Chris Bailey Lecture Flash Cards
What are motor skills and what sub class are they part of?
Skills like riding a bike and walking, skills we have learnt but have become subconscious of Part of procedural subclass of memory
What three sub classes can memory be divided into?
Declarative
Emotional
Procedural
What is a priming cue?
If something happened in the past, a past memory makes you hate for example the smell of something, a past memory triggers/ cues an emotional feeling. It's in the subclass of procedural memory
What is declarative memory?
A type of long term memory involved in recalling facts and knowledge, words and meaning, history and episodic memory which stores specific daily experiences.
What is procedural memory?
Another type of long term memory (declarative the other type)
It’s involved with unconscious memory such as skills, eg riding a bike, puzzle solving, walking
What is emotional memory?
To do with preferences and aversions
Eg having a strong like or dislike to something
What Part of the brain is mostly involved with emotional memory?
Amygdala
Hypothalamus
What part of our brain is mostly involved with declarative memory?
Hippocampus
Which part of our brain is mostly involved with procedural memory?
Cerebellum
Striatum
Brain stem and spinal motor output
What are the areas called collectively that control memory?
The cortical association areas of the brain
What was the name of the man who had epilepsy, who had his entorhinal cortex, hippocampus and amygdala removed to try and cure his epilepsy? What did this result in? What are these parts of the brain all a part of?
Henry Molaison (H.M)
Had his whole temporal lobe removed
This resulted in memory loss.
Indicated that the entorhinal cortex, hippocampus and amygdala are all involved with memory.
His short term memory was still in tact, and working memory too, but he couldn’t form new long term memories.
Therefore we knew the hippocampus was important in making long term memories stick.
What is the engram- Hebbs law?
When two neurones are active, so that one repeatedly releases neurotransmitter at the same time as its post synaptic partner is firing action potentials, then that synapse will become STRONGER. The synapse is strengthened by this intense activity.
Memory depends on populations of interacting neurones
The pattern of strengthened synapses defines memory.
How do we study synaptic strengthening?
We use a rat temporal lobe slice
We stimulate glutamate excitatory axons
And then record membrane potential of neurones
What is the increase in strength after repeated stimulation called?
Long term potentiation ( LTP)
This strengthened action potential stays around for months and is the basis of long term memory
What needs to be reached for long term potentiation of memory to be achieved?
A threshold,
EPSPs produced by a High rate of stimulation summary together and reach the threshold, ie a synapse stimulated repeatedly
What two things can prevent LTP?
Pharmacological blockade of NMDA receptor
Reducing extracellular Calcium levels
These result in EPSP not potentiated
What does removal of Mg2+ from the NMDA receptor channel allow?
Allows both calcium and Na+ to flow through the channel
Calcium entry into the cell results in cellular changes, which leads to increased AMPAr responses and therefore LTP
What Is Mg-dependent gating very important in?
Synaptic plasticity, learning and memory
What relieves the Mg2+ block of the NMDAr receptor?
Repetitive activation of AMPA r results in increased extracellular calcium levels. This causes depolarisation and therefore relieves the Mg2+ block of the NMDA receptor.
How can we increase LTP postsynaptically?
More AMPAr’s
More sensitive AMPAr
More synapses
How can we increase LTP presynaptically?
Increase release of glutamate from releasing synaptic vesicles
Increased release sites
More vesicles
What is classical conditioning to do with?
Animals
If you ring a bell- no salivation
If you give food and ring a bell - salivation (classical conditioning)
Then if you ring the bell again with no food- salivation
Food is the unconditioned stimulus, the sound of the bell is the conditioned stimulus.
It is the learning in which the conditioned stimulus (bell) comes to signal the occurrence of a second stimulus, the unconditioned stimulus (food).
Salivation is the unconditioned response
What is the unconditioned stimulus in fear conditioning?
Pain (electric shock)
Again a bell is the conditioned stimulus.
The animal learns that when it hears the bell it will get an electric shock, therefore it freezes.
Conditioning is usually done by pairing the two stimuli, as in Pavlov’s classic experiments.
What drug addiction can pavlovian classical conditioning be linked to?
Cocaine
People get off it, then something, a memory trace, eg seeing somebody else have it, may trigger them to start it again.
We’re looking to erase this memory trace with drug treatment to cure drug addicts, need to block these cues.
___________ a memory will strengthen it..?
Reactivating!
Stimulants are cognition (memory) enhancers. Examples?
Amphetamine
Caffeine
Methyl phenidate
AMPAkines are cognition enhancers. Examples?
Positive AMPA-r modulators
Piracetam
IDRA-21
Difference between retrograde and anterograde amnesia?
Retrograde amnesia: where most memories created prior to the event that caused amnesia are lost while new memories can still be created.
Anterograde: loss of the ability to create new memories after the event that caused the amnesia, but not lost memories that were created prior to the event that caused the amnesia.
What’s the percentage chance of developing Alzeihmers if you’re over 95?
53%
Which artist drew pictures to show his descent into Alzeihmers?
William Utermohlen
Is Alzeihmers cortical or sub cortical?
Cortical
Parkinson’s is cortical
Which part of the brain deteriorates in early stages to cause memory and speech defects?
Early damage in entohinal cortex
What are Neuritic plaques made of?
Amyloid-B-protein
They’re extracellular
What are neurofibrillary tangles made of? (Alzeihmers)
Made of abnormal cytoskeleton protein: Tau
They’re intracellular
What do plaques and tangles effect? (Alzeihmers)
Primarily Affect glutamate and acetylcholine neurones and terminals
This results in synapse loss and neuronal death, which leads to brain shrinkage
Abnormal ___ processing results in formation of _____plaques
Abnormal APP processing,
Results in formation of amyloid plaques
What causes the formation of an amyloid plaque?
Abnormal cleavage of APP (amyloid precursor protein) by the enzyme BETA-secretase
Cleavage products are AB40-42 and soluble APPbeta
AB40-42 levels build up and aggregate
Aggregation enhanced by ApoE4
Forms amyloid plaque
Are low or high levels of Abeta40/42 found in the brain of a healthy person?
Low levels!
Normal cleavage of APP does not result in Abeta40/42 normally, only with abnormal cleavage leading to plaques.
What is aggregation of AB40/42 enhanced by to form a plaque?
ApoE4
What enzyme cleaves APP to cause formation of amyloid plaques?
Beta secretase
What enzyme cleaves APP in a normal healthy brain?
Alpha secretase
What enzyme cleaves off the extra chain (AICD) on the AB40/42 molecule to form AB40/42 alone?
Gamma- secretase (y-secretase)
What’s a Genetic risk factor in late onset Alzeihmers?
ApoE4 mutations: leading to increased aggregation