Cognitive Neuroscience - Learning and Memory Flashcards
How has amnesia been used to study memory?
Looking at patients with different types of brain damage - usually to hippocampus via closed head injury or bilateral stroke
Other areas are often damaged however so some data is limited
What is the function of the hippocampus?
Activated in autobiographical memory studies + damage = poor performance; episodic memory, more active in the actual retrieval process than thinking about it once retrieved
Activation similar for recent and remote autobiographical recall (though emotion/detail of recent may confound)
Holds a spatial map of the environment ie right hippocampus = spatial map; left = context
Future planning
What evidence is there for the future planning role of the hippocampus?
Possibly a role of the R hippocampus
Greater activity when imagining the future
Patients KC and DB - inability to imagine the future (though brain damage not restricted to hippocampus)
However future simulation also requires - details from episodic memory and their recombination to form a simulation then encoded into a memory
What kind of memory impairment arises from frontal lobe damage?
More selective deficit compared to MTL
Unknown if deficit in encoding, retrieval or both - brain damage = hard to tell
What is confabulation?
Production of fabricated accounts of events = blend of facts/memory/memory failure/imagination or dream even
Spontaneous or provoked
Following damage to the frontal lobes - ventromedial prefrontal cortex damage is sufficient, even when damage elsewhere is minimal
What does confabulation tell us about the mind?
Evidence for the importance of the frontal lobe in retrieval - info available but chronology is not
It also highlights the confidence we have in our own memories (people find it hard to reject) and how they are difficult to (consciously) edit
How is the parietal cortex involved in memory and what are some problems studying it?
Involved in recollection in brain imaging but lesions do not produce recollection deficits…
However -Neuroimaging = correlation not causation
Damage = subtle and therefore not picked up on all memory tests
What do EEG studies tell us about encoding and retrieval?
Both components are highly overlapping
Orienting (how nice is turtle?!) + memory tasks - comparison of ERP data between hits and misses:
Evidences preparatory processes - brain gearing up before stimulus presentation and encoding, depends on stimulus type (visual auditory linguistic etc) and task demands (recognition recall etc)
Evidences old/new effects - feature of recognition memory ie has this word been presented before or not? Claims to be consistent with dual process models for memory (ie familiarity/FN400 mid frontal/graded vs recollection 700ms/Left parietal/context judgements)
What is a plurals task and what do findings demonstrate?
Present a series of words at study that may or may not be plural
Act test present same words some plural some singular - mix of the same as and different to study
Old words - left parietal + mid frontal old/new effects
Similar lures - mid frontal old/new effects only
What control do we have over retrieval?
We can use in task strategy - reliant engagement from prefrontal cortex (? Left)
Pre-retrieval processes - preparatory processes or retrieval orientation and early selection of information (Vs late correction)
Post-retrieval processes - other control processes from the PFC ie late-frontal old-new effect? (But less well studied)
Use of strategy can be limited in memory tasks by presenting accurate and inaccurate instructions: if there has been an effect of preparatory processes this will help distinguish and eliminate
What processes occur at retrieval?
Retrieval mode - a general ‘state’ entered into when memory retrieval is needed; difference between type of memory retrieved
Retrieval orientation - a more specific state than a retrieval mode; constraint processing of retrieval cues based on task demands ie test items compared to retrieval cue - if matching, more likely a target word is old rather than new; retrieval cues also help distinguish between classes of items - living/non living - and so further narrows your search
What is a basic ERP paradigm for assessing retrieval orientation?
Words studied with 2 orienting tasks - is this word found in Sheffield? Rate this word for familiarity?
Use of exclusion task - only need to recognise words/say ‘old’ for words studied on one of the orienting tasks - presented with a list of targets/non-studied lure aka foil/studied lure aka foil
Targets and studied foils should have equal familiarity
Assume - people adopt a retrieval orientation - people will compare items in the list to a specific retrieval cue, this cue will reflect the encoding task; lack of match to cue suggests word is old
For the new foils at task - you essentially perform the study task at test, asking the same question you would have at study
What are some findings from ERP retrieval orientation paradigms?
For non studied foils - you see the same ERP waveforms you would see if the words had been studied at study; test becomes a study phase for these foils
Evidences the difficulty in separating encoding from retrieval
What are some behavioural studies and findings for retrieval orientation?
Memory for foil paradigms - deep vs shallow orienting tasks at study
Two tests at test phase - one w/deep one w/shallow
(LoP account = deep>shallow)
Second test phase - Foils from deep/foils from shallow/new foils - which foils were presented before? (Both deep/shallow should be equally familiar)
Deep foils>shallow foils> new foils - deep foils were assessed for meaning in test phase 1 meaning better encoding and retrieval in test phase 2
What do findings from behavioral and ERP studies on retrieval orientation tell us?
Convergent evidence - people do adopt a retrieval orientation woo!
