- Created by: msahay
- Created on: 31-05-19 11:54
Multi Store Memory (MSM)
explanation that sees memory as flowing through a series of storage systems.
made up of 3 distinct stores: sensory register (SR), short-term memory (STM) and long-term memory (LTM)
Each differs in terms of:
- coding - form in which info is stored
- capacity - how much info can be stored
- duration - how long info can be stored for
Info from sense organs ---> sensory register ---> info that is paid attention to ---> short term memory ---> rehearsal of info in short-term memory ---> transferred to long-term memory
Sensory Register (SR)
Short duration store holding sensory information
Coding - Info is stored in an unprocessed form with separate sensory stores within the SR for different sensory inputs e.g. iconic store for visual info (modality specific)
Capacity - very large - contains highly detailed, unprocessed info
Duration - information from the senses that enters the SR remains there for split seconds. Though, different sensory stores within the SR have different durations.
Crowder found that SR retains info in the iconic store for a few milliseconds but for 2-3 in the echoic store, supporting the idea that different sensory stores have different durations.
Short-Term Memory (STM)
Temporary store holding small amounts of information for brief periods
Coding - Information arrives into the STM as unprocessed. In the STM, this information is coded visually, acoustically or semantically.
Baddeley found that similar sounding words are the hardest to recall immediately after learning, suggesting that information in the STM is coded primarily acoustically.
Capacity - limited capacity of 5-9 items, can be increased by chunking
Duration - max of 30 seconds without rehearsal (active thinking) that transfers information to the LTM.
Long-Term Memory (LTM)
Permanent store holding large amounts of information for longer periods
Coding - mainly semantic, coding of info is stronger and memory more retrievable if processing level is high
Capacity - unlimited capacity - info may be lost due to decay or interference but not because of capacity
Wagenaar found he had excellent recall of events in his diary he kept for 6 years.
Duration - Items in LTM have a longer duration if well coded, and procedural LTMs also have a longer duration.
The model is supported by real life cases of amnesia. Patient HM suffered from anterograde amnesia which resulted in him being able to remember things he had just been told (suggesting his STM was intact) but could not transfer this information to the LTM (he read the same magazine many times). This partial functioning of memory in Patient HM gives evidence for STM and LTM being two separate and distinct memory stores like the MSM proposes, therefore validating it as a memory model.
MSM is now regarded as a basic model that oversimplifies the structures and processes of memory. The WMM suggests that STM actually has several separates memory stores within in that codes differently for visual and acoustic information, as opposed to the one MSM suggests as well as different types of LTM. This alternative model challenges MSM's simplicity and so undermines its validity as a wholly correct model for memory.
Patient KF contradicts MSM. They were unable to code acoustic information into their STM yet had a normal ability to code visual information. This distinction in the STM itself, suggests that there are different memory stores more complex than the singular set up suggested by MSM.
Interference Theory (IT)
an explanation for forgetting when similar material is confused in recall from the LTM.
Info stored previously intereferes with the attempt to recall of new info e.g. an old telephone memory interfering with the recall of a new one.
When the coding of new information intereferes with the attempt to recall previously stored info e.g. the memory of a new license plate interfering with the recall of an old one.
Baddeley asked participants who had played a varying number of rugby games to recall all the names of teams they had played in previous season. The more games a player had played, the poorer the recall. This provides evidence for interference theory as opposed to decay theory because competing information from earlier on in the season interfered with the player's recall (proactive interference)
Interference Theory (IT) Evaluation
Many interference theory studies suffer from a lack of ecological validity - they are based around artificial taks such as learning word lists. Participants may not be motivated to recall these pointless memories as they would for other memories in the real world. This may make interference effects appear worse than they are in real-life situations and thus not provide an accurate picture of why we forget.
A criticism of interference theory is that it only really explains forgetting when two sets of info are similar e.g. learning French and German at school. This sort of similarity learning does not happen very often in real-life so interference theory cannot explain forgetting in the majority of real-life settings, weakening it as an explanation for forgetting.
There is more research support for retrieval failure, and other explanations of forgetting exist too, meaning IT cannot explain all examples of forgetting.
Danaher - if you can remember it (practical applications for time and money spent on adverts)
an explanation of forgetting that sees forgetting as a result of not being able to locate the correct retrieval cue to jog the memory.
Retrieval cue - prompt that allows a certain memory to be recalled e.g. a person's initials acts as a retrieval cue for their name
Context dependent forgetting - when the place/situation where memory was coded is different to recall, there is a lack of context retrieval cues which can lead to info being forgotten
Badden and Goddeley found that a group of scuba divers who learnt words underwater had better memory recall of these words later on underwater than on land. Demonstrates how recall is better when the context at coding matches that at recall.
State-dependent forgetting - when the individual's emotional/psychological state that memory was coded in is different at recall, there is a lack of state retrieval cues which can lead to information being forgotten.
Godwin asked volunteers to learn a list of words either drunk or sober. Each group later showed better memory recall when they were in the same state in which they originally learnt the words. Demonstrates how recall is better wheninternal state at coding matches recall.
Retrieval Failure Evaluation
Many psychologists see retrieval failure as the main reason for forgetting in the LTM due to the amount of research evidence supporting the importance of cues and how they trigger memories. This has potentially important applications in, for example, exams. Although it is unrealistic to expect that you could be taught and examined in the same room, it has been shown that using imagination to visualise the room you were taught in can aid memory recall. (recreating the environment in which info was originally coded)
Cue dependent forgetting is supported by the Levels of Processing theory that states that the better a memory is coded, the more links will be created in the LTM, decreasing chances of forgetting, as more retrieval cues will be available for recall aid.
Psychologists see cue dependent forgetting as the main reason for forgetting in LTM due to the numerous research evidence supporting this explanation.
Cue dependent forgetting studies often have artificial memory tasks such as learning word lists therefore, they suffer from a lack of ecological validity.
Eyewitness Testimony (EWT)
evidence provided by recalling an event by those who were present when an event took place.
THE INFLUENCE OF SCHEMA
Bartlett argued that memories are reconstructions of events, influenced by schemas (expectations based on previous experience, knowledge and emotions used to fill in gaps during info processing)
This affects the reliability of EWT as witnesses are not recalling info but essentially reconstructing memories based on biased schemas - which can be subject to inaccuracy + confabulatuon
Bartlett found that when Western participants were told a traditional Navajo Indian story that didn't make sense from their perspective, their memory of the story became distorted as they changed details to fit a Western viewpoint. Illustrates how memory can be affected by cultural schemas.
Factors affecting EWT: LEADING QUESTIONS
A leading question is one which suggests to the witness what answer is desired or leads them to the desired answer e.g. "you shot X that night didn't you?".
Loftus and Palmer's car crash study:
AIM: assess the extent to which participants' estimates of car speed in video accidents could be influenced by leading questions.
45 student participants watched 7 videos of car crashes and were then asked to fill out a questionnaire.
Different groups of participants were given 5 variations of 1 critical question, regarding the car's speed. "How fast were the cars going when they smashed/collided/bumped/hit/contacted"?
Mean speed of "smashed" was 40.8mph. Mean speed of "contacted" was only 31.8mph
Misleading information in the form of leading questions can distort recall of events.
Factors affecting EWT: LEADING QUESTIONS (cont)
Loftus and Palmer's research seems reliable - findings have been reproduced through subsequent experimentation e.g. Loftus and Zanni.
Loftus and Palmer's studies were lab experiments based on artificial tasks (watching videos) that lack relevance to real-life, lowering ecological validity. Witnessing a real car crash would be more emotionally arousing and would affect recall differently so the extent to which results can be generalised is debatable.
Findings may be due to demand characteristics, rather than genuine changes in memory. Participants may just have given an answer they thought the researchers wanted as suggested by the verb they heard in the question. Participants do not expect to be deliberately mislead by researchers - therefore, inaccurate recall should be expected.
Studies of EWT that use potentially distressing stimuli bring ethical concerns of psychological harm. Care should be taken not to include participants of traumatic car accidents, for example.
Factors affecting EWT: ANXIETY
a negative emotional state associated with high levels of physiological and psychological arousal (such as might be experienced whilst witnessing a crime)
Deffenbacher's meta-analysis of 21 studies that looked at the effect of heightened anxiety on accuracy of EWT and found that high anxiety negatively impacts eye-witness testimony.
However, Christensen found contradictory results. 58 witnesses of real-armed bank robberies were interviewed 4-15 months after the incident. Witness that had been threatened in some way (and thus experienced high anxiety) were more accurate and detailed in their recall than bystanders. This also lends support to the concept of "flashbulb" memories - where intense emotional experiences create a stronger, highly detailed memory trace.
Contradictory findings. This contradiction of whether high levels of anxiety negatively affect recall of memory could be explained by the inverted-U hypothesis.This ties in with mediating factors such as personality that play a role too e.g. each individual has a different optimum level of anxiety and also react differently to anxiety-creating situations. Therefore, it is very hard to pinpoint exactly how anxiety will affect memory recall.
Cognitive Interview (CI)
police procedure used for the questioning of witnesses - designed for more accurate and detailed recall of events.
Change of narrative order - witness recalls event in varying orders e.g. from end to star of event. Memories are influenced by our schemas (ready made expectations) so by changing the order we can disrupt these schemas and increase memory recall.
Change of perspective - witness recalls event from different perspective's e.g. the offender's viewpoint. By varying the routes through which info has been observed, it may increase memory recall.
Mental reinstatement of context - witness mentally recalls physical and psychological details about event e.g. weather or feelings. Context and state-dependent cues can be a trigger for more important memories about the event and thus, increase memory recall.
Report everything - witness recalls all information. As all memories are interconnected, an insignificant memory can act as a retrieval cue for a more important one.