Explanations for Forgetting

• describe proactive interference

  • old information interferes with the learning of new information
• aim of Keppel and Underwood (1962)

  investigate the effect of proactive interference on LTM
• method Keppel and Underwood (1962)

  • In an experiment that is very similar to that conducted by Peterson & Peterson (1959), participants were presented with meaningless three‐letter consonant trigrams (for example, THG) at different intervals (3, 6, 9 seconds, etc.)
  • To prevent rehearsal the participants had to count backwards in threes before recalling.
• results of Keppel and Underwood (1962)

  participants typically remembered the trigram that were presented first, irrespective of the interval length
• conclusion of Keppel and Underwood (1962)

  • The results suggest proactive interference occurred, as memory for the earlier consonants (which had transferred to LTM) interfered with the memory for new consonants, due to the similarity of the information presented.
• describe retroactive interference

  when learning of new information interferes with the recall of old information from LTM
• aim of Baddeley and godden(1977)

  investigate retroactive interference in everyday memory
• method Baddeley and Hitch (1977)

  • rugby union players who had played every match in the season and players who had missed some games due to injury
  • length of time from the start to the end of the season was the same for all players
  • players were asked to recall the names of the teams they had played against earlier in the season
• results of Baddeley and Hitch (1977)

  • players who had played the most games forgot proportionately more games than those who had played fewer games due to injury
• conclusion of Baddeley and Hitch (1977)

  concluded that this was the result of retroactive inference, as the learning of new information interfered with the memory of old information
• strength of interference theories

  • The results of Baddeley and Hitch are support by other researchers. In one research participants were given a list of ten adjectives to learn (list A). Once these adjectives were learnt, participants were then given one of six other lists (list B) to learn, which varied in terms of its similarity to the original. Found recall was worse when lists A and B were closest in similarity. This supports the idea of retroactive interference because the more similar the new material is to the previously learnt material, the greater the interference.
• limitations of interference theories

  • only explains a specific type of forgetting – memory for similar information. For example, the results of Baddeley and Hitch demonstrate retroactive interference in rugby union players trying to recall team names from earlier in the season and Keppel and Underwood demonstrate proactive interference when trying to learn three‐letter consonant trigrams. Both of these examples highlight interference effects of very similar information and therefore this research is limited in its real world application and are unable to explain forgetting in other situations.
• limitations of interference theories (1)

  • only explains a specific type of forgetting – memory for similar information. Both of these examples highlight interference effects of very similar information and therefore this research is limited in its real world application and are unable to explain forgetting in other situations.
• limitations of interference theories (2)

  • interference research is often criticised for being artificial and lacking ecological validity. Most of the research examining interference is carried out in a laboratory, for example Keppel and Underwood (1962) and McGeoch and McDonald (1931), while using particularly meaningless stimuli, such as three‐letter consonant trigrams or simple word lists. As a result these findings do not represent everyday examples of interference and are limited in their application to everyday human memory.
• What is retrieval failure due to absence of cues?

  When information cannot be retrieved because of insufficient cues to trigger memory
• what is context-dependent forgetting?

  when environmental cues are missing
• what is state-dependent forgetting?

  when the emotional state than an individual is in serves as an aid to memory recall
• aim of Godden and Baddeley (1975)

  to investigate the effect of contextual cues on recall
• method of Godden and Baddeley (1975)

  • 18 participants (13 males and 5 females)
  • four conditions:

  1. learning words on land and recalling on land
  2. learning words on land recalling underwater
  3. learning underwater and recalling underwater
  4. learning underwater and recalling on land
• method of Godden and Baddeley (1975)

  • 18 participants (13 males and 5 females)
  • four conditions:

  1. learning words on land and recalling on land
  2. learning words on land recalling underwater
  3. learning underwater and recalling underwater
  4. learning underwater and recalling on land

  • repeated measures design with each participant taking part in all 4 conditions
  • in all 4 conditions each participant was presented with 38 words
  • after hearing all 38 words the participants were instructed to write all the words they could remember
• results of Godden and Baddeley (1975)

  • words learned underwater were better recalled underwater and words learned on land were better recalled on land

  
• limitations of context-dependent forgetting (1)

  • Godden & Baddeley didn’t control many other variables. The divers took part in the experiment at different times of the day and at different diving locations. Therefore, each diver would have experienced other contextual cues, which may have affected their memory. Therefore, we are unable to conclude whether the results of Godden & Baddeley’s research is due to the on land/underwater contextual cues, or another contextual cue provided by the different time of day or diving location.
• limitations of Context-Depending Forgetting

  • Godden & Baddeley used a repeated measures design, as each diver took part in all four conditions. It is possible that the divers worked out the aim of the experiment and displayed demand characteristics or order effects. A more suitable experimental design would have been independent measures. However, this would have required significantly more participants, which would be difficult to achieve when recruiting trained divers.
• limitations of Context-Dependent Forgetting (3)

  • Godden & Baddeley could also be criticised for breaking ethical guidelines, in particular protection from harm. In their report, they said: ‘One diver was nearly run over during an underwater experimental session by an ex‐army, amphibious DUKW’, and therefore more precautions should have been taken to ensure the safety of their participants.
• method of Carter and Cassady (1998)

  • Participants were tasked with learning a list of words and excerpts from a text and then asked to recall the information at a later point. There were four conditions in their experiment:

  1. learn the words/text after taking anti-histamine and recall after taking anti-histamine
  2. learn the words/text without anti-histamine and recall without anti-histamine
  3. learn the words/text after taking anti-histamine and recall without anti-histamine drugs
  4. learn the words/text without anti-histamine and recall after taking the anti-histamine drugs
• results of Carter and Cassady (1998)

  • in the conditions where the learning and recalling state matched memory was improved
  • consequently, when the physiological state of the participants was different recall was significantly poorer
• conclusion of Carter and Cassady (1998)

  when the physiological/emotional cues that are present at the time of encoding are missing at the time of retrieval, state-dependent forgetting is likely to occur
• limitations of interference theories (3)

  • Baddeley & Hitch’s (1977) research showed gender bias. They investigated retroactive interference using an all‐male sample of rugby players and then applied their findings outside of this target population to include females. This is an example of a beta‐bias, which occurs when researchers minimise possible differences between females and males and assume that research carried out on one gender may be universally applied to the other.
• strength of state-dependent forgetting

  • There is research support for the effect of state‐dependent retrieval failure. Goodwin et al. (1969), asked male volunteers to remember lists of words when they were either drunk or sober. The participants were then asked to recall the words 24 hours later, in either a drunk or sober state. The results support, as words learned when drunk were better recalled when drunk, and words learnt when sober were better recalled when sober. Support the idea of state‐dependent retrieval failure and demonstrate the power of ‘state’ on recalling information.
• limitations of state-dependent forgetting

  • issues with determining a cause and effect relationship with retrieval failure as an explanation of forgetting. criticised for a correlation between cues present at the time of encoding and cues present at the time of later retrieval. cues present do not in themselves cause the retrieval failure (or success), but are simply associated with it. This would mean that the cue‐dependent explanations of forgetting due to retrieval failure is unable to conclude whether a lack of cues actually causes retrieval failure.
• limitation of retrieval failures due to absence cues

  • The theories of forgetting use a nomothetic approach to establish general laws regarding forgetting, but often by generalising from small studies with homogeneous samples. An idiographic approach investigating forgetting using participants of difference ages and cultures may give more insight into this complex phenomenon.