Week 6: Memory Systems Flashcards
What is learning?
the process
What is memory?
the outcome
What are the 3 memory stages?
Encoding = acquisition and consolidation Storage = permanent representation is stored Retrieval = retrieved back into conscious awareness
What are the 4 types of memory?
Sensory
STM & Working
LT Non-Declarative
LT Declarative
What is LTM?
LTM has no limit and may last a lifetime
Declarative is the conscious type e.g. who is the PM
Non-declarative is the unconscious type (just do it)
How do you increase STM capacity?
Try to avoid decay through chunking
What is habituation?
decrease in response with repeated exposure
What is sensitisation?
increase in response with repeated exposure
How is the MTL important for memory?
Hippocampus, parahippocampal, entorhinal and perirhinal cortices make up the MTL
Damage can result in amnesia
What are the subcortical structures that are important for memory?
Fornix
Mammillary bodies
Anterior thalamic nuclei
Amygdala - which encodes content of experiences (fear learning)
What are the cortical structures important for memory?
Prefrontal cortex - storage and retrieval, episodic memories
Inferotemporal cortex - storage of visual observations
Why is the cerebellum important for memory?
Important for conditioning (e.g. Pavlov)
Activities such as riding a bike
Why is the striatum important for memory?
Has the basal ganglia, important for implicit (non-declarative) memories and habit formation
What are the 2 domains of sensory memory?
Echoic - auditory - 9-10sec
Iconic - visual - 300-500ms
What is the modal model of STM?
By Atkinson & Shiffrin
Sensory input –> sesnory register –> short term storage with the assistance of attention –> Long term storage with the assistance of rehearsal
Info can be lost at the short-term storage stage through decay or interference
What are the 3 components of the Baddeley & Hitch 1974 Working Memory Model
Central Executive
Phonological Loop: acoustic code, acoustic store and articulatory loop
Visuospatial Sketch Pad (VSSP): visual or visuospatial code
What are the regions responsible for phonological working memory?
Supramarginal gyrus - phonological WM
Premotor region - rehearsal in phonological loop
What are the regions responsible for VSSP?
Bilateral parietal occipital region
What is the story of HM?
Had a bilateral resection of MTL for epilepsy which included the hippocampus and amygdala
Led to severe anterograde amnesia and retrograde amnesia of up to 2 yrs prior
However he had a spared STM and non-declarative memroy
True or False
Amnesiacs can show normal implicit learning and non-declarative knowledge
True
What is Global Cerebral Ischemia?
Interruptions of blood supply to the brain
Can lead RB to dense anterograde and retrograde amnesia of approx. 1-2yrs
What is Transient Global Amnesia?
Disruption of blood flow to MTL and diencephalon
Is a short term syndrome of 4-6hrs
Lead to sudden anterograde and variable retrograde amnesia 24-48hrs
What is Korsakoff’s Syndrome?
Is caused by chronic consumption of alcohol.
Dorsomedial nucleus of thalamus and mammillary bodies are implicated in the syndrome
It is the result of a thiamine deficiency
Leads to severe anterograde & retrograde amnesia: ret is more effected and disrupted and greater loss of declarative
Explain Alzheimers Disease
The first symptom is minor loss of memories but becomes more extreme
Pathological changes include Amyloid plaques and neurofibrally tangles; degeneration of basal forebrain and reduced acetylcholine
