LTM AO3
+ brain scans
+ patient HM - implicit intact, explicit affected, shows distinction between the two
+ patient PM - amnesia, explicit affected, implicit intact
+ real world app - Belleville et al: memory training programmes improved episodic memory in ppl whose cognitive impairments could lead to dementia. Helps delay cognitive decline
WMM AO3
+ patient KF - remembered visual images not sounds
+ dual task studies
- only focuses on STM
proactive interference: Keppel & Underwood (1962)
- 3 letter trigrams
- count back to prevent rehearsal
- ppts remembered those shown first
- proactive int occurred as memory for earlier consonants interfered with the memory for new ones due to the similarity
Retroactive interference: Baddeley & Hitch (1977)
- rugby union players who had played every match in the season and players who had missed some games due to injury.
- Players were asked to recall the names of the teams they had played against earlier in the season.
- The players who had played the most games forgot proportionately more games than those who had played fewer games due to injury.
- concluded that this was the result of retroactive inference, as the learning of new information (new team names) interfered with the memory of old information (earlier team names).
interference theories ao3
+ support for retroactive from McGeoch and McDonald. found that recall of lists A and B was worst when they were the closest in similarity
- only explains one type of forgetting (memory for similar info)
- lacks eco validity
context dependent forgetting: Godden & Baddeley
- Participants learned words on land or underwater and recalled them on land or
underwater. - The words learned underwater were beter recaled underwater and words learned on
land were better recalled on land. - reasonable to conclude that the environmental cues (context)
improve recall.
context dependent forgetting ao3
- didnt control other variables (divers took part on different days at different times)
- repeated measures, demand characteristics
- broke ethical guidelines, one ppt almost run over by an ex army DUKW
State dependent forgetting: Carter & Cassaday
- 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 talking anti-histamine and recall without anti-histamine drugs 4) learn
the words/text without anti-histamine and recall after taking the anti-histamine drugs - In the conditions where the learning and recalling state matched (i.e. after taking the
drugs on both occasions or not taking the drugs both occasions) memory was improved.
Consequently, when the physiological state of the participants was different recall was
significantly poorer. - When the physiological/emotional cues that are present at the time of encoding are
missing at the time of retrieval (recall), state-dependent forgetting is likely to occur.
State dependent forgetting ao3
+ support from Goodwin et al: drunk or sober
+ support from Darley et al: marijuana and safe place
- role of other factors: Retrieval failure does not account for forgetting caused by decay or interference, which may also contribute to retrieval difficulties.
EWT: Leading questions exp 1 - Loftus and Palmer (1974)
- Participants watched a video of a car crash and were then asked a specific question
about the speed of the cars. Loftus & Palmer manipulated the verb used in the question. - The estimated speed was affected by the verb used.(smashed- 41%, contacted- 31%)
- The results show clearly that the accuracy of eyewitness testimony is affected by
leading questions and that a single word in a question can significantly affect the accuracy of our
judgements.
EWT: Leading questions exp 2 - Loftus and Palmer (1974)
- Participants watched a video depicting a car accident and were then given a questionnaire to complete. One group was asked: “How fast were the cars going when they
smashed into each other?” Another group was asked: “How fast were the cars going when they
hit each other?” The final group (control) was not asked about the speed of the vehicles. - 32% of the participants who were previously questioned using the verb smashed reported seeing broken glass; 14% of the participants who were previously questioned using the verb hit reported seeing broken glass; and 12% of the control group reported seeing broken
glass. - The participants who were questioned previously using the verb smashed were
significantly more likely to report seeing the broken glass, as a result of the earlier leading question
Loftus & Palmer ao3
- low eco validity, irl you rarely witness the whole event
- low pop validity
+ highly controlled, uni lab, low EV
EWT: post-event discussion - Gabbert et al
- Participants watched a video of a girl stealing money from a wallet. The participants were either tested individually (control group) or in pairs (co-witness group). The participants in the co-witness group discussed the crime together.
- 71% of the witnesses in the co-witness group recalled information they had not actually seen and 60% said that the girl was guilty, despite the fact that they had not seen her commit a crime.
- These results highlight the issue of post-event discussion and the powerful efect
this can have on the accuracy of eyewitness testimony.
Gabbert et al ao3
- low eco validity: aware of the experiment
+ high pop validity: students and adults - unable to conclude why the distortion occurs
EWT: Anxiety - Loftus / Johnson & Scott
- Participants were invited to a laboratory where they were told to wait in the reception area. The experiment used an independent groups design, as participants were then exposed to
one of two conditions: 1) In the ‘no-weapon’ condition, participants overheard a conversation in the laboratory about equipment failure. Thereafter, an individual (the target) left the laboratory
and walked past the participant holding a pen, with his hands covered in grease. 2) In the weapon’ condition, participants overheard a heated exchange and the sound of breaking glass and crashing chairs. This was followed by an individual (the target) running into the reception area, holding a bloodied letter-opening knife. - Those who had witnessed the man holding a pen correctly identified the target 49% of
the time, compared to those who had witnessed the man holding a knife, who correctly identified
the target 33% of the time. - Loftus claimed that the participants who were exposed to the knife had higher levels of anxiety and were more likely to focus their attention on the weapon and not the face of the target, a phenomenon known as the weapon focus effect. Therefore, the anxiety associated with seeing a knife reduces the accuracy of eyewitness testimony.
Loftus / Johnson & Scott ao3
- Yuille & Cutshall contradict
- low eco validity
- broke ethical guidelines
cognitive interview: Geiselman (1985)
- A sample of 89 students watched a video of a simulated crime. Two days later the students were interviewed using the standard police interview or the cognitive interview.
- The students who were interviewed using the cognitive interview recalled significantly more corect information than those interviewed using the standard interview. In addition, the
number of errors (incorrect items recaled) by both groups was similar. - The cognitive interview is effective in improving the quantity of information
recaled and does not lead to an increase in incorrect information.
Geiselman (1985) ao3
+ support from Fisher et al
- Kebbel & Wagstaff: police officers still use interviewing techniques that limit the quantity of info provided rather than those that improve accuracy
- Centofanti & Reece: still susceptible to misleading info
peterson and peterson a03: small sample
P: Peterson & Peterson used a sample of 24 psychology students, which is an issue for two reasons.
Firstly, the psychology students may have encountered the MSM of memory previously and therefore
may have demonstrated demand characteristics by changing their behaviour to assist the
experimenter. Secondly, the memory of psychology students may be different from that of other
people, especially if they had previously studied strategies for memory improvement. As a result we
are unable to generalise the results of this study to non‐psychology students.
E: One limitation of Peterson & Peterson’s study is that it used a very small, specific sample.
E: The study only included 24 psychology students.
D: This is a limitation because psychology students may already be familiar with memory theories, such as the Multi-Store Model, and might show demand characteristics by altering their behaviour to please the experimenter.
features of sensory register
Capacity: Unknown, but very large
Duration: Very limited
(approximately 250 ms
Coding: Raw/unprocessed information
(from ALL 5 senses)
features of STM
Capacity: Limited (7+/‐2 ‘chunks’ of
information)
Jacobs (1887)
Miller (1956)
Duration: Limited (20 seconds)
Peterson & Peterson (1959
Coding: Acoustic (Sound)
Baddeley (1966)
features of LTM
Capacity: Unlimited
Duration: Lifetime/Years
Bahrick (1975)
Coding: Semantic (Meaning)
Baddeley (1966)
Key Study: Miller (1956)
Capacity of STM
- Miller (1956) aimed to investigate the capacity of short‑term memory (STM).
- He conducted a literature review of studies on perception and STM from the 1930s–1950s.
- Miller found that STM capacity is typically around 7 items, plus or minus 2.
- He argued that people can remember more information by chunking items into meaningful units.
- Chunking allows STM to handle about seven chunks, explaining how long strings (e.g., phone numbers) can be recalled.
- Miller concluded that organisation/encoding can extend STM capacity, allowing more information to be briefly stored.
Miller AO3: Research support
P: Miller’s (1956) theory about the capacity of short‑term memory is supported by further psychological research.
E: For example, Jacobs (1887) conducted a digit‑span experiment where participants had to recall increasingly long strings of numbers or letters. Using a large sample of 443 female students, he found an average span of 7.3 letters and 9.3 digits.
E: This supports Miller because Jacobs’ findings fall within the 7 ± 2 range, showing that STM capacity consistently clusters around seven items, just as Miller proposed.
D: increases the reliability and validity of Miller’s conclusions, as independent research using different methods and participants produces similar results.
