does LTP occur?
1) Glutamate released into synaptic cleft
2) Glutamate binds to AMPA and NMDA receptor
3) NMDA receptor allows calcium ions to flow through which activates kinases which phosphorylates the AMPA receptor
4) AMPA causes depolairsation of the membrane on the postsynaptic membrane
