Cognitive Psychology

Multi-Store Model (Atkinson & Shiffrin 1968) LINEAR STM & LTM

Episodic & Semantic Memory Theory (Tulving 1972, 1985 procedural) LTM NOT UNITARY

Reconstructive Memory (Bartlett 1932) SCHEMA FOR STM & LTM

Working Memory Model (Baddeley & Hitch 1974, Baddeley 2000 ep. buffer) STM NOT UNITARY

HM Henry Molaison: hit by bicycle as a child, giving him severe epilepsy, experimental brain surgery at age 27, had hippocampus and surrounding tissues removed from medial temporal lobe. Experiences retrograde amnesia from age 16 due to surgery, where no new LTMs can be formed, but still intact STM and normal IQ.>

Hippocampus does not store LTMs as old intact, hippocampus is responsible for transfer of information from STM to LTM and hippocampus deals with episodic LTM, but not procedural LTM as shown with mirror-star-drawing task (Milner 1962) & Tower of Hanoi (Corkin 1981)

Clive Wearing: musician developed viral encephalitis afffecting hippocampus. Intact old LTMs (playing piano, reading music, wife's face), & intact STM, but no new LTMs formed, so constant belief he has awoken from a coma.

KF (Shallice & Wallington): intact LTM, but not STM, so memory is not a linear process

KC:

Phineas Gage (1848): iron rod went through frontal lobe, no impairment just personality shift (disrespectful, rude, irresponsible)

Schmolck et al 2002: case study of 14 brain-damaged patients found temporal lobe deals with semantic memory, & medial temporal lobe deals with episodic memory, suggesting  different types of LTM encoded in different parts of brain

• -Not generalisable to everyday healthy population as only 1 uniqe ppt where memroy is affected in very specific way   
• +can replicate on same brain-damage patient to retest for reliability, as studies use standardised procedures such as brain scans & memory tests such as Tower of Hanoi (Corkin 1981)  -can only retest on same ppt, so hard to replicate  +Inter-ratum data collected strengthening reliability of case studies, as interviews, brain scans, memory tasks, questionnaires all give similar findings (e.g HM procedural LTM but not episodic)      +Reliability good as quant. data from brain scans & timed memory tasks (e.g mirror-drawing task Milner 1962), so compared to control group    -some qualit. data from interviews, questio., observ. where exp. bias affects results
• +Good application as can learn functions of brain parts (e.g hippocampus frming new LTMs HM/Clive Wearing) which is useful when understanding memory effects of brain damage  -not applicable to healthy pop., only helpful for small %
• +Validity as scientific studies in hospitals, so control over variables like food & light which may affect memory, allowing C&E relationship to be established between brain damage & memory loss, so can compare to healthy control group
• +Ethically okay compared to intrusive techniques where damage must be made, such as explora. surgery, brain lesions, implanted elctrodes,   -unethical to study brain damage patients who cannot give informed consent, due to bad STM
• Conclusion: good for understanding functions of brain parts & reliable with inter-ratum data, however issue of generaliability affecting real-life application to healthy  population & no consent, usefulness limited to small % of pop.

Atkinson & Shiffrin 1968

Sensory register: 5 senses, storage duration upto 3 seconds, storage capacity upto 4 items

Short-term memory: mostly auditory, duration upto 30 seconds, capacity 5-9 items

Long-term memory: visual/auditory/semantic, duration lifetime, capacity limitless

Attention must be paid to information for it to pass into STM, or it decays.

Must Rehearse information for it pass into LTM, or it decays.

Must use rehearsal loop to retrieve information from LTM, into STM, or it decays over time.

Modality specific (stored in same mode as it was sensed)

Diff. stores: +Clive Wearing (encephaltis) & HM (hippocampus removed due to seizures) intact STM/old LTMs, but can't transfer info. from STM to LTM, preventing new LTMs  -not generalisable to ordinary population as unique case studies  

 STM has capacity of 7+/-2: +Glanzar & Kunitz 1966 (primary-recency effect due to word list, as STM can only hold last 5-9 words in list)   -bad task validity, as not representative of real life memory tasks   STM has duration of upto 30 seconds: +Peterson & Peterson 1959 (only 10% of trigrams remembered after 18 seconds as information passed to LTM)   -bad task validity, as not representative of real life memory tasks

LTMs decay if no rehearsal: +Brown & McNeill 1966 (tip-of-the-tongue phen. only partial copies of memory traces retrieved)     Rehearsal loop is used to retrieve information: Peterson & Peterson 1959 (only 10% of trigrams remembered after 18 seconds of not rehearsing)

-Not linear process KF case study (Shallice & Wallington 1970) had intact LTM but not STM, & could still form new LTMs

-MSM too simple: Episodic&semantic memory (Tulving) different types of LTM not in MSM, WMM (Baddeley&Hitch 1974) diff. types of STM & encoding/storage not linear process -contradicts/weakens Multi-store 

Conclusion: +Application understand brain damage effects e.g HM hippocampus, & to learning techniques e.g chunking 5-9 items STM, role of rehearsal. -Either bad task validity with sup. studies or not gen. as unique case studies. Too simple shown by KF case study & WMM & E/S theory

Tulving 1972 theory for different types of long-term memory

Episodic: personal experiences encoded chronologically, stored alongside spatial location & temporal relation (where/when), retrieved in chronological order using cues (memory chain), prone to inaccuracies & reconstructive errors

Semantic: facts/knowledge, encoded in no order, stored alongside words/rules/meanings/concepts, retrieved in any order according to words/rules/meanings/concepts, but not using cues

LTM not unitary: +case study of KC (bad epi. LTM, good semantic LTM so in diff. parts of brain, +case studies HM/Clive Wearing (bad episodic LTM as couldn't remember practising drawing star in mirror or Tower of Hanoy, good procedural LTM (Tulving added to theory in 1985) as improved at tasks)   -not generalisable to everyday person as unique, brain-damaged cases with 1 ppt.

Cue-dependent recall of episodic: +Godden & Baddeley 1975 (scuba divers learn word lists water or land, better recall in same environment, spatial location is cue for recall)  -Low task/ecological validity as not real-life task or setting for memory task, +Ucros 1989 (40 studies of mood-state-dependent episodic recall)  -but not as sig. for matched negative moods

-MSM Atkinson & Shiffrin 1968: E/S theory only covers LTM, whereas MSM covers both STM & LTM, E/S doesn't explain how/why memories are made whereas MSM does (attention/rehearsal)

-WMM Baddeley & Hitch 1974: E/S theory dismisses STM unlike WMM which covers it in detail (central ex, visuo-spatial sp, phon.loop, epi. buffer), so E/S too simple

Conclusion: useful application: +learning techniques (recall in learning enviro. for cues), understanding brain-damage (HM/Clive Wearing different types of LTM)  -lacks science as E/S not situated in brain, -STM not covered so too simple  -either bad gen. or bad task validity

Bartlett 1932

• Memory is not like a video recorder because:
• Gaps in our memory recall are reconstructed with our expectations, which are based on our schema
• Schema are pockets of knowledge from previous experiences of events, places, people...

• Bartlett based his theory on his own War of the Ghosts study in 1932 which aimed to find out if memory is affected by previous knowledge
• 20 people told unfamiliar native-American fable through serial reproduction
• Had to reproduce in intervals (from 15 minutes to 10 years)
• Shortened story, rationalised parts to make relevant to them, confabulated parts (made up)
• Therefore memory is inaccruate, as it is reconstructed based on personal schema

Memory is inaccurate: +Allport & Postman 1945 (audio description of scene through serial reproduction, accuracy decreases, shortens & confabulation)   -bad task validity as not representative of real-life memory task

Gaps reconsructed using schema (pockets of information gained from previous experiences): +Allport & Postman 1947 (image of white man holding knife at black man recalled other way, as black knife-crime schema)   +Vincente & Brewer 1993 (students studied research paper with some mistakes, read correct version, still recalled incorrect as schema of well-known published study)  +task validity as real-life scenarios

+War of ghosts study Bartlett 1932 (serial repro. of fable, confabulation, shortened, inaccuracies)    -no specific regular intervals, so bad retest reliability   -aim could be guessed so demand characteristics (try more/less for experimenter's expectations) reducing validity   -bad task validity as artificial, irrelevant task of remembering text, leading to more reconstructive errors being made (Steyvers & Hemmer)

-Another theory is that scheme influence memory recall as early as encoding the memories    -doesn't explain how memories are recalled (through rehearsal (MSM) or where in brain (WMM)) so lacking in detail    -no individual differences in memory recall (depression, dyslexia) when WMM does

Conclusion: +application explain/prevent reconstructive errors in eyewitness test. (gun schema in bank robbery), task validity of supporting studies (A&P 1947/V&B 1993), but bad task validity (S&H) & demand characteristics for Bartlett 1932 which led to theory creation, which fundamentally weakens RCMT

Baddeley 1966b experiment 3- accoustic & semantic similarity on LTM for word sequences

Baddleey 1966a found that STM stores mainly accoustic memories

Aims: Are LTMs stored mainly accoustically or semantically? Are STMs & LTMs stored differently?

Procedure: 4 word lists, 4 groups, see 3 seconds each word, filler task, recall words, filler task, recall words (retest)

Findings: Accoustically similar/dissimilar words showed little memory difference, but semantically dissimilar words are easier to remember than semantically similar words especially on the retest (trial 4) which shows definitely LTM

Conclusion: STM stores mainly accoustically & LTM stores mainly semantically, therefore STM & LTM must use different parts of the brain for storage

+generalisable as both males & females in sample  -small sample size (21 in each condition) , weakening generalisability

+the study can be replicated to retest for reliability because it used standardised procedures like specific word lists, exact timings like 15 minute filler task before retest

+quantitative data collected (number of words correctly recalled) so reliable as objective (no ex. bias)

+good application as contributed to further memory research e.g WMM Baddeley & Hitch 1974, which has led to understanding of how dyslxia affects learning & help (diagnosis testing, teaching techniques to help, software like Cogmed to train WM)

+good internal validity as in lab setting, so control over ex. variables like light/noise (which may be distractions in memory tasks, affecting results), to establish C&E relationship between similarity of words in list & memory recall  -but bad task/ecological validity as artificial lab setting/task so unnatural memory recall

-bad validity as participant variables from independent groups design so cannot compare results as every person has unique memory capacity under each condition (m.pairs or rep. measures would be better)

Conclusion: led to WMM, so it has had useful repercussions which have had good application (dyslexia), is reliable as can easily be replicated, but using indep. groups design is problematic as weakens validity. 

Baddeley & Hitch 1974 (STM)

Assumptions: STM is not unitary, LTM is passive and is used by STM when necessary

'Phonological loop': phonological store (inner ear) stores audio for 1-2 seconds, articulatory loop (inner voice) rehearses audio

'Visuo-sptial sketchpad': (inner eye) visual & spatial memory

'Central executive': (manager) focus attention, divide attention, switch between tasks, retrieve in from LTM

'Episodic buffer': added by Baddeley 2000, sorts chronological order of events & integrates with central executive

• STM is not unitary (auditary, visual): +KF (Shallice & Wallington) good visual (vs sketchpad) but bad auditory (phon. loop)   -not gen. as unique 1 ppt, +Klaeur & Zhao 2004 dual diff. tasks easier than dual sim. tasks  -bad task validity
• Phonological loop (ph store & art. loop audio) +Smith & Jonides 1997 brain scans, auditory=left hemisphere
• Pho loop time limit of 2 secs: +Word-length-effect Baddeley 2003 long words (2 secs to read) harder to remember
• Visuo-spatial sketchpad: +Smith & Jonides 1997 brain scans, spatial=right hemisphere
  
• managing role of central executive: +Baddeley & Hitch 1976 dual tasks of counting & reasoning task very few errors   -bad task validity as artifical not real life WMM tasks
• good application as helped with understanding of dyslexia affecting learning (WM), struggle with phonological/spatial awareness, so diagnosis testing (DEST-2), can train WM online (Cogmed), adapt learning techniques, extra exam time
• -does not fully explain role of central executive (just attention, manages other parts of WM)
• -dismisses LTM as passive, so incomplete explanation, HM had no new LTMs which greatly affected him, so LTM is important & must be addressed. Tulving deals with LTM in episodic/semantic theory 1972> too simple, need overarching, detailed theory
• Conclusion: very useul (dyslexia), detailed explanation of STM with consitency between firesearch giving reliability, however dismisses LTM as passive. Needs LTM to be expanded to be full explanation of memory

• Mostly developmental (rather than acquired from brain damage) so:
• genetic (chromosones 3, 6, 15,) 1/2-2/3 likely to have if parents have it
• genotype expressed at reading age 5, english language complex so more dyslexia in England

Impacts:

• Cognitive (intelligence unaffected): affects WM which affects learning ability
• Ramus et al 2003 studied 16 dyslexic people & found 16/16 phonological awareness deficits (rearranging sounds, reading, allliteration), 10/16 auditory deficits (letter-sound conversion), 4/16 motor defecits (handwritin), 2/16 visual defecits (visual fixation, keeping eyes focused

How to help:

• diagnosis testing (DEST-2)
• Use online WM training continuously (Cogmed)
• adapt teaching techniques (break up taks, re-present info., use memory aids, encourage child to ask for help to remember task)

Is eyewitness testimoney reliable?

• What is eyewitness testimony? Eyewtinesses of crimes recall what they saw/heard at crime scene to the police, which is then used as evidence in court
• It is important to understand why eyewitness testimony is unreliable because it can have impacts on individuals & society:

Direct impacts on individuals: innocent person may be prosecuted so they may go to prison or face other charges, which will affect their family life, job income and life as a whole. Guilty person is still free, so they can continue to commit crimes & endanger those around them

Indirect impacts on society: As crimes of guilty person may continue, the police wil face sosts to prevent this crime from happening, & court costs to retrial innocent person and prosecute guilty person, compensation pay-outs to convicted innocent person, all money comes from taxes, which reduces money spent on other causes such as other police work, education & healthcare,& taxes paid by everyday people so whole of society affected

Example: Ronald Cotten was wrongly convicted of ****, 2 counts of burglary & was sentenced to life imprisonment +54 years, due to the victim's misidentification of the guilty man. Cotten spent 11 years in prison , lost a decade of his life which affected his family relationships, lost his job & finances. Appealed in 1995 & had his semen tested for a match. Police had to pay for retrial & compensation

Is eyewitness testimony reliable? How do the theories I've learned about show eyewitness testimony to be unreliable?

• Reconstructive memory theory (Bartlett 1932):  People fill in memory gaps with schema (expectations based on past exps.), so reconstructed memories are inaccurate. When applied to EWT, assumes EWs make reconstructive errors when recalling details of a crime scene due to schema e.g EW of a bank robbery may falsely recall a gun in burglar's hand, as films/TV depict a gun in such scenes, leading them to have this schema, making EWT unreliable
• Multi-store Model (Atkinson & Shiffrin 1968): People must pay attention to sensory info, to encode STMs, then rehearse to encode LTMs or it will decay. When applied to EWT, assumes EWs may not remember details of crime scene as not paying attention to crime (safety, distractions) also no time to rehearse to encode LTMs, so will form inaccurate memories, making EWT unreliable e.g pay attention to gun type not attacker's features to identify
• Working Memory Model (Baddeley & Hitch 1974): People's WMs differ greatly due to complexity of WM> STM not unitary as phono. loop (auditary inner ear/voice), visuo-spat. sp (inner eye), managed by central ex, epi buffer (chrono. events). When applied to EWT, assumes EWs may recall crime scene diff. e.g low-functioning epi. buffer remember diff. event order in fight so man defending himself is prosecuted, dyslexic people low-func. phono. loop may not remember auditoary details accurately, therefore EWT is unreliable
• Misinformation Effect (Loftus et al 1978): Post-event info. contaminates original memory. When applied to EWT, assumes EW memories are inaccurate due to leading qu's from investigators, discussion with other EWs, inaccruate media reports, therefore EWT is unreliable

Sebastian & Hernandez-Gil 2012 digit span in Spanish population

• Digit Span Test Sebastian & Hernandez-Gil 2012
• Background: Gathercole et al 2008 found English people's digit span increases with age & peaks at age 15
• Aims: Will Spanish people's digit span peak at age 15 as well? Do age & neurodegenerative diseas such as Alzeheimers affect digit span?
• Procedure: volunteer sampling of 570 native school children from Madrid with no impairments, aged 5-17 years old split into 5 age groups, volunteer sampling of 59 elderly people (25 with dementia, 25 with Alzeheimers, 9 controol healthy ppts). hear increasingly long sequences of numbers at rate of 1 per second, individually recall numbers chronologically, their digit span is max. number of numbers recalled for 2/3 sets

Results:

• in Spain digit span peaks at age 17=average 5.83, average aged 5=3.76
• no sig. difference between healthy ederly & elderly with neurodegenerative diseases
• after peak age 17, digit span decreases, elderly average digit span=4.34 (7-9 yr old)

Conclusion: phonological loop (auditory info.) improves, peaks at age 17, decreases so at age 70 average of 7-9 year old. Alzeheimers/dementia do not affect functioning of phonological loop

+Generalisable to large % of Spanish population: children as large sample size of 570 ppts, & to elderly as 59 ppts (including neurogenerative elderly)   -sample is ethno-centric as only Spanish citizens, so not generalisable to other countries, particularly non-Western cultures  -volunteer sampling therefore may only repreent conscientious, generous, extroverted people so not generalisable to others

+Reliable as consistency between findings using same digit span test: Gathercole & Alloway 2008 England peaks at age 15, Engle & Marshall 1983 5-6 year olds digit span of 4

+Reliable as standardised procedures such as 1 second per digit, increasing by 1 digit per sequence, so can easily be replicated to retest for reliability

+Good application as digit span test can be used as part of dysleixa diagnosis as early as age 5 as it evaluates effectiveness of phonological loop, which is part of WMM

+Good internal validity as ppts tested individually & shown digit span test before beginning to prevent misunderstandings or ppts variables disrupting C&E relationship of age & digit span    -bad task validity as artificial task not like real life memory tasks which often semantic meaning (e.g phone number) leading to unnatural behaviour

Conclusion: highly generalisable to Spain & Western countries, but lacking in generlisability for non-western countries. Very reliable due to consistecy in findings & easiness to replicate to retest. Bad task validity as not reflective of real-life semantic memory tasks, however it ha good applications such as dyslexia diagnosis, which show how important this study has been, therefore overriding bad task validity

Aim: Diff. in memory recall between rehearsal-allowed & rehearsal-prevented ppts. Retesting Peterson & Peterson 1959 only 10% items in STM remembered after 18 seconds & all lost at 28 seconds. Atkinson & Shiffrin 1968 MSM assumes rehearsal needed to encode LTM. independent groups design (rehearsal allowed/prevented) recall list of 20 trigrams.

IV/DV: operationalised IV= 'rehearsal-allowed or rehearsal-prevented', DV operationalised= 'number of trigrams correctly remembered out of 20'

Hypotheses: experimental='Rehearsal-allowed ppts will have better memory recall (number of correctly remembered trigrams out of 20) than rehearsal-prevented ppts'. null='there will be no difference in memory recall (number of correctly remembered trigrams out of 20) between rehearsal-allowed & rehearsal-prevented ppts. Any difference will be due to chance.'

Procedure: 1) wrote 20 trigram list, no acronyms. Pilot study (1 min whiteboard, 1 min recall>use paper copies to prevent cheating). apparatus =10 copies of trigrams, stopwatch, paper/pens, Opportunity sampling to gather 10 16-19 year old Abbey College students from corridors during lunch time. 2) Ethics= informed consent & written brief, right to withdraw, debrief  3) First 5 ppts, 1 min to memorise 20 trigrams from sheet, took trigrams away after 1 min, 1 min to recall trigrams on paper, debrief, left. Next 5 ppts, 1 min to memorise trigrams on sheet, took away trigrams, 1 min filler task of rhyming with 'sky', 1 min recall, debrief, left. Tallied number of trigrams correctly remembered out of 20, put in results table. Measures of central tendency, range & standard deviation calcuated. Histogram for rehearsal-allowed ppts/ scores. Mann Whitney U Test as difference in memroy recall, independent groups (1 group under each condition), collecting interval/ratio data (equal intervals between scores out of 20)

rehearsal-allowed mean: 4.8    rehearsal-prevented mean: 4

rehearsal-allowed SD: 1.3        rehearsal-prevented SD: 2.1

bigger spread of scores for rehearsal-prevented, but no sig. diff.

Mann Whitney U Test: one-tailed, 5%, observed value=9.5, critical value=4

No significant difference in memory recall (number of trigrams correctly remembered out of 20) between rehearsal-allowed & rehearsal-prevented ppts, therefore we can accept the null hypothesis & reject the experimental hypothesis, which contradicts Pterson & Peterson/s 1959 study which found sig. diff & Atkinson & Shiffrin's 1968 MSM theory that rehearsal is required to form new LTMs. Therefore, I conclude that in this study, rehearsal did not have a significant impact on the effectiveness of memory recall.

Strength: Our study's findings are reliable because we used standrdised procedures t=such as specific & exact 1 minute timings using a stopwatch for the memorising stage, filler task stage & recall stage, & we used the exact same list of trigrams throughout the study, meaning the study could eaisly be replicated to retest for reliability.

Weakness: Reliability is weakened because previous research such as Peterson & Peterson 1959 who found that rehearsal improves memory recall significantly, and Atkinson & Shiffrin's 1968 MSM theory, contradict our findings that rehearsal made no signficant difference to memory recall (trigrams correctly remembered out of 20). This incongruency suggests our study is unreliable.

Improvement: Our conclusion that rehearsal does not affect memory recall contradicts prevous research, making our study unreliable. Perhpas our findgins are inaccurate because our target population of 16-19 year old Manchester College students, is too narrow. Age could be a confounding variable, because maybe at a young age memory recall is unaffected by rehearsa. If I was to conduct this study again, I would use the same procedures, but sample all different ages (from 10-70 years old), so that the study's findings would be generalisable to a wider target population of British people all ages and there would be a wider difference in memory recall between rehersal-allowed & rehearsal-prevented participants.