Learning and Memory Lec07 Flashcards
____ memories are available to consciousness: daily episodes, words and meanings, history
Declarative
where are declarative memories stored on the short term
hippocampus
where are declarative memories stored on the long term
cortical sites
where are nondeclarative memories stored on the short term
their storage is diffuse throughout the brain
where is long term sotrage of nondeclatative memory
cerebellum basal ganglia, promotors cortex, other motor behavior sites
The ___ is needed for declarative memory
hippocampus
Patient RB: bilateral brain damage to area CA1 of the hippocampus
how was her memory imapirment compared to HM?
similar to but less severe than HM’s
What is Consolidation
acquisition and storage of declarative memory
what does consolidation involve?
transfer from
hippocampus to cortical structures
Long term memory (ENGRAM) depends on changes in
synaptic transmission efficacy
LTP is ___ specific
input
___ ion channel is critical to LTP
NMDA receptor
what does NMDAR need to open?
- lignad binding
- coagonist glycine
- sufficient depoalrization to kick out Mg
LTP strengthening mechanisms:
- Insertion of _more AMPA post synaptic
receptors_ -
More pre synaptic vesicles = increased
Glu release = longer channel open
time - _Metabotropic Glu (mGlu) receptors
activated_–> kinases. IP3 promotes release of intracellular Ca, PKC enhances NMDA currents - New synaptic (dendritic) spines grown
- Protein synthesis
if ___ is blocked by anisomycin, LTP decays within a few hours of the tetanus stimulus
protein syntehsis
long term depression results in a
long term decrease in synaptic strength
when Shaffer collateral-CA1 synapses are stimulated at a low rate (1 Hz) for long periods (10-15 min) what happens?
EPSP is depressed for several hours
Can LTD effect LTP?
-LTD can erase LTP, and vice versa
____ is not avaialble to conciousness
nondeclarative memory
• Working memory is the ability to hold & manipulate information in mind for___ to ___ while it is used to achieve a particular goal
seconds to minutes
what are 3 important areas for declarative memory
- hippocampus
- medial temporal lobe structures
- midline diencephalic regions
___ is a model for declarative memory
LTP
Pyramidal CA3 neurons in hippocampus send axons (Schaffer collaterals) to synapse on___
pyramidal CA1 neurons.
Ltp
A baseline recording is established by providing a low-frequency & low-intensity stimulus such as when
only ampa receptors are activated
pathway 1 – high frequency and high intensity stimulus
pathway 2 – low intensity and low freqeuncy stimulus
what is observed in pathway 1?
ltp
a strengthening of the EPSP after returning to the low-frequency & low-intensity stimulus
add AP-5 or MK-801 during tetatnus. what effect on ltp?
these are ndma anatagonist so block ltp
add AP-5 or MK-801 after tetatnus. what effect on ltp?
ltp occurs
NMDA receptor activation is required for ___ of LTP.
INDUCTION
: PKC and CaMKII diffuse across synapse and cause
enhanced release of glutamate after terminal depoalrization
PKA and CaMKII increase AMPA receptor currents by insertion of ___
additional AMPA receptors
PKC and PTK increase ___ currents.
NMDA
long-term LTP in hippocampus requires ___ and ____
gene transcription and protein translation
how are kinases involved in ltp?
- kinases diffuse to the CA1 cell nuclei influencing genes that trigger long- lasting post-synaptic modifications
- In the presynaptic terminals kinases influence genes that cause presynaptic structural modifications (not shown).
Electron microscopic studies show that LTP induction causes an increase in the numbers of ___ on dendritic shafts
synapses
ltd is dependent on
nmda receptors
ltd is specific to
input
how do ltd and ltp differ?
- with ca signals
ltp – kinases are activated
ltd – phosphatases are activated
- ltd is associated with itnerlization of ampa receptors
ltp is associated with the ___ of ampa receptors
insertion of ampa receptors into postsynaptic membrane
ltd is associated with the ___ of ampa receptors
internalization
weak stimulation in CA1 (Ltd) results in ___in intracellular calcium
small increases
this leads to activation of phostpahatse
ltd or ltp involvs activation of phosphatases?
ltd
