CHAPTER 2: MEMORY Flashcards
Summarise Alan Baddely’s research on encoding.
Alan Baddeley (1966a, 1966b) gave different lists of words to four groups of participants to remember: • Group 1 (acoustically similar) • Group 2 (acoustically dissimilar) • Group 3 (semantically similar) • Group 4 (semantically dissimilar)
Participants were shown the original words and asked to recall them in the correct order. When they had to do this recall task immediately after hearing it (STM recall), they tended to do worse with acoustically similar words. If participants were asked to recall the word list after a time interval of 20 minutes (LTM recall), they did worse with the semantically similar words. This suggests that information is coded semantically in LTM.
AO3:
- Artificial material so it cannot be generalised to all memory tasks.
- It was a volunteer sample.
Summarise Joseph Jacobs study on digit span.
Joseph Jacobs (1887) developed a technique to measure digit span. The researcher gives, for example, 4 digits and then the participant is asked to recall these in the correct order out loud. If this is correct the researcher reads out 5 digits and so on until the participant cannot recall the order correctly. This determines the individual’s digit span. Jacobs found that the mean span for digits across all participants was 9.3 items. The mean span for letters was 7.3.
AO3
- It was done a long time ago and may have lacked adequate control
- It is easy replicable
Summarise Harry Bahrick’s study on duration of LTM.
Harry Bahrick and colleagues (1975) studied 392 participants from the American state of Ohio who were aged between 17 and 74. High school yearbooks were obtained from the participants or directly from some schools. Recall was tested in various ways, including: (1) photo-recognition test consisting of 50 photos, some from the participant’s high school yearbook (2) free recall test where participants recalled all the names of their graduating class.
Participants who were tested within 15 years of graduation were about 90% accurate in photo recognition. After 48 years, recall declined to about 70% for photo recognition.
Free recall was less good than recognition. After 15 years this was about 60% accurate, dropping to 30% after 48 years. This shows that LTM can last a very long time indeed.
AO3:
- High external validity as real-life memoirs studied
- Confounding variables not measured, such as how often the participants have looked at the yearbook
Summarise Peterson and Petersons’ study on STM.
Margaret and Lloyd Peterson (1959) tested 24 undergraduate students. Each student took part in eight trials. A ‘trial’ is one test. On each trial the student was given a consonant syllable (also known as a trigram, such as YCG) to remember and was also given a 3-digit number. The student was then asked to count backwards from that 3-digit number until told to stop. This counting backwards was to prevent any mental rehearsal of the consonant syllable (which would increase the student’s memory for the consonant syllable). On each trial they were told to stop after a different amount of time - 3, 6, 9, 12, 15 or 18 seconds. This is called the retention interval. Their findings are shown in the graph on the left. It suggests that STM may have a very short duration indeed, unless we repeat something over and over again (i.e. verbal rehearsal).
AO3:
- Cannot generalise to all memory because of articulation material
- Application to remembering phone numbers etc
What is the multi-store model (MSM)?
It was created by Atkinson and Shiffin (1968)
Sensory register - The memory stores for each of our five senses, such as vision (iconic store) and hearing (echoic store). Coding in the iconic sensory register is visual and in the echoic sensory register it is acoustic. The capacity of sensory registers is huge (millions of receptors) and information lasts for a very short time (less than half a second).
Short-term memory (STM) - STM is what is known as a limited capacity store, because it can only store 7 ‡ 2 items. Information in STM is coded acoustically and lasts about 30 seconds unless it is rehearsed. Maintenance rehearsal occurs when we repeat material to ourselves over and over again. We can keep the information in our STMs as long as we rehearse it. If we rehearse it long enough, it passes into long-term memory (LTM).
Long-term memory (LTM) - This is the potentially permanent memory store for information that has been rehearsed for a prolonged time. Psychologists believe that its capacity is unlimited and can last many years. We also saw that LTMs tend to be coded semantically (i.e. in terms of meaning). Although this material is stored in LTM, when we want to recall it, it has to be transferred back into STM by a process called retrieval. According to the MSM, this is true of all our memories. None of them are recalled directly from LTM.
Evaluate the multi-store model (MSM).
Strengths:
- There is a large base of research that supports the idea of distinct STM and LTM systems (e.g. brain-damaged case study patient KF’s STM was impaired following a motorcycle accident, but his LTM remained intact.
The MSM was a pioneering model of memory that inspired further research and consequently other influential models, such as the Working Memory Model.
Weaknesses:
- Some research into STM duration has low ecological validity, as the stimuli participants were asked to remember bear little resemblance to items learned in real life, e.g. Peterson and Peterson (1959) used nonsense trigrams such as ‘XQF’ to investigate STM duration.
- The model is arguably over-simplified, as evidence suggests that there are multiple short and long-term memory stores, e.g. ‘LTM’ can be split into Episodic, Procedural and Semantic memory.
What is episodic memory?
A long-term memory store for personal events. It includes memories of when the events occurred and of the people, objects, places and behaviours involved. Memories from this store have to be retrieved consciously and with effort.
What is semantic memory?
A long-term memory store for our knowledge of the world. This includes facts and our knowledge of what words and concepts mean. These memories usually also need to be recalled deliberately.
What is procedural memory?
A long-term memory store for our knowledge of how to do things. This includes our memories of learned skills. We usually recall these memories without making a conscious or deliberate effort.
What is the working memory model (WMM)?
The working memory model (WMM) is an explanation of how one aspect of memory (short-term memory) is organised and how it functions. The WMM is concerned with the part of the mind that is active when we are temporarily storing and manipulating information. The model consists of:
Central executive
The central executive is essentially an attentional process that monitors incoming data makes decisions and allocates slave systems to tasks. The central executive has a very limited processing capacity.
Phonological loop
One of the slave systems is the phonological loop (PL). It deals with auditory information (i.e. coding is acoustic) and preserves the order in which the information arrives. It is subdivided into:
• The phonological store, which stores the words you hear.
• The articulatory process, which allows maintenance rehearsal. The capacity of this “loop’ is believed to be two seconds.
Visuo-spatial sketchpad
The VSS stores visual and/or spatial information when required. For example, if you are asked to work out how many windows there are on your house you visualise it. It also has a limited capacity (three or four items). It is subdivided into:
• The visual cache, which stores visual data.
• The inner scribe, which records the arrangement of objects in the visual field.
Episodic buffer
It is a temporary store for information, integrating the visual, spatial, and verbal information processed by other stores and maintaining a sense of time sequencing basically recording events (episodes) that are happening. It can be seen as the storage component of the central executive and has a limited capacity of about four chunks The episodic buffer links working memory to LTM and wider cognitive processes such as perception.
Evaluate the working model memory (WMM).
Strengths:
- The WMM provides an explanation for parallel processing (i.e. where processes involved in a cognitive task occur at once), unlike Atkinson and Shiffrin’s MSM.
- A Shallice and Warrington (1974) case study reported that brain-damaged patient KF could recall verbal but not visual information immediately after its presentation, which supports the WMM’s claim that separate short-term stores manage short-term phonological and visual memories.
- The model was developed based on evidence from laboratory experiments, so confounding variables could be carefully controlled to produce reliable results (that can be replicated).
Weaknesses:
- Despite providing more detail of STM than the multi-store model, the WMM has been criticized for being too simplistic and vague, e.g. it is unclear what the central executive is, or its exact role in attention.
- Results from laboratory experiments researching the WMM will often have low ecological validity (i.e. may not relate to real life), as tasks such as repeating ‘the the the’ are arguably not representative of our everyday activities.
What is the interference theory for forgetting?
Interference is forgetting because one memory blocks another, causing one or both memories to be distorted or
forgotten. Proactive interference is when forgetting occurs when older memories, already stored, disrupt the recall of newer memories. The degree of forgetting is greater when the memories are similar. Retroactive interference (RI) is when forgetting occurs when newer memories disrupt the recall of older memories already stored. The degree of forgetting is again greater when the memories are similar.
Summarise McGeoch and McDonald’s research on interference.
Procedure:
McGeoch and McDonald studied retroactive interference by changing the amount of similarity between two sets of materials. Participants had to learn a list of 10 words until they could remember them with 100% accuracy. They then learned a new list. There were six groups of participants who had to learn different types of lists.
Findings:
When the participants then recalled the original list of words, their performance depended on the nature of the second list. The most similar material (synonyms) produced the worst recall. This shows that interference is strongest when the memories are similar.
AO3:
- It is a lab study so cannot be generalised to all memory.
- It is an artificial task so cannot be applied to real life.
What is the retrieval failure explanation for forgetting?
Retrieval failure is when the necessary cues are not present to access a memory.
Context-dependent forgetting (external cues)
Duncan Godden and Alan Baddeley (1975) carried out a study of deep sea divers working underwater. The procedure in this study were that the divers learned a list of words either underwater or on land and then were asked to recall the words either underwater or on land. This created four conditions. Findings were that accurate recall was 40% lower in the non-matching conditions. The external cues available at learning were different from the ones at recall and this led to retrieval failure.
State-dependent forgetting (internal cues)
Procedure was that Sara Carter and Helen Cassaday (1998) gave anti-histamine drugs to their participants. The anti-histamines made the participants drowsy. This creates an internal physiological state different from the ‘normal’ state. The participants had to learn lists of words and passages of prose and then recall the information, again creating four conditions. Findings were that in the conditions where there was a mismatch between internal state at learning and recall, performance on the memory test was significantly worse. So when the cues are absent then there is more forgetting.
AO3:
- The study has limited ecological validity because the tasks are artificial.
- It was a controlled experiment so can be replicated.
- Real life applications for cognitive interviews with the police
