Memory

Memory

1. Short and Long term

   • capacity
     • Jacobs: span of 9.3 items and 7.3 letters
     • Miller: immediate memory 7+/-2
   • Duration
     • STM: Peterson and Peterson- recall consonant syllables after intervals
       • artificial
       • 3 seconds= 90% 9 seconds= 20% 18 seconds= 2%
     • LTM: Bahrick- 15 yrs= 90% 48 yrs= 70%
       • Artificial: results could be due to displacement

2. Coding

   • Baddeley: STM encoded acoustically (can be visual) LTM encoded semantically (can be visual)

3. Multi-Store Model

   • Atkinson and Shiffrin
   • sensory register: small capacity supporting evidence: lab studies support separate short and long term stores
   • STM: immediate use, limited duration
     • Maintenance rehearsal: transfers information from STM to LTM
       • LTM: potentially unlimited duration and capacity
   • STRENGTHS: large base of research that supports the idea of the distinct STM and LTM systems (Patient KF) - it makes sense that LTM are encoded semantically (e.g. you might remember the general message of the speech but not every word) - pioneering model of memory and inspired further research and other influential models
     • WEAKNESSES: some reserach into the STM has low ecological validity as the stimuli the PP's were asked to remember bear little resemblance to items learned in real life (Peterson and Peterson) used nonsense trigrams 'VXG' to investigate STM duration - over simplified as evidence suggests that there are multiple STM and LTM stores

4. Working Memory Model

   • Baddeley
     • Central Executive: direct attention to tasks , how resources are allocated, limited capacity, explanation too vague
     • Phonological Loop: limited capacity, auditory information and preserves order, maintenance rehearsal, Dual task performance:task involving same process twice was slower
     • Visuospatial Sketchpad: spatial tasks and visual information, Patient KF: short term forgetting auditory info, restricted to Phonological Loop-suggests 2 stores
     • Episodic Buffer: facilitates communication between the central executive and LTM
   • STRENGTHS: Supporting evidence (Shallice and Warrington) CASE STUDY: Reported that patient KF could recall verbal but not visual info immediately after its presentation (supports the idea of separate stores) - the model was based on evidence from laboratory experiments so confounding variables could be controlled to produce reliable results
     • WEAKNESSES: the WWM has been criticised for being to simplistic and vague (its unclear what the central executive is and its exact role in attention) - Results from lab experiments have low ecological validity as tasks are artificial and not representative of every day life

5. Types of Long Term Memory

   • Episodic
     • involves the storage and retrieval of personal experiences and events (e.g. what you had for breakfast)
     • Areas active: Hippocampus, temporal lobe and frontal lobe
   • Semantic
     • involves the storage and retrieval of general knowledge and information (e.g. facts and definitions)
     • Areas active: temporal lobe
   • Procedural
     • involves the storage and retrieval of skills and habits (e.g. riding a bike)
     • Areas active: Cerebellum and motor cortex

6. Explanations for forgetting

   • Retroactive Interference: current attempts to learn something new interfere with old info
     • Proactive Interference: past learning interferes with new info
   • Interference: McGeoch and McDonald- (List 1= synonyms= least accurate (12% recall)) (List 2= antonyms) (List 3= unrelated words) (List4= nonsense syllables (26%)) (List 5= 3-digit numbers= least effect (37%)) (Control condition= no new list)
   • Retrieval Failure Theory: when the info is in the LTM but can't be accessed (available but not accessible) because the retrieval cues aren't present
     • External/Context- in the environment, e.g. smell, place
     • Internal/State- inside of us, e.g. physical, emotional, mood
     • Tulving (1974)- argued that info would be more readily available if the retrieval cues present when the info was encoded were also present when the retrieval is required
     • Baddeley (1975)- deep sea divers, memorize a list of words (same environment recalled 40% more words than those in different environment) shows importance of context
     • Goodwin (1969)- investigated the effect of alcohol on state-dependant retrieval, they found that when people encoded info when drunk, they were more likely to recall it in the same state
   • Eye Witness Testimony: Misleading info- (Loftus and Palmer)- 45 students shown traffic accidents, critical verbs: smashed, collided, bumped, hit- more violent words estimated higher speeds
     • Post Event Discussion: Gabbert (2003), sample of 60 students from uni of Aberdeen and 60 older adults from local community- 71% of witnesses in the co-witness group recalled info they hadnt seen and 60% said the girl was guilty
     • Anxiety: arousal has a negative effect on performance- weapon focus effect (Johnson and Scott) 33% recall in high anxiet and 49% recall in low anxiety
       • Pickel: claimed not due to anxiety but suprise (best accuarcy in high suprise condition), individual differences of emotional sensitivity
   • Cognitive Interview: encourages interviewee dominance- report everything, change order, change perpective