memory

• Strength of the MSM


  Research support For example the case of HM, because HM suffered severe memory loss however, although his short term memory was normal, he was unable to ever transfer new information to long term memory and could never store new information.

  This shows that short term memory and long term memory are separate unitary stores as describes in the MSM.
• Limitation of the MSM

  Too simplistic For example the MSM states that stm is a unitary store(there’s only 1 type) however evidence from people suffering clinical amnesia shows this can’t be true, research evidence has shown that there are several types of long-term memory; procedural, episodic and semantic.For example patient KF whose stm started forgetting more auditory information then visual information suggesting the stm is made up of multiple components, undermining the MSM.
• Strength of the MSM

  Supporting research evidence from lab studies For example peterson and peterson’s research shows that stm has a limited duration when rehearsal is prevented.

  Showing stm has a limited duration as shown in the MSM as being 18-30 seconds.

  Baddley’s research also supports the MSM as it shows participants made significantly more mistakes on words that were acoustically similar, showing stm is coded acoustically.

  Strength as it shows the msm is right as findings where similar to what the model proposes
• Limitation of the MSM

  Long term memory involves more than one type of rehearsal, not just maintenance. also involves elaborative rehearsal.

  Craik and Lockhart suggested that enduring memories are created by the processing you do, rather than through maintenance rehearsal.

  Craik and Tulvig also showed this through their study where participants remembered more words in the task involving elaborative processing, showing that elaborative processing is key to creating long term memories

  which undermines the MSM which only considers maintenance rehearsal
• Baddley's research - 1966

  1. Participants given 4 sets of words to recall in order

  2. For short-term memory they had to recall immediately

  3. For long-term memory they had to be recalled following a longer interval
• Short-term memory findings


  • More mistakes on words acoustically similar proving short-term memory is acoustically coded
• Long-term memory findings


  • More likely to confuse words that were semantically similar proving long-term memory is coded semantically
• Jacobs - STM and 'digit span'


  Devised a technique called the 'serial digit span' which requires participants to recall a set of digits/letters immediately after presented
• Jacobs findings


  • Found the average span for digits was 9.3 items and 7.3 for letters
  • Suggested it may have been easier to recall digits because there was only 9 numbers but 26 letters
• Strength of Jacobs study

  • Carried out in a very controlled way, with a high level of control over variables
• The capacity of short-term memory is around seven items of information
• Miller found that the span of immediate memory is about 7 items
• Often things come in 7s for example days of the week, backing up the MSM that short-term memory has a capacity of about 7 items
• Miller also noted that people can recall 5 words as well as 5 letters by chunking
• The size of the chunk can affect how many chunks you can remember, suggesting short-term memory may not be as extensive as was first thought
• Simon found that people have a shorter memory span for larger chunks, suggesting the lower end of Miller's estimate (5 items) is more accurate
• Strength of Miller's study

  • The findings are reliable, as they are backed up by psychological research, for example Jacobs
• Peterson and Peterson (1959) research on duration


  1. Aim was to investigate the duration of short-term memory, and provide empirical evidence for the MSM

  2. Participants had to recall trigrams (meaningless three-consonant syllables)

  3. To prevent rehearsal participants were asked to count backwards in 3s or 4s- known as the brown peterson technique

  4. Participants recalled after intervals of 3,6,9,12 or 18 seconds
• Peterson and Peterson findings

  • Percentage of trigrams remembered decreased from 80% at 3 seconds to 10% at 18 seconds
  • The short-term memory has a limited duration when rehearsal is prevented, and this information is lost from short-term memory through trace decay
  • The results also show the short-term memory is different from long-term memory in terms of duration, supporting the multi-store model
• Strength of Peterson and Peterson study

  • It has high internal validity due to being a lab experiment with a standardised procedure and high level of control over variables
• Bahrick et al (1975) research on duration


  1. Investigated the duration of long-term memory

  2. Nearly 400 participants aged 17-74

  3. Obtained high school yearbooks and conducted various tests including photo recognition and free recall
• Bahrick et al findings


  • Photo recognition - participants tested within 15 years of graduation were about 90% accurate, declining to 70% after 48 years
  • Free recall - after 15 years it was 60% accurate, declining to 30% after 48 years
  • Showing long-term memory can last a long time
• Strength of Bahrick's study

  • Has high external validity as it used real life meaningful memories, which are more representative of everyday life
• Working Memory Model


  Only focuses on short-term memory, seeing it as an active processor
• Strength of the Working Memory Model

  • Research support like evidence from brain damaged patients, showing short-term memory is made up of different subsystems and is not unitary
• Strength of the Working Memory Model

  • Research support from studies of dual task performance, showing separate slave systems for visual and verbal tasks
• Types of long-term memory proposed by Tulving

  • Episodic - more personal memories with specific details
  • Semantic - concerns facts taken independent of context
  • Procedural - memory for skills and procedures
• This means the wmm has still not been fully explained
• WMM


  • Cannot explain why blind people have excellent spatial awareness
• Lieberman criticises the WMM

  The visuospatial sketchpad implies all spatial info was first visual. However, Lieberman points out that blind people have excellent spatial awareness.
• This is significant because blind people have never had any visual info, so lieberman argues the vss should be separated into a visual and a spatial component.
• This is a weakness because it contradicts that the vss is a unitary store.
• Episodic memory


  More personal memories such as associations of a particular place or time
• Semantic memory


  Concerns facts taken independent of context
• Procedural memory


  Concerned with learning motor skills
• Episodic memories are declarative and explicit, they have specific details of the event, context and the emotion
• Semantic memories are declarative and explicit, they are the LTM store for our knowledge of the world which is shared by everyone
• Procedural memories are not declarative and implicit, they are the LTM store for our knowledge of how to do things usually acquired through repetition and practise
• Types of long-term memory

  • Proposed by TULVING: Episodic, semantic and procedural
• Case studies of HM and Clive Wearing support the existence of different types of long-term memory