associative learning
As cells fire simultaneously they increase the synaptic associations. This results in networks of cells which are synaptically linked
Habituation
decrease in response (& NT release ) with repeated stimulus
like a background noise that you adapt to drown out
Sensitisation
increase in response with repeated stimulation – mediated by an interneuron
LTD
long term depression helps to avoid the whole brain potentiation
Short term memory is
1) a very brief memory (seconds) either from an external
stimulus or retrieval from a long term memory
2) easily displaced by another stimulus
3) Can be extended into working memory by
a) repetition in a phonic loop (temporal extension) or
b) chunking which links familiar chunks together to extend the size of chunk
how do we test short term memory
digit span 6-7 is normal
chunking
phone numbers
07979 635 815
Working memory
1) The maintenance and integration of information in an active state for a relatively
brief time in order to achieve a short term task or goal
2) Is comprised of a mixture of short and/or retrieved long term memory
Working memory
1) The maintenance and integration of information in an active state for a relatively
brief time in order to achieve a short term task or goal
2) Is comprised of a mixture of short and/or retrieved long term memory
what is the definition of working memory
As Short term memory only lasts a few seconds it must be repeatedly re-activated, its reactivation and subsequent duration
what are the subdivisions of LTM
- declarative memory
- non-declarative memory
what are subdivisions of declarative memory
this is conscious !!!
- semantics (language/facts)
- episodic (events/experiences)
non-declarative or implicit taxonomy
- procedural
- priming
- associative learning $
what are the 4 parts of learning
- encoding - memory creation
- storage - persistence memory traces
- retrieval - memory recovery
- consolidation - strengthening of memory traces
memory formation
A) A series of events are encoded by the hippocampus, and a reference is made to their memory location – hippocampal index (File Allocation Table)
B) If this information is recalled prior to consolidation, the hippocampus performs the retrieval from its index of the events
C) After consolidation of the memory retrieval can be initiated directly from the sensory cortices
consolidation
this is where there are structural changes at the synapse, LTM us associated with changes in connectivity in networks of neurons predominantly in the cortex
what is the basal ganglia pathway for non declarative memory
Corpus striatum (part of Basal ganglia) = caudate nucleus + putamen – thought to influence memories involving movement & procedural memory e.g. Olympic diving Cerebellum – influences fine motor learning including speech movements
Retrograde Amnesia
before event
Anterograde Amnesia
after event
Lesions in either the anterior or dorsomedial nuclei of the thalamus, or in the Mammillary bodies can cause
anterograde amnesia
dorsomedial nucleus of the thalamus receives input from
temporal lobe structures (like the amygdala of the limbic system) which is then relayed almost exclusively to the frontal cortex (executive function).
