Memory Flashcards
Basic principles of memory Neuropsychology of memory Synapse plasticity
Who came up with the early distinctions of memory and what two types of memory did they say there were?
William James, primary and secondary memory
Describe primary memory
Portion of present space of time, staying online, linked to conscious experience, retrieval is effortless
Describe secondary memory
Genuine past, unconscious/permanent, retrieval is effortful
Who came up with the modal model of memory?
Atkinson and Shiffrins
Describe the stages of the modal model of memory
Stimulus enters sensory memory, is forgotten or is given attention to enter short-term memory, is forgotten or rehearsed to encode it into long term memory, from where it can be forgotten or retrieved into STM
What is sensory memory?
Sensations persist after the stimulus has disappeared but are subject to very rapid decay
What type of stores exist for sensory memories?
Iconic store for visual sensory information and echoic store for auditory sensory information
Describe Sperling’s experiments and his findings
Presented matrix of letters for 1/20 seconds and asked subjects to report as many letters as possible, could only recall a few, not because they didn’t have time but because the memories decayed very quickly. Was easier when they were told to just remember a row. Showed that we take in a lot of information but most of it disappears very soon
What is the working memory model?
Baddely & Hitch claimed that short-term memory is used for problem solving, reasoning and thinking about things rather than just information keeping. They demonstrated this by getting subjects to answer true/false Qs while they had to remember a few digits - found that reasoning time increased with digit load but error rate did not increase
What are the parts of the working memory model?
The central executive which sends things to/controls the visuo-spatial sketch pad and the phonological store, which is strengthened by an articulatory loop
What is the evidence for the phonological store?
Phonological similarity effect - showed lists of 5 words to write down in order, with one sounding similar, one random, one meaning similar things. People got confused when words sounded the same (rat, cat, mat etc), while semantic (meaning) similarity had no effect. The longer the words the harder it was to remember.
Patients with lesions in the left hemisphere affecting the parietal and temporal lobes have severely reduced verbal spans while they have intact word perception and no problems with speech production.
What is the phonological store?
Acts like a tape recorder for a limited time, with the contents actively refreshed by an articulatory loop. Disrupting this loop results in poor retention in the phonological store
What is the visuospatial sketchpad?
necessary for holding online a sequence of visually-guided actions and for seeing in the mind’s eye
What is the evidence for the visuospatial sketchpad?
De Renzi and Nichelli showed some patients with brain damage had impaired digit spans and some had impaired spatial spans - double dissociation was evidence that these were separate problems.
What parts can the visuospatial sketchpad be split into?
The visual cache - passively stores visual info about form and colour
The inner scribe - stores spatial and movement information and can rehearse contents of the visual cache
How did Logie prove the existence of the visual cache and the inner scribe
Got healthy individuals to do a spatial task (block tapping task) and a visual task (remembering patterns) and found that viewing abstract pictures interfered with visual tasks whereas tracing the outline of a series of pegs on a board interfered with the spatial task
What is encoding?
Changing information into a way which can be stored in the brain and recalled.
Describe Craik and Lockhart’s level of processing concept
The basic idea is that memory is really just what happens as a result of processing information. Memory is just a by-product of the depth of processing of information, and there is no clear distinction between short term and long term memory.
The more you process information the better it sticks in your memory. The types of processing include orthographic (the way a word looks/is spelt), phonological (the way a word sounds), and semantic (the meaning)
Which type of processing is shallowest and has the worst retention?
Orthographic
Which type of processing is deep and has the best retention?
Semantic
Describe Craik and Lockhart’s experiments about processing and recall
Participants were asked to make judgements about words - upper or lower case? rhyme with hat? does it fit into the sentence the cat sat on the…? then given a surprise memory test. Found that processing information, not encoding it, leads to durable memories
Is repeated exposure of information enough to remember and recall it?
Repeated exposure of something is not enough to remember it e.g. the American coins. For information to stick it has to be processed
What is the best way to learn new material?
Deep encoding or elaboration
What did Roediger and Karpicke’s study show?
They showed that studying then testing the information led to better retention and recall than studying alone. Retrieval practice effect.
What is the retrieval practice effect?
Retrieving information and putting it into practice makes for much better information retention.
What did Morris show in his study on encoding and retrieval?
Gave evidence against the levels of processing. They said that it is possible that the better recall of meaningful material is due to the way the participants memories were tested. Morris et al (1977) found that if participants were given a rhyming recognition test they remembered the words which had received shallow processing better than the more deeply processed ones. A shallow task might be better if the retrieval uses the same type of processing as encoding
Describe Godden Baddeley’s context dependent memory studies
Taught divers lists of words on land and sea and found that they recalled it better wherever they were taught it. Memory depends on context of learning and testing
Describe state dependent memory
Recalling information is stronger when the mood they are in when recalling matches the mood they had when learning
What is amnesia?
Intact intelligence, intact attentional span and short term memory, unaffected personality, but ability to take in new information is severely and usually permanently affected
Describe Scoville and Milner’s studies
H.M. lost the ability to form new memories following a bilateal removal of his medial temporal lobes. He could do a task, and even comment that it seemed easier than he expected, without realising that he had done it hundreds of times before. His anterograde procedural memory was totally affected. He also lost his memory for events that had happened after his surgery: he could not remember moving house, nor that he had eaten a meal thirty minutes previously. He had also suffered some retrograde amnesia of events preceding the surgery, such as the death of his uncle three years before. However, his early childhood memories remained intact. His intelligence also remained as before, at slightly above average.
What did HM’s surgery involve?
Bilateral removal of his medial temporal lobes including the hippocampus
What is amnesia usually caused by?
Damage
What is amnesia usually caused by?
Damage to the medial temporal love or anatomically connected regions. Can occur in head injuries, Alzheimer’s disease, epilepsy and stroke.
What is anterograde amnesia?
Amnesia following brain injury, where episodic memories are severely affected
What is declarative memory?
The conscious, intentional recollection of factual information, previous experiences and concepts
What is implicit memory?
Unconscious memories such as skills (e.g. knowing how to get dressed, eat, drive, ride a bicycle without having to re-learn the skill each time).
What is episodic memory
The memory of autobiographical events (times, places, associated emotions, and other contextual who, what, when, where, why knowledge) that can be explicitly stated or conjured. It is the collection of past personal experiences that occurred at a particular time and place. (time travel memory)
What is semantic memory?
Factual information. General world knowledge that we have accumulated throughout our lives.
What are priming effects?
A process whereby subjects are measured by how they have improved their performance on tasks for which they have been subconsciously prepared
What is procedural memory?
A type of implicit memory (unconscious memory) and long-term memory which aids the performance of particular types of tasks without conscious awareness of these previous experiences. When a skill becomes automatic, it can operate in the absence of awareness
How is the procedural memory of an amnesiac affected?
Amnesiacs can learn new skills even though they do not remember learning those skills (procedural memory but no episodic memory) e.g. mirror tracing (Corkin) and mirror reading (Cohen and Squire)
What evidence is there for different types of memory systems?
Butters et al - pursuit-rotor task where healthy controls and patients with Alzheimer’s disease showed normal learning (implicit memory) whereas patients with Huntington’s disease were impaired, so can see that procedural memory is independent to other memory systems.
Where is procedural memory in terms of anatomy and which disease is it impaired in?
Basal ganglia, so is impaired in Huntingdon’s disease.
Describe Warrington & Weiskrant’z priming experiments
Got 5 amnesic participants to identify degraded pictures, showed long term memory improvement even though they had no idea they’d been tested previously
How is an amnesic’s semantic memory compared to their episodic memory?
Intact semantic memory (what stuff is, facts, meanings) but bad episodic memory (memory of when and where and what events have taken place) - e.g. can’t remember what they had for breakfast but know what ‘breakfast’ is
Where are declarative (episodic and semantic) memories acquired and retained short-term?
In the medial temporal lobes
Can new semantic memories form despite amnesia?
Bayley et al - say NO, tested new vocab in 2 adult amnesics with fake words and new words, found that they couldn’t remember it
Vargha-Khadem say YES - three children with damage to hippocampus just after birth, have very poor episodic memories but have good knowledge, completed normal schooling, have good vocabularies
Sharon et al - when learning was incidental, yes. When explicitly asked to remember, no. Doesn’t support Squire’s declarative memory theory
Anterograde amnesia explicit memory
New episodic memories always impaired
evidence for new semantic learning is mixed
Learning is limited to certain special situations
What is retrograde amnesia?
Amnesia before brain injury. Some degree of retrograde amnesia is almost always present. Extent of retrograde amnesia for episodic memories is highly contested
What is the standard model of consolidation?
All declarative memories (episodic and semantic) depend on the medial temporal lobes for acquisition and short-term retention but over time become consolidated to other brain regions
Is episodic memory for the distant past intact in retrograde amnesia?
Bayley et al - yes, supports squire’s standard model of consolidation
Viskontas et al - no, does not support squires standard model of consolidation
Evidence for preserved remote episodic is mixed, some patients show very good recall - are these memories highly practiced and recalled by rote?
What is semantic dementia?
- impairment of semantic memory
- usually lesion associated with lateral temporal cortex
- poor knowledge of meaning of words or concepts
- naming difficulties - including semantically related errors e.g. dog for rabbit
- not confined to one modality - deficits can include difficult recognising sounds e.g. doorbell or telephone
Frontal lobes and memory
Janowsky - 7 patients with frontal lobe lesions, learned 20 trivial facts, then tested after 6-8 hours.
If correct, where did you learn this?
the patients were only impaired in their ability to identify where they had learnt information, not in the memory store per se but the control part of the memory, e.g. where it happened, when and where to store it etc
Confabulation
patients remember things that don’t happen and don’t exist but are very sure of their beliefs
Provoked confabulation
normal response to a demand for information which is not available e.g. saying that items in a test have been shown before when they weren’t
Spontaneous confabulation
person acts on their erroneous memories e.g. tries to leave hospital because they have to go to work or cook a meal
usually a result of frontal lobe damage, not due to damage to memory storage
Caused by a breakdown in control processes e.g. monitoring whether retrieved memories are relevant now
