Karius: learning and memory Flashcards
what are the different types of memory?
- working
- declarative
- Procedural
- short term
- long term
Describe Procedural memory
- aka implicit, non-declarative, reflexive
- skills and habits that have been used so much they are automatic
- like riding a bike
What are the anatomic substrates for procedural memory
- Cerebellum - motor skills
- Nucleus accumbens - non motor
Describe Declarative memory
- aka explicit memory
- the conscious recognition/recollection of learned fact and experiences
what are the 2 forms of declarative memory
- Episodic: memory of events
- Semantic: memory of words, language, and rules
Describe working memory
- you’ve learned it, now you are retrieving it for use
- will look very much like short term memory
The production of memory and learning requires the induction of what?
neuronal and synaptic plasticity
what are the changes in synaptic function that occur with plasticity
- Post-tetanic potentiation
- Pre-Synaptic facilitation
- Long-term potentiation (LTP)
What are the changes in the structure of the neurons that occurs with plasticity?
- Gain/loss of synapses
- Structural changes in dendrites
- Structural changes in the soma of the neuron
Describe Post-Tetanic Stimulation
- brief, high frequency discharge of presynaptic neuron
- Produces increased neurotransmitter release
- lasts about 60 seconds
- The high level of stimulations allowed more Ca to enter to the terminal than could be “dealt” with
Describe Pre-synaptic facilitation
- Start with a normal chemical synapse
- now add another neuron that synapses on the presynaptic terminal of the first neuron
- when activated this terminal releases serotonin (5HT)
- leads to activation of adenylyl cyclase and increased cAMP
- K+ channels in the neuron become phosphorylated and opening is delayed thus repolarization is delayed
- this leads to greater neurotransmitter release
Describe Long-term potentiation
- A series of changes in the pre and post synaptic neurons of a synapse which leads to increased response to the released neurotransmitter
- by definition, this increase in response must last for hours after the stimulation
- usually follows strong stimulation
mechanism of increased response in long term potentiation in POST synaptic neuron
- increased intracellular Ca: via influx through NMDA receptors and release from intracellular stores
- increased binding of Ca to neuronal calmodulin: increased adenylyl cyclase activity and increased CAM-kinaseII
- increase cAMP
- protein kinase A activation
- increased phosphorylation of AMPA receptors
- CAM-kinase II autophosphorylates: leads to prolonged activation. it also phosphorylates AMPA and NMDA
- increases the amount of current ions flowing into the cell
- leads to an increased epsp amplitude in response to same amount of neurotransmitter release from pre synaptic neuron
how does long term potentiation affect PRE synaptic neuron
- increased Ca in post synaptic leads to activation of NOS
- produces NO which diffuses out and into pre synaptic
- increase in cGMP
- increased neurotransmitter release with future action potentials
Long term potentiation is associated with gene transcription related to increase in what?
CREB: cAMP response element binding protein
