memory :)

• 3 types of memory

  • sensory register
  • short-term memory
  • long-term memory
• sensory register


  temporarily stores info from our senses

  no attention= spontaneous decay

  limited capacity and duration

  info is coded depending on what sense picked it up

  research support= Sperling 1960 into duration
• short-term memory


  limited capacity and duration [18- 30 seconds, capacity around 5-9 items]

  coding usually acoustic [sound]

  research support= Miller 1956 capacity, Peterson+Peterson 1959 duration, Jacobs 1887 capacity
• long-term memory


  unlimited capacity and 'permanent'

  coding usually semantic [meaning]

  3 types of LTM= episodic, semantic, procedural memory

  research support= Bahrick et al 1975 duration
• coding


  how information is stored

  STM- keep info active by repeating it to ourselves [acoustic encoding]

  LTM- code words in terms of their meaning [semantic encoding either visual/acoustic]
• Episodic memory [LTM]


  info about events ( events that lead to memories)

  declarative- conscious recall
• Semantic memory [LTM]


  info about facts and knowledge ( specific meaning to us)

  declarative- conscious recall

  no details on time/ where it's learnt
• Procedural memory [LTM]


  info about how to do things

  can't be consciously recalled- muscle memory
• Sperling 1960- research into sensory register duration


  lab setting shown a 3x4 grid for 1/20th of a sec

  • had to immediately recall either whole grid or row chosen by tone played outloud
  • results= whole grid was averagely 4/5 letters, row was average of 3 letters no matter the row
  • didn't know which row would be selected so they tried to recall 3 from any row- almost whole grid stored in sensory register

  +lab experiment so very scientific, controlled, replicable

  -artifical setting so lacks ecological validity, not real to life
• Miller 1956- research into STM capacity


  capacity of STM is 7+-2 ( magic number)

  suggested we use 'chunking' to combine individual numbers/ letters into meaningful units

  eg. 20031987= all digits STM can hold

  = 'chunked' 2003 and 1987 so easier to remember
• Peterson&Peterson 1959- STM into duration using trigrams


  participants shown nonsense trigrams ( 3 random consonants)

  asked to recall them after either 3,6,9,12,15,18 seconds

  during pause, asked to count backwards in 3s from a given number

  = interference task to stop repeating letters internally

  results

  • after 3secs 80% recalled of trigrams correctly
  • after 18secs only 10% were recalled correctly

  when rehearsal is prevented, very little can stay in STM for longer than around 18 seconds
• strengths of studyPeterson&Peterson


  reliable, lab experiment so highly controlled variables
• Bahrick et al 1975- duration of LTM

  • 392 participants asked to list names of ex classmates=free recall test
  • shown photos and asked to recall names of ppl shown= photo-recognition test
  • given names and asked to match them to photo= name-recognition test
  • after 15 years leaving school= recognised 90% names and faces
  • 60% were accurate on recall
  • after 30 years free recall dropped to 30% accuracy
  • after 48 years name recognition was 80% accurate, photo was 40% accurate
  • evidence for LTM in real life setting
  • recognition is better than recall so may be large info store, just harder to access
• 2 memory models


  Multi-store model- Alkinson and Shiffin 1968

  Working memory model- Baddeley& Hitch 1974
• Multi-store model 1968Alksinson and Shiffren


  The sensory register is the first store where information is temporarily stored from being detected by our sense organs before entering. here duration and capacity are limited(SPERLING)

  If information is given attention then it travels along to the STM where it has limited capacity ( Miller’s 7+-2 and Jacobs) Duration of up to 30 seconds (Peterson& Peterson)

  Information that is then rehearsed can then reach the LTM where unlimited capacity and duration with evidence of duration carried out by Bahrick. No rehearsal can still lead to forgetting.
• MSM evaluation strengths

  Idiographic case provides research support. CLIVE WEARING acquired severe amnesia. He was only able to remember up to 20-30 seconds but could however recall memories from his past, like his wife’s name. this shows he’s unable to transfer information from his STM to his LTM but can retrieve some already stored information. This supports the idea that memories are formed by passing information from one store to the other, in a linear fashion.
• MSM evaluation strengths looking at support for capacity and duration

  Miller 1959= limited capacity of 7+-2 chunks of information in the STM. Peterson & Peterson 1959= limited duration in STM of around 30 seconds. Bahrick 1975 = unlimited duration in the LTM. Studies provide evidence for different parts of the MSM and therefore suggest the model is an accurate representation of memory. However, these research support show of reductionist outlook. They explain a complex behaviour by relying on isolated variables and lab experiments to look further at capacity and duration of short term memory.
• Evidence more than 1 STM store KF


  KF has amnesia, STM recall for digits was poor when he heard them but much better when he read them

  therefore MSM is wrong to claim theres just one stm store processing different types of information
• evidence more than 1 LTM store CLIVE WEARING

  had difficulty recalling events that had happened to them in pasts (episodic) but semantic memories were unaffected ( wife's name) and procedural memories still intact ( still played piano)

  supports view that there are different memory stores in LTM because one store can be damaged but other stores still unaffected
• Working Memory model Baddeley& Hitch 1974


  not a single store for STM but multiple

  • central executive
  • phonological loop
  • visuospatial sketchpad
  • episodic buffer

  long term memory