memory y1

How was HM’s memory impacted?

•  could retrieve LTM but not create new LTM → no hippocampus

  • had anterograde amnesia + temporally graded retrograde amnesia

  • his amnesia suggests a distinction between encoding + retrieval

what is retrograde amnesia?

 a loss of memory-access to events that occurred, or information that was learned, before an injury or the onset of a disease

what is anterograde amnesia?

loss of the ability to create new memories after the event that caused the amnesia

research into LTM

pps shown up to 10k photos were able to recognise those seen previously with a 83% accuracy

outline research into sensory memory

• Sperling (1960): sensory memory is 50ms

  • 4.5 items is the span of immediate memory

  • its a memory limit NOT a perceptual limit e.g., letter flash task → you are aware there are other letters you cannot remember

broadbent memory model

we have 3 stores

1. S-system: sensory memory with unlimited capacity

2. P-system: limited capacity, items processed serially & can be fed back to the S-system with rehearsal

3. LTM

also used the filter model

sensory-selective filter-higher level processing- working memory

what is research support for primacy and recency?

Glanzer & Cuntiz

recreated Murdock, counting backwards after list ended

evidence to challenge primacy & recency

• Bjork & Whitten (1974): manipulated rehearsal for diff items but still found a primacy effect, still found recency effect when there was a number distractor task at the end of the list

• long term recency effects e.g., Baddeley & Hitch rugby study

  • also found interference

evidence folr decay/rehearsal

• Broadbent (1958): forgetting in STM is decay & forgetting in LTM is interference

• Brown (1958)

  • pair of consonants to remember then read pairs for 5s then recall

  • pairs of consonants to remember, wait for 5, then recall

  • when rehearsal is prevented, items decay and memory is lost

• Peterson & Peterson (1959)

  • three letters and numbers then recall

  • count backward in 3s from the number

• Brown-Peterson task: to examine forgetting when rehearsal is prevented by an irrelevant task

  • decay occurs even when the number of items is well below immediate memory span

evidence for interference

• Keppel & Underwood (1962): proactive + retroactive interference

• Wickens et al (1963): switching the category of the items e.g., letters to digits improved memory performance

• Waugh & Norman (1965): there is a greater contribution from interference than delay

Broadbent (1958)’s claims are not really supported as there is a support for a greater contribution of interference than decay in STM

what is the d prime?

• The distance between old and new distributions reflects item familiarity

• Curve for recognition of old items and one for new items, the overlap = d

• Take response bias into account

• line more right = more cautious, more likely to reject

• Line more right = more likely to accept so more liberal

• D’ = hits - false alarms

what is Cowan’s K value?

Working memory capacity = set size x d’

research support for the slots model

WM has a finite number of slots that can be filled

no research suggests slots in brain physiology

research for the mixture model

• Asked to place colour of target on colour wheel 

• Use mixture model to understand responses 

• Normal bell curve if normal response

• Misbinding - wrong colour = same curve wrong place 

• Guessing is just constant 

• Use distribution to understand precision 

• More items = less precision

outline attention and the resource model

Allocation of working memory resource can be biased by selective attention and towards targets of upcoming eye movements

how does the mixture model disprove the slot theory

• if slots model is true, people should be able to remember only 7 items because they only have those slots → high performance of all items until capacity where there will be no performance

• a smooth decline in precision of items is found, disproving this model

what is the dual coding hypothesis?

• concrete vs abstract nouns → concrete words are better remembered as you can imagine them and therefore have a better route to achieve them

• Piavo (1969-71): for imageable words, there are 2 routes to retrieval

what is the encoding specificity principle?

cortical reinstatement: retrieval involves the same pattern of brain activity that was present when the memory was encoded

• the way items are encoded reflects their retrieval → if conditions match, performance is improved

• retrieval cues are more effective the more similar they are to the conditions present at encoding

• aka transfer appropriate processing

outline research support for encoding specificity.

• Tulving & Thomson (1973) → paired word task

  • gave word associated with 1 word and write related words then ask if any were recognised

  • another way was to give the second word and then ask the paired word

  • better memory performance when recreated conditions in coding e.g., gave the 2nd word rather than associated

  • pair = chair + glue

  • associated word = table

declarative vs non-declarative memory

• types of LTM

• declarative/explicit memory: memory that can be consciously recalled, consisting of information that is explicitly stored & retrieved 

• nondeclarative/implicit memory: memories that cannot be consciously recalled, consisting of information that is implicitly stored and retrieved

implicit memory

• conditioning e.g., Pavlov (1927)

• priming e.g., Warrington & Weiskrantz (1968)

  • amnesiac patients

  • performed badly with the recognition procedure (explicit task) but performed normally when shown visually degraded versions of words and asked to guess (implicit task)

• skills e.g., Masters (1992)

  • concurrent task given to prevent explicit learning of golf rules

  • metronome ticking

  • every time they heard a tick they had to generate a new word to prevent coming up with strategies

  • implicit learning is more resistant to stress

episodic vs semantic memory

• episodic: memory for specific single episodes or events e.g., Tulving (2002)’s mental time travel

• semantic: stores accumulative knowledge about the world

• there is an interaction between the two

• both are types of declarative memory

outline overconfidence in the context of false memories

• Inattentional blindness 

• Failure to perceive appearance of unexpected objects in the visual environment 

• Change blindness 

• Failure to detect changes in an object 

• Change blindness blindness

• Individuals exaggerated belief that they can detect visual changes and avoid change blindness

research support for overconfidence in the context of false memories

• Levin et al. (2002)

• Aspects of the video changes

• Restaurant (different plates and wore scarves)

• Didn't detect changes even though they were warned before 

• Loussouam, Gabriel & Proust (2011)

• Easy vs difficult task 

• More likely to experience change blindness in easy tasks

• Also depends on persons belief in how good they are at the task not just actual skill

what factors can limit eye witness testimony

Confirmation bias

• Distortions of memory caused by the influence of expectations concerning what is likely to have happened

• Lindholm & Christianson (1998)

• Shown a video of a robbery

• Shown pics of 4 swedes & 4 immigrants and both were more likely to select the immigrants

• Expectation influenced as immigrants were overrepresented in crime stats

Cognitive abilities and personality

• Zhu et al. (2010)

• Individuals with better cognitive abilities resist misinformation better

• Personality characteristics like cooperativeness and avoidance have an effect on false memories (more effective on subjects with lower intelligence)

factors that may impact eye witness testimony

• Schema driven errors 

• Witnesses to crimes filter info during acquisition and recall 

• This means schematic understanding may influence how information is stored and retrieved 

• Distortion may occur without the witness realising 

• Previous and subsequent experiences 

• Assumptions 

• Stereotypes and beliefs about crime and criminals

origin of false memories

Source misattribution 

• Memory of the exact source of the information becomes confused 

Processing fluency 

• The ease with which something is processed or comes to mind

outline Gathercole’s research into school performance

• Gathercole et al (2004): WM skills linked with educational attainment

• phonological loop measures

  • digit recall

  • word list matching

• central executive measures

  • listening recall

  • backwards digit recall

• 7 year olds have a better phonological loop in all maths ability while CE is lower but increases

  • same for english but lower

• phonological loop better performance in KS3 in english, maths & science

  • CE is lower

• the intellectual operations required in maths & science are constrained by the general capacity of WM across the childhood years

• not a perfect measure though → 25% achieving normal attainment who were predicted to fall in the low attainment category based on their WM score

link with working memory and disorders and disabilities

• Swanson & Sachse-Lee (2001): math problem solving & WM in children with learning disabilities shows both executive and phonological processes are important

• Jeffries & Everatt (2004): WM has a role in dyslexia

• link between ADHD & WM → lower visuo-spatial WM capacity

training strategies

• rehearsal training e.g., articulatory rehearsal

• elaborative encoding e.g., practicing at chunking, using imagery to make items more salient, using past experience, devising a mental st

domain general vs domain specific effects

• transfer

  • pre-training measures → training → post-training measures

– Domain-General VS Domain-Specific Mechanisms

• domain specific e.g., articulatory rehearsal

  • far transfer

• domain general e.g., attention control, interference reduction, organising domain specific strategies

  • near transfer + far

outline Klingberg as research support for adaptive training

• Klingberg et al (2002): adaptive training

  • adaptive staircase procedure

  • 20 mins per day, 4-6 days a week, 5 weeks

  • training tasks were visuo-spatial training task, backwards digit span, letter span, choice reaction time task

  • control groups did not do the training, only the pre and post measures

  • one was no-contact and passive

  • other control group was ‘active’ and did a different training task

  • found that WM is not adaptive under 10mins a day

  • pre and post tests included

    • trained version of VS WM task

    • span board

    • stroop task

    • ravens progressive matrices

    • choice reaction time task

    • head movements

outline a few studies into training working memory

• Acad (2005): computerised training of WM in children with ADHD

  • parents ratings of inattention and hyperactivity or impulsivity lowered

• Holmes (2009): adaptive training leads to sustained enhancement of poor WM in children

  • 37% of pps said concentrating harder helped them improve

  • 27% said other strategies helped them improve e.g., rehearsing and tracing

• Dahlin et al (2009): transfer effects are small, or non-existent, in old age

• small effect of perceptual training on WM in older adults

• video game training enhances cognitive control in older adults

plasticity in working memory

• Scholz et al (2009): training induces changes in white-matter architecture

• increased prefrontal and parietal activity after training of working memory

• McNab et al (2009): changes in cortical dopamine D1 receptor binding associated with cognitive training

  • changes in dopamine receptor density predicted change in working memory capacity