Memory
Multi-Store Model
Atkinson and Shiffrin (1968)
Sensory Memory
- Coding: Modality Specific (senses).
- Capacity: very high.
- Duration: Less than half a second
Short Term Memory
- Coding: Acoustically
- Capacity: 5-9 items
- Duration: Around 18 seconds
Long Term Memory
- Coding: Semantically
- Capacity: Practically unlimited
- Duration: Potentially a lifetime.
Evaluation
Research on Coding
- Baddeley (1966): groups were given, a) acoustically similar, b) acoustically dissimilar, c) semantically dissimilar word lists.
Those who recalled immediately (STM) found the acoustically similar words harder to recall.
Those who recalled 20 minutes later (LTM) found the semantically similar words harder to recall.
Research on Duration
- Peterson & Peterson (1959): Gave students trigrams to remember (e.g. TGH) and asked them to recall them after certain intervals, 3, 6, 9, 12, 15, 18, 21. After hearing the trigram they were asked to count back from a given number.
The study demonstrated that the longer the participant was asked to count from, the less they were likely to recall the trigram accurately.
Research on Capacity
- Jacobs (1887) read out increasing numbers of digits and asked participants to recall the until they could no longer remember correctly.
- Miller (1956) find that the capacity of short term memory is around 5-9 items but can be increased through chunking.
Case study - KF: had a motorbike accident and his STM was impaired but not his LTM. His memory for digits was poor when read out loud to him it was better when he read them out himself. He seemed to still have STM for visual material, suggesting there may be more than one STM store.
ELaborative Rehearsal
- Craik & Watkins (1973): Stated that it was the type of rehearsal that was more important. Therefore, the multi-store model does not effectively explain how some memories transfer more quickly than others.
Working Memory Model
Central Executive
- Drives the system and decides how attention is directed.
- It allocates the slave systems to tasks.
- It has no storage capacity and limited processing capacities.
Visuo-Spatial Sketchpad
- Stores visual and spatial information.
Phonological Loop
- Deals with auditory information.
- Stores the words you hear.
Episodic Buffer
- General Storage Space for the other stores and it integrates information from these and the LTM.
- Limited capacity: 4 chunks.
Baddeley and Hitch (1974)
Evaluation
Dual Task Performance
- Doltos et a. (2007), showed effects of dual task performance using fMRI scans.
- Different areas of the prefrontal cortex were activated when performing 2 tasks affecting the same store than when completing 2 tasks from different stores.
Central Executive - There is little clarification as to what the Central Executive's role is.
Case Study - KF: He seemed to still have STM for visual material, supporting the existence of separate visual and acoustic memory stores.
Cognitive Interview
Long-Term Memory
Types of LTM
Episodic - Explicit memories of events.
Semantic - Memory for facts and knowledge.
Procedural - Memory of how to do things.
Evaluation
Tulving (1989) - Found that the volunteers who had their brains scanned when using their episodic memory their frontal cortex was active. When using their semantic memory the back cortex was active.
Real World Application - Belleville et al. (2006), devised an intervention to improve episodic memory in older people.
Clive Wearing - Had impaired episodic impairment from a viral infection but his semantic and procedural memories were intact as he could still understand meanings of words and play the piano.
Techniques
Report everything.
Mental Reinstatement of original context (Imagine the environment).
Recall Events in a different order
Change Perspectives.
Geiselman (1999) - Children under the age of six reported things slightly less accurately when interviewed using the CI.
How effective? Milne and Ball (2002) - Police officers report that recall is similar across each one but found it improved with a combination of report everything and reinstatement.
Kohnken et al. (1999) - Conducted a meta-analysis of 53 studies. They found cognitive Interviews increased the amount of accuracy by 34% compared to standard interviewing.
Explanations for Forgetting
Retrieval Failure
Covert-Dependent Forgetting: Abernathy (1940)
- Tested students each week in the same or different rooms and same or different instructions. These in the same room with same instructor did best.
State-Dependent Forgetting, Hardman (1998)
- Found that those who learnt a list of words on an exercise bike could remember them better when exercising again.
Encoding Specificity Principle
- A cue has to be present at retrieval for it to aid memory.
Evaluation
State: Goodwin et al. (1969) - People who were drunk when learning words had better recall when drunk again.
Real World Application - We can use strategies to improve our recall in our daily likes by trying to match context or state.
Divers - If divers learnt a list of words underwater or on land and then recalled them on water or on land. Recall was better when the context matched recall.
Interference
Proactive Interference - An old memory trace disrupts new information.
Retroactive Interference - New information interferes with an old memory.
Evaluation
Baddeley & Hitch (1977)
- Rugby players.
- Those who played the most games forgot more.
Tulving & Putoka (1971)
- Gave participants lists of words in categories.
- The more lists they were given the worse the recall.
- But if they were given the names of the categories recall improved.
Underwood (1957)
- Asked students to learn nonsense syllables and found that a group that had taken part in earlier memory experiments were more likely to forget the new life.