Memory Flashcards
what are the definitions of learning, memory, recall and ‘the engram’?
learning = acquisition of info/skills
memory = storage of learned info
recall = reacquisition of stored info
the engram = physical embodiment of a memory
what are the 2 independent memory systems?
- procedural - implicit
2. declarative - explicit
what is procedural memory?
- skills and associations that are largely unavailable to the conscious mind
- e.g. acquired skills which after you practice you can naturally do e.g. riding a bike
what is declarative memory?
- available to conscious mind
- can be encoded in symbols and language
- e.g. speaking/communicating knowledge
what is explicit memory?
- memory that can be consciously recalled
- e.g. recalling riding a new bike
what is implicit memory?
- memory that cannot be consciously recalled
- e.g. learning to ride a bike
what are the 3 types of implicit memory?
- Procedural memory
- classical conditioning e.g. Pavlov’s dogs
- Priming - when one stimulus influences the response to subsequent stimuli
what are the 3 types of memory duration?
- immediate memory = few seconds
- short-term memory = seconds/minutes
- working memory - long-term memory = days/months/years
how is the temporal lobe involved in memory?
- electrical stimulation of the temporal lobe causes hallucinations and recollection of past events
- important in generating long-term memory
what are epileptic seizures?
when neurons in local, specific areas of the brain fire APs uncontrollably, causing complex sensations and memories
what happens when a patient’s temporal lobe is removed? (lobectomy)
- intelligence, personality and long-term memory in tact
- epileptic seizures stopped
- extreme anterograde amnesia - couldn’t acquire new memories
what are the important brain structures involved in memory?
- Prefrontal cortex: working memory
- Hippocampus: declarative memory
- converts short to long term memory - amygdala: implicit memory
- multiple, processed sensory inputs i.e. emotional memory and learnt fear - cerebellum: procedural memory
- sensorimotor
how is the hippocampus involved in memory?
- 3 layered cortex with inputs from the entorhinal cortex
- outputs to many regions
- enlarged in people with good spatial memory
- hippocampal lesions cause memory loss
what are the mechanisms of memory?
long-term storage is distributed across brain regions
reverberating circuits: memory part of a specific population of neurons in the brain
the Hebbian synapse concept: gain of synapses increases/decreases during memory formation
- synaptic plasticity
what is the Hebbian synapse concept?
- synaptic strength changes cause an increase in amplitude of EPSP
- facilitation/depression: short-term changes in synaptic strength due to Ca2+ availability or vesicle depletion
- long-term facilitation/depression is sustained