lecture 11 End Section ----------------------------------------------------- Flashcards
memory and learning
where was long term potentiation first discovered?
on the hippocampus
in terms of LTP, what is the effect of repetitive stimulus of a particular synapse?
eventually leads to an increase in strength of the synaptic connection
new synaptic connections are are formed from LTP, T/F?
True
with regards to LTP, what is input specific?
Only the activated set of synapses onto a particular cell will be potentiated, whereas unactivated synapses to that same neuron remain unpotentiated
what does the induction of LTP require?
coincident activity/cooperativity of the presynaptic terminal plus significant depolarization of the postsynaptic membrane
what neurotransmitter affects LTP and LTD?
glutamate which can activate NMDA and AMPA affecting entry of calcium affecting the LTD and LTP
Induction Mechanisms of LTP and LTD…The Calcium Hypothesis
Ca levels for No Stimulus
Ca = 50 - 100 nM
Induction Mechanisms of LTP and LTD…The Calcium Hypothesis
Ca levels for Single Stimulus
Ca = 50 - 100 nM
Induction Mechanisms of LTP and LTD…The Calcium Hypothesis
Ca levels for Low Frequency Stimulation
180 to 450 nM
Induction Mechanisms of LTP and LTD…The Calcium Hypothesis
Ca levels for High Frequency Stimulation
> 600 nM
Induction Mechanisms of LTP and LTD…The Calcium Hypothesis
Ca levels for LTP
> 600 nM
Induction Mechanisms of LTP and LTD…The Calcium Hypothesis
Ca levels for LTD
180 - 450 nM
what is the relationship between synaptic connections and LTD?
Weakening of synaptic connections
what is Broca’s aphasia?
Patient will be unable to say what he/she wants to say, fontal lobe affected
what is wernicke’s aphasia?
Destruction of the visual and auditory association areas results in an inability to understand the written or spoken words, temporal lobe
describe the corpus callosum?
Connects the two hemispheres and transfers information between them
Dominant Hemisphere: understands the spoken word
Non-Dominant Hemisphere: understands written word and can elicit motor response without dominant side knowing why response was performed
Immediate memory
last for seconds to minutes
Short-term memory
lasts for days to weeks
Long-term memory
lasts for years to a lifetime
how does long term memory result?
Results from a structural change in synapse → increase area for vesicular release via synthesis of release site proteins → more neurotransmitters are released
During inactive periods, the area decreases in size
what is the molecular basis for memory?
Transmitter activates G protein → adenylate cyclase is activated → increase in cAMP
cAMP activates a kinase that phosphorylates a component of the K channel blocking its activity
This prolongs the action potential which increases transmitter release
anterograde amnesia?
can’t make new memories; long-term memory is intact
retrograde amnesia?
unable to remember memories from the past
what is neuronal plasticity?
Ability to change neuronal connections on the basis of experience
New synaptic connections can develop
