Memory

Memory

1. Multi-Store Model

   • Atkinson & Shiffrin (1968)
   • Assumptions
     • S/LTM are separate stores
     • Info moves through sequentially
     • 1 store for each aspect of memory
   • Support for MSM
     • Serial position effect
       • Remembering the beginning and end of a list better the middle
         • Words at beginning rehearsed (LTM), end goes into STM, middle words displaced
     • KF
       • Motorcycle accident
       • No LTM problems, however digit span of STM became 2.
         • Suggests different parts of the brain are involved with types of memory
       • L/STM are separate stores
       • Forgetting of auditory info greater than visual
         • Could remember meaningful sounds but not words
     • Clive Wearing
       • L/STM stored seperately
       • Can't recall or form memories, think towards future, STM problems
       • Can read, write, has emotion, loves wife
   • Criticisms
     • HM
       • Severe epilepsy
       • Doesn't follow sequence, shows different aspects of each memory store
         • Motor learning must be distinct from system of memory that records facts, figures, faces etc
       • Remembered childhood but not more recent events, unconsciously learnt new motor skills

2. LTM

   • Duration
     • Bahrick et al (1975)
       • 392 American high school students, tested on free recall of former classmates' names and recognition of their faces
       • 15 years after leaving school; 90% correct facial recognition, 60% name recall
       • 48 years after; 70% facial recog. & 30% names
     • Potentially forever, especially with cues
   • Encoding
     • Baddeley (1966)
     • Semantic
   • Capacity
     • Untestable/unlimited - assumed
   • Types of LTM
     • Tulving et al
     • Episodic
       • 'Episodes' in our lives, time stamped, conscious recall
       • Events
         • eg, getting exam results, learning to drive
     • Semantic
       • 'Meaning' or knowledge of the world, conscious recall, not time stamped, stuff we know
       • eg, what horses/exams are like
     • Procedural
       • 'Procedures' or using skills, unconscious recall, actions/how to do things
       • eg, skipping, driving

3. STM

   • Duration
     • Peterson & Peterson (1959)
       • 'Peterson-Brown technique'
         • Trigrams, ppts recalled after delays of 3, 6, 9, 12 etc seconds.Counted back from random 3 digit number in 3's between presentation and recall to prevent rehearsal
       • Rapid increase in forgetting as time increased
         • After 3s, 80% recalled correctly; after 12s, 25%; after 18s, 10%
       • Info from STM lost rapidly with little or no opportunity to rehearse
       • Evaluation
         • Ppts could memorise counting back in 3s, then focussing more on the trigram
         • Repeated measures design, ppts could improve skills memorising trigrams
     • 18-30 seconds
   • Capacity
     • 7+/-2 items
     • Miller (1956)
       • 'Magic number 7'
   • Encoding
     • Baddeley (1966)
       • Presented ppts with 4 sets of words to recall, acoustically/semantically (dis)similar words
         • Split into two groups, immediate recall and recall after interval
       • Evaluation
         • Scientific, replicable, high internal validity
           • However it lacks ecological validity as it's a lab experiment
         • Research support - Conrad
         • Practical applications
           • Attach meaning to info to increase chance it's processed in LTM
           • Oversimplistic to assume all LTM info is semantic eg senses or visual forms
     • Acoustic

4. Working Memory Model

   • Baddeley & Hitch (1974)
   • Central executive
     • Site of conscious thought, planning & decision making
     • Attends to info
   • Visuospatial sketchpad
     • Storage of visual spatial info
     • 'inner eye'
   • Phonological loop
     • Storage of writing and language
     • 'inner voice/ear'
     • Phonological store & articulatory control process
   • Episodic buffer
     • Integrates info
     • Just an assumption
     • Brings in info from LTM
   • Evaluation
     • Some aspects lack clarity (episodic buffer)
     • Appreciates complexity of human memory
     • Some supporting evidence from brain research

5. Forgetting

   • Interference
     • Proactive
       • Older memories disrupt newer ones
     • Retroactive
       • New memories disrupt old ones
     • Worse when memories are similar
       • John McGeoch & William McDonald (1931)
         • Studied retroactive interference by changing amount of similarity between 2 stimuli. Ppts had to 100% memorise a list of words
           • Learned new list of words after
             • Synonyms, antonyms, unrelated, nonsense syllables, 3 digit numbers & no list
         • Most similar material produced worst recall (group 1)
         • Evaluation
           • Lab experiment
             • High external validity
             • High control
             • Greater chance of interference in lab setting
   • Retrieval Failure
     • Insufficient cues
     • Encoding specificity principle
       • Tulving (1983)
       • We can recall well with a cue at encoding and at retreival
       • Should be the same cues to avoid forgetting
   • Context-dependent forgetting
     • Deep sea divers
     • Remember list of words with 4 conditions
       • Learn on land recall on land/water
       • Learn on water recall on land/water
     • Accurate recall 40% lower in non-matched conditions, different external cues led to retrieval failure
   • State-dependent forgetting
     • Anti-histamine drugs with drowsy effect given to ppts creating internal different psychological state

6. Eye Witness Testimony

   • Leading questions
     • Loftus & Palmer (1974)
       • Ppts watched film clips of car accidents and were asked how fast the cars were going. Used different leading questions for different groups who watched the same video
         • Contacted, bumped, hit, collided, smashed
         • 'Contacted' mean estimate - 31.8mph; 'smashed' mean estimate - 40.8mph
       • Evaluation
         • Artificial stimuli, standardised, replicable
         • High internal validity, controlled
           • Low external, video
         • Could trigger car crash victims
         • Practical apps in police questioning
   • Yerkes-Dodson Law (1995)
     • Normal distribution on anxiety affecting recall
     • Performance is best in moderately arousing conditions
     • Johnson & Scott (1976)
       • Anxiety has -ve effect on recall
       • Ppts believed they were taking part in lab experiment, heard argument in other room
         • 'Low-anxiety' cond. - man walked out with pen
           • 'High-anxiety' cond. - man walked out with bloody knif
       • Ppts picked man from set of 50 photos, 49% of low anxiety cond. correctly identified man. 33% in high anxiety group
         • Tunnel theory of memory - witness' attention narrows to focus on weapon; source of anxiety
           • Weapon focus effect
       • Evaluation
         • Methodology
           • Not scientific
           • No variation in conditions, extreme incr. in violence
           • Replicable, standardised
         • High internal/external validity
         • Not 100% informed consent, risk of psychological harm
         • Useful for police
     • Yuille & Cutshall (1986)
       • Anxiety has +ve effect on recall
       • Real-life shooting in gun shop, owner shot thief dead. 21 witnesses, 13 took part
         • 4-5 months after, interviews were conducted & compared to police interviews made straight after incident
           • Rate stress /7
       • Ppts with higher levels of stress recalled more accurately (88% compared to 75%)
   • Post-event discussion
     • Fiona Gabbert et al (2003)
       • Studied ppts in pairs, each watched video of the same crime, filmed from different points of view
         • Discussed what they saw before recall
       • 71% ppts mistakenly recalled aspects they hadn't seen but picked up in discussion. Control group with no discussion was 0%.
         • Phenomenon memory conformity
   • Cognitive Interview
     • Fisher & Geiselman (1992)
     • Techniques
       • Context reinstatement
       • Change the perspective
       • Reverse the order
       • Report everything
     • Valentine & Mesout (2009)
       • Labyrinth of Horror
       • Ppts completed questionnaires after experience & wore heart monitors to confirm anxiety was being experienced. Two groups; low/high anxiety
       • Describe person encountered (actor), high anxiety group recalled fewest details
         • High anxiety - 17% correctly recalled, low anxiety - 75%
       • Evaluation
         • Scientific, standardised, replicable
         • High external, low internal validty
         • Informed consent
     • Geiselman et al (1985)
       • Ppts watched film of violent crime & were interviewed 48h later using, cognitive interview, standard LA police interview or interview using hypnosis
       • Average number of correctly recalled facts was recorded
         • Cog. interview - 41.2; standard - 38.0; hypnosis - 29.4
           • Cognitive interview leads to better recall of events
   • Weapon focus effect
     • Loftus et al (1987)
       • Slides depicting event in fast-food restaurant. Half of ppts saw man point gun at cashier, other saw someone hand cashier cheque. Eye movements recorded
       • Ppts focussed more on weapon, fixations on weapon longer. Memory for person holding te gun worse thsn for cheque.
       • Support for weapon focus effect
       • Evaluation
         • Scientific, objective, standardised, replicable
         • High internal/external validity
         • Ethics, psychological harm
         • Useful