MEMORY Flashcards
Define Capacity
A measure of how much can be held in memory. It is represented in terms of bits of information such as number of digits
Define Coding
The way information is changed so that it can be stored in memory. Information enters the brain via the senses (e.g. eyes and ears). It is then stored in various forms, such as visual codes (like a picture), acoustic codes (sounds) or semantic codes (the meaning of the experience)
Define Duration
A measure of how long a memory lasts before it is no longer available
Define Long-term memory (LTM)
Your memory for events that have happened in the past. This lasts anywhere from 2 minutes to 100 years. LTM has potentially unlimited duration and capacity and tends to be coded semantically
Define Short-term memory (STM)
Your memory for immediate events. STMs are measured in seconds and minutes rather than hours and days i.e. a short duration. They disappear unless they are rehearsed. STM also has a limited capacity of about four items or chunks and tends to be coded acoustically. This type of memory is sometimes referred to as working memory
Describe research that has investigated capacity in STM
- Jacobs (1887) used digit span to assess capacity (consisted of multiple columns and as you progressed there were more digits and letters than the last that you had to say, the close your eyes and remember)
- Found that the average space for digits was 9.3 items and 7.3 for letters
- Jacobs theorised it may have been easier to memories digits since there are only 9 digits but 26 letters
- Miller (1956) reviewed psychological research and concluded that the span of immediate memory is about 7 items - sometimes a bit more, sometimes a bit less
- In an article called ‘The magic number seven plus or minus two’
- If there were 12 dots on a screen and then they were covered, people could only recall 7 - same for musical notes, letters and words
Describe research that has investigated duration in STM
- Peterson and Peterson (1956) studied the duration of STM using 24 students - each tested over 8 trials
- A participant was given a consonant syllable and a three-digit number (e.g. THX 512)
- Participants had to recall the consonant syllable after a retention interval on 3, 6, 9, 12, 15 or 18 seconds
- During the retention interval, they had to count backwards from their three-digit number
- Found 90% correct over 3 seconds, 20% correct after 9 seconds and 2% after 18
Describe research that has investigated duration in LTM
- Bahrick et al. (1975) tested 400 people aged 17-74 on their memory of classmates by doing a photo recognition test with 50 photos from their yearbooks
- Also a free-recall test where participants had to list names they could remember of those in their graduating class
- Participants who were tested within 15 years of graduation were 90% accurate
- Participants tested after 48 years, 70%
- Free recall: 15 years = 60%, 48 years = 30%
Describe research that has investigated coding in STM and LTM
- Baddeley (1966a and 1966b) tested acoustically and semantically similar words
- Participants had difficulty remembering acoustically similar words in STM but not LTM
- But semantically similar words posed little problem for STMs but led to muddled LTMs
- Suggests STM is encoded acoustically and LTM is encoded semantically
What is the multi-store model of memory?
An explanation of memory based on three separate memory stores, and how information is transferred between these stores
What is the sensory register?
Information at the senses - collected by eyes, ears, nose, fingers, and so on
Retained for a very brief period by the sensory registers (we can only hold accurate images of sensory information momentarily - less than 1/2 a second)
Large capacity
Encoding method depends on the sense
Outline the multi-store model of memory
- Atkinson and Shiffrin (1968) suggested in MSM as a theoretical model of memory. It is unitary
- Consists of three memory stores
- The first store in gaining and retaining information is the sensory register, where information is held at the senses (eyes, ears, nose, fingers, tongue, etc..) | Large capacity but very short duration
- To move onto the next store (STM), you must pay attention to sensory information at the sensory register
- Information is retained in STM via maintenance rehearsal and moves onto LTM via elaborative rehearsal
- Information can be retrieved from LTM via retrieval
- Information can be lost from any of the memory stores at any time
What is the Working Memory Model?
A model of memory proposed by Baddeley and Hitch (1974) used when working on a task. Each store is qualitatively different
What are the components on the Working Memory Model?
Central Executive
Episodic Buffer
Visuo-spatial Sketchpad
Phonological Loop
Long-term Memory
What is the central executive?
Monitors and coordinates all other mental functions in working memory. Essentially - the equivalent of paying attention to
What is the episodic buffer?
Added by Baddeley in 2000 due to the realisation that the model needed a general store
Receives input from many sources, temporarily stores this information, and then integrates it in order to construct a mental episode of what is ben experienced
What is the phonological loop?
One of two slave systems in the WMM. Codes speech sounds in working memory, typically involving maintenance rehearsal (repeating the words over and over again). This is why this component of working memory is referred to as a ‘loop’.
Contains the Phonological store (inner ear) and the Articulatory process (inner voice)
What is the visuo-spatial sketchpad?
Codes visual information in terms of separate object as well as the arrangement of these objects in one’s visual field
Contains the Visual cache and Inner scribe
What is a visual cache?
Stores information about visual items (e.g. form and colour)
What is an inner scribe?
Stores the arrangement of objects in the visual field
What is the phonological store?
Holds the words you hear (inner ear)
What is an articulatory process?
Used for words that are heard or seen. These words are silently repeated/looped (inner voice)
Maintenance rehearsal