Memory Flashcards
Define Primary Memory according to William James
A portion of present space of time
Linked to conscious experience
Retrieval is effortless
Define Secondary Memory according to William James
Genuine past
Unconscious - permanent
Retrieval is effortful
Atkinsons Shiffrens Modal model of Memory
Describe Sensory Memory
- sensations persist after the stimulus has disappeared
- decay’s rapidly, yet there are stores for visual(iconic) and auditory(echoic) sensory info.
Sperling’s Experiment for Sensory memory
- matrix of letters for 1/20 seconds, recall the letters after
- sounded low, medium or high tone immediately after matrix disappeared
- the tone signalled 1 row to report
- recall was almost perfect
- memory for images fades after 1/3 seconds, making report of entire display hard to do
What is working memory?
- a temporary store for information needs to be rehearsed/ encoded to become long term memory
- this is said to have a limited capacity
Baddeley and Hitch’s working memory model
- Baddeley found error in Atkinson & Shiffrin’s model
- completing multiple tasks whilst remembering numbers, didn’t seem to affect the error in the number of digits remembered over a period of time.
- B&H argued that the working memory must comprise different components
- Visuospatial Sketch pad
- Central Executive
- Phonological loop
What is the evidence for the Phonological loop?
The Phonological similarity effect Baddeley (1966)
- list of 5 words to be recalled
- showed a large effect of phonological similarity, there was no effect of semantic similar
- the greater the number of syllables the worse the recall, even if the list is shorter
Impairment of the phonological loop
- some patients have been described who have severely reduced verbal spans for all types of unconnected items
- they still have intact word perception
- no problem with speech production
- lesion near the Sylvian fissure, near the parietal and temporal loop can impair the phonological loop
- as the contents are actively refreshed by an articulatory process (sub-vocal speech) disrupting this process results in poor retention in the phonological loop
The Visuospatial Sketchpad and the evidence for it
- necessary for holding online a sequence of visually guided actions
- necessary for ‘seeing in the mind’s eye’
De Renzi & Nichelli - 1975
- some patients with brain damage had impaired digit spans and some had impaired spatial spans
- the “double dissociation” gave evidence for independent processes
Logie -1995
- Visual cache: passively stores visual info about form and colour
- Inner scribe: stores spatial and movement information and can rehearse the contents of the visual cache
Della Sala et al., - 1999
- Viewing abstract pictures interfered with the visual task, whereas tracing the outline of a series of pegs on a board interfered with the spatial task
What other components have been added to the Baddeley & Hitch Working Memory Model
- Fluid Systems
- Visuospatial sketchpad
- Episodic buffer
- Phonological loop
- Crystallized systems
- Visual semantics
- Episodic LTM
- Language
Craik & Lockhart 1972 ‘Levels of processing’
- participants asked to make judgments about words based on
- Orthographic information
- Phonological information
- Semantic reasoning
- recall improved with each orienting task
- shows that deep coding or elaboration is one of the best ways to learn new material
- is memory strong because encoding was “deep” or do we infer that strong memories must have been “deeply encoded”?
Roediger & Karpicke 2206: Study-test vs study-study
- Advantage for the study-test conditions after delay
- Note: no feedback was provided in the “test” conditions
- Studying and then testing yourself leads to much better retention
Encoding and Retrieval
Morris et al., 1977
Godden & Baddeley - 1975
What is Amnesia
Damage to the medial temporal lobes and closely connected regions (Thalamus, fornix) is often the cause
Anterograde amnesia: when the ability to take in new information is severely and often permanently affected
- intelligence is intact, attentional span is intact, personality is unaffected
Retrograde amnesia: difficulty retrieving memories established prior to the cause of the neuropathology
- both forms of amnesia often found together but can present individually
Procedural memory
- memory not detailly available to the consciousness
- involve skills and associations that are generally acquired and retrieved at an unconscious level
- thinking about how to perform these automatic activities might actually disrupt the ability to perform the activities, to begin with.
- Amnesiacs can learn new skills in this way
- Mirror Tracing (Corkin- 1968)
- Mirror Reading (Cohen & Squire- 1980)
subiculum (Latin for “support”) is the most inferior component of the hippocampal formation. It lies between the entorhinal cortex and the CA1 subfield of the hippocampus proper.
What are the inputs and outputs of the Hippocampus?
Inputs
- multiple areas of the cerebral cortex, especially prefrontal, cingulate, temporal lobe and amygdala, olfactory bulb
- these project via the entorhinal cortex and into the hippocampus via the subiculum
Outputs via the subiculum
- prefrontal cortex, amygdala, septal nuclei, nucleus accumbens, mammillary bodies, anterior thalamus, hypothalamus
- the fornix is a major output pathway
How is the Hippocampus organised? and how does this affect its function?
Organized in layers, lateral and medially
: perforant pathways, Schaffer collaterals, mossy fibres, pyramidal cells and granule cells
What other cortices are involved in memory and what is their function?
- Prefrontal cortex (dorsolateral)
- working memory, online, effortful
- Parahippocampal gyrus
- recognition memory, scenes (PPA)
- Other Temporal cortices
- categorical memory,
- word recognition for words,
- objects / faces (FFA)
- Association cortices
- semantic memory
- frontotemporal dementia semantic variant
Describe the location and structure of the Amygdala
found in the medial temporal lobe anterior to the hippocampus
- basolateral complex
- sensory input
- associative learning
- central nucleus
- visceromotor outputs – hypothalamus, PAG
- orbitofrontal cortex
- anterior cingulate
What neurotransmitter is involved with emotions?
Dopamine: Reward
- Mesolimbic system
- ventral tegmental area to the ventral striatum, prefrontal cortex etc
Noradrenaline: Aurosal
- Locus coeruleus:
- thalamic gating
- the amygdala, the hippocampus – memory enhancement
- cortices - attention
- Aurosal
- alertness, stress reactivity
- attention, activation
- behavioural salience
5HT: Serotonin: vegetative functions
- Raphe nuclei to the subcortical centres and the cortex
