AQA A Level Psychology - Memory - Paper 1

• define memory

  The process by which we retain information about events that has happened in the past
• define coding

  format in which information is stored in various memory stores
• define duration

  length of time info held in memory
• define capacity

  The amount of information that can be held in a memory store
• what is the capacity of the sensory register?

  unknown but very large
• What is the duration of the sensory register?

  very limited, 250ms
• What is the coding of the sensory register?

  raw unprocessed information from all 5 senses
• What is the capacity of STM?

  limited, 7+/- 2 chunks
• What is the duration of STM?

  limited, 18-30s (P&P)
• What is the coding of the STM

  acoustic
• What is the capacity of the LTM

  unlimited
• What is the duration of the LTM

  lifetime
• What is the coding of the LTM

  semantic
• Who investigated the capacity of STM

  Miller (1956)
• describe Miller's study

  aim - investigate capacity of STM

  method - reviewed published investigations into perception and STM

  results - STM could cope with about 7 +/- 2 pieces of information

  conclusion - organisation of info can extend capacity of STM
• What are the strengths of Miller's study?

  - research support, Jacobs conducted digit span test finding people could remember 7.3 letters and 9.3 numbers
• What are the weaknesses of Miller's study?

  - not precise, didn't specify how large each chunk could be so cant conclude exact capacity, further research required

  - didn't account for other factors, Jacobs found that Age increases STM capacity
• Who investigated the duration of STM

  Peterson and Peterson (1959)
• Describe Peterson & Peterson (1959)

  Aim - investigate duration of STM in lab experiment with 24 students

  Procedure - recall meaningless trigrams. To prevent rehearsal, students count backwards in 3s/4s from random numbers, then recall

  Findings - longer interval = less accurate recall. At 3 seconds 80% remembered, 18 seconds 10% remembered

  Conclusions - STM has limited duration of about 18 seconds. No rehearsal = not passed to LTM, supporting the MSM
• What are the strengths of Peterson & Peterson

  - lab study, highly controlled and therefore has high validity
• What are the weaknesses of Peterson & Peterson

  - poor sample - used only American uni students, may have encountered MSM before or had different memory to non-uni students. cant generalise

  - task lacks mundane realism, unlike tasks used for memory in everyday life
• Who investigated the duration of LTM

  Bahrick et al (1975)
• Describe Bahrick's study

  aim - to investigate the duration of LTM

  method - 392 American high-school graduates shown photos from yearbook and mad to match names to photos

  results - 14 yrs = 90% accurate, 47 years = 60% accurate

  conclusions - LTM has a very long duration, up to a lifetime
• What are the strengths of Bahrick's study?

  - task has ecological validity, recognising faces is a real-life memory compared to the artificial tasks used in other studies
• What are the weaknesses of Bahrick's study?

  - lacks population validity, American students to unable to generalise to whole target pop

  - not full explanation, LTM did decrease with age, therefore is LTM actually unlimited or is it affected by age?
• who investigated the coding of STM and LTM

  Baddeley
• describe Baddeley's coding study

  Method - pps were shown a list of words, then asked to recall them in the same order either immediately, or after 20 mins. Group 1 - acoustically similar words, group 2 - acoustically dissimilar words, group 3 - semantically similar, group 4 - semantically dissimilar

  Findings - pps did worse with acoustically similar words immediately, and worse with semantically similar words after 20 mins

  Conclusions - suggesting that info in STM is coded acoustically, as the similar sounding words conflicted in STM. Suggested that LTM is coded semantically, as info with similar meaning conflicted in the LTM.
• What are the strengths of Baddeley's coding study?

  evidence for different in STM and LTM memory stores. Helped lead to MSM
• What are the weaknesses of Baddeley's coding study?

  artificial stimuli - word lists have no personal meaning to participants, and therefore this research may not tell us much about coding in types of everyday memory tasks. Therefore, it has little real life application.
• What are the strengths of the MSM?

  - support from case studies, HM lost STM but retained procedural LTMs after hippocampus removal, supports separate stores of memory

  - support from lab studies, peterson & peterson, miller, Bahrick.

  - objective and scientific research from brains cans show different areas of the brain active during retrieval of STMs and LTMs
• What are the weaknesses of the MSM?

  - criticism from WMM. splits STM into phonological loop and visuo-spatial sketchpad. therefore it lacks complexity and detail included in WMM

  - reductionist, memory too complex for singular model. ignores work of WMM, or effect of emotion on memory ect.
• What are the 3 types of LTM?

  episodic, semantic, procedural
• what are explicit memories?

  knowledge for events and facts. can easily be articulated into words.
• What are implicit memories?

  skilled behaviours that are largely unconscious. hard to articulate in words
• What are episodic memories?

  memories of personal experiences and life events
• Are episodic memories explicit or implicit?

  explicit (declarative)
• What is the strength of episodic memories determined by?

  strength of emotion experienced at the time
• Are Episodic memories time stamped?

  yes
• What area of the brain is episodic memories associated with?


  hippocampus
• What are semantic memories?

  memory for knowledge of the world, including fact, concepts and meaning of the world around us