Learning and memory Flashcards
Learning
acquisition of experience
Memory
- retention of experience
- storing aspect
Nature
- called declarative memory
= ‘explicit’; the what
- i.e what is the capital or itlay → Rome
- Consciously aware
- Able to describe in words
- Fades with time → use it or lose it
Types of declarative memory
Semantic
- facts
- “capital or Italy”
Episodic
- for events
- memory
- what happened at your birthday
Non declarative
what name of memory, skills
‘implicit’ → the how
- things like skills, habits, behaviours
- piano, typing, skiing
- less likely to fade
- learnt to drive, pick it up after 10 years skills won’t fade
Types
- Procedural memory
- skills and habits
- e.g motor tasks
What are the other types of memory
so not declarative and non declrative
Conditioned responses (Associative reflexes -> pavlov)
Emotional responses
- how do we feel in a particular environment → can invoke an emotional response in us
How long is the duration of snesory memory
very short seconds
Duration of STM
30 seconds
Capacity of STM
7 +/- 2
How do we retain infomation
what store does it go to and what needs to happen
- goes to LTM
- via consolidation
- when you sleep, you also consolidate things
- need to sleep
Reterograde amnesia
- forget events before the trauma, but can store info after
- typically affects declarative memory not non declarative
despite what films tell you, it’s usually not complete
What is ribots law
recent memories are more likely to be lost than older memories
you know like wattpad books when the girl forgets the guy she was with prior to the traumatic incident but remembers the boyfriend that cheated on her 5 years ago and still loves him
What is anterograde amnesia
Inability to form new memories from that point onwards
How do we know that the two processes of memory are different
its because of how reterograde and anterograde amnesia work
-tells us that acquiring and retaining memory are two diffferent processes
How has our understanding of memory developed over the years
how have theories chnaged, and what do we believe know
- Lashley (1920s)
- Experimental lesions
- said that every part of brain is involved in memory
- Lettvin (1960s)
- The grandmother cell hypothesis
- every neurone is involved
- Currently
- fMRi and lesions→ looked that there is multiple region bur the whole brain isn’t used
Where do we process declarative memory
Medial temporal lobes
hippocampus, neocortext
semantic and episodic - you can say it
How does declarative memory get stored
so pathway in brain
- declarative memory
- travels via fornix
- hippocampus → hypothalamus → thalamus → neocortex
- if you cut fornix do not that get that conversion
e.g if you korsakoffs
- there’s a selection lesion of some hypothalamic neurones
- they give rise to loss of episodic memory
Where is the anatomical location of procedural memory
Where?
- cerebellum: crucial for determining coordination of sequences in muscles to allow smooth movement
- supplementary motor area & basal ganglia
- Emotioanl types of associated with the amygdala
people with parkinsons find it hard to pick up new motor skills, even though it associated with a later onset
What part of the brain is working memory located in
Involves the prefrontal cortex (+ other nuclei)
-attention occurs here
so can have a problem with working memory, but no problems with declarative memory
- the evidence: from people with ADHD, schizophrenia
HM had a bi-lateral temporal lobectomy, what memories where affected
- Bilateral temporal lobectomy
- to cure his seizures
- hippocampus and amygdala
- Severe anterograde amnesia for declarative memories
- he could not require or remember new info
- Childhood memories intact
- could tell you an out
- temporal lobe for new declarative but not old memories
- Procedural memory?
- no problems
- why? done is the cerebellum, basal ganglia miles away from temporal lobes
- so HM could still play the piano
How do neurones store memories
basic level not mechanism
Neuroplasticty
-neurones work in networks
-they release neurotransmitters, and then recognise neurotransmitters
-so they do it by
- Change in neurotransmission
- change in synaptic structure
Mechanism of how neurones store memories
long term potentiation
change in the level of neurotransmission in synapses -> synaptic activity is increased (potentiated)
- Presynaptic neurone is releasing a bit of its NT (glutamate)
- glutamate binds onto AMPA
- causes depolarisation post synpatic neurones
- normally glutamte would bind onto the NDMA receptors, but nothing would happen
When there is intense stimulation
1. Glutamate is still being released.
2. AMPA receptors are also still be activated
3. NMDA are also being activated as they have been unblocked.
4. LTP relies on activation of NDMA receptors -> causes chnage in post synpatic neurone
5. NDMA receptors allow calcium to enter cell whereas AMPA doesnt
6. This activates kinase enzymes
7. causes phosphorylation of various proteins in neurone like AMPA receptors to allow more glutamate
What is happening at the synpase
Change in physical structure
1.Normally, pre-synaptic neurone makes 1 synapse with the dendrite of a post-synaptic neurone
2.when levles of activity change at pre-synpatic neurone, a new synpase forms
3.so presynpatic pre-synpatic neurone has more influence on post synpatic neurone
4.intense stimulation leads to learning
What are the differences between rigid and plastic neurones
synpases are either rigid or plastic
-Learning, acquisition and storage of information requires plastic synapses (like the ones mentioned)
-As the brain ages rigid synapses do not decline in number but there is a decline in number of plastic synapses.
parts of brain that process sensory infomation have rigid synpases
How can we enhance memory
pharmacological and non pharmalogical
**- Pharmacological: enhancers
**- Enhance learning and memory
- can use nootropics
- can be used in alzehimers by enhancing cholonergic transmission
- doesn’t work in people who have normal memory function
**- Pharmacolgical: Suppressors
** - Drugs that interfer NDMA receptors i.e NMDA antagonists eg ketamine
- can makes people forget
- Non-pharmacological
- CBT reactivates synpases and can change activities of synpases
- benefical in people who have PSTF, as memories have severe impacts on quality of life
