Lecture 5: Short Term Store Flashcards
1
Q
Who was Jimmie G?
A
- He was a korsakoff patient who showed the same symptoms as HM, but for a different reason.
- Was born in 1926, diagnosed as a Korsakoff patient (i.e., suffered neuronal damage because of a lack of nutrition and excessive alcohol intake. Damage to the hypothalamus and neurons within it. Cant form new memories)
- In the navy
- In 1971 he showed up at a hospital and was disoriented. He had cirrhosis of the liver and sent to a nursing facility.
- Went back to hospital and met Oliver sacks. Sacks noticed that his short term memory was good, he was good at STM tasks. His past was his high school years and his present was the navy (which had ended many years earlier)
- Sacks asked him how old he was and he said 19 and then he told him to look in the mirror which lead to confusion because he saw an old man.
- Evidence that different memory stores exist
2
Q
How do we differentiate between the different stores?
A
- Encoding
- Duration
- Capacity
- Type of code (s)
3
Q
How is information encoded in STS?
A
- Selective Attention
- select information from sensory memory
- Retrieve from Long Term Store
4
Q
What is the Brown-Peterson task?
A
Phase 1: Present just 1 CCC (e.g., MHD) - delay (0-15s) - recall - Results: 100% recall. People rehearse the CCC Phase 2: present 1 CCC (consonant, consonant, consonant) (e.g., MHD). - Delay of 0-15 s with intervening task -- Count backwards by 3 -- Rate of twice per sec. -- This prevents rehearsal of CCC - Then recall the CCC
5
Q
What were the results of phase 2 of the Brown-Peterson task?
A
- Short delay people do well but as you extend that delay while preventing rehearsal, the item starts to fade away, and after about 15 seconds performance is very low
- Suggests: decay of CCC memory trace in STS if prevent rehearsal. STS memory trace last about 15s.
6
Q
What type of coding is used in sensory memory?
A
- Basic features
- Not semantic
- Not linguistic
7
Q
What type of coding is used in long term memory?
A
- List of words (e.g., 30 words), recall hours/days later
- (people can accurately recall some of these words but then they will stop. They will be prompted to try harder to remember, then they will guess and the guessing part is interesting because when people guess in LTM tasks they give you items that are semantically connected to items in the list)
- Intrusion errors usually semantic (e.g., ship for boat)
- Suggests that LTM uses semantic code, memories based on meaning
8
Q
What type of coding is used in short term memory?
A
Intrusion errors are usually acoustic!
- Wecklegren (1965)
- List of letters aurally
- Substitution errors (i.e., guessing) were acoustic (i.e., sound-based)
- E.g., target is “T” but report “D” (sound-based errors because they were acoustically similar)
- Conrad (1964)
- Auditory and visual presentation
- Found same type of errors: “B” for “V” (even though they heard and saw the letter, they still made an auditory error B for V rather than a visual error U for V. Suggests sound based coding)
- Do not substitute “U” for “V” even though is visually more similar
9
Q
What is the name of the type of code associated with STS?
A
- Atkinson & Shriffin
- Acoustic verbal linguistic code (AKA acoustic articulatory code)
10
Q
What is capacity like in SM, LTS and STS?
A
- SM very large
- LTS very large
- STS (class online DEMO)
- limited to about 7 +/- 2
- immediate memory span
- However, there are things we can do to functionally make short term memory bigger
11
Q
What can people do to make short term memory bigger?
A
- 0110011011101010111 (recall 7 +/- 2)
- Train: 000 = 0 (e.g., 001=1)
- Results can recall about 21 0’s and 1’s!
- Could still only remember 7 +/- 2 of those chunks but functionally they are remembering a lot more because there are many numbers within each chunk
12
Q
What did de groot find in his study about master vs. novice chess players?
A
- Master vs. novice chess players
- Random vs. real game
- 5s view- delay - place pieces
- Results:
- Random condition: Masters = novice (equal STS capacities. Doesn’t matter whether you were novice or master could replace approx. the same number of pieces back on the board)
- Real game: Masters > novices (chunking- master players were able to accurately replace the pieces on the chess board whereas novices did not do well. To novice players, real games are random. Master players were able to quickly encode information into STM, chunk it into patterns, store it and then reactivate those patterns on the board)
- A type of chunking that is associated with expertise, recognized patterns
13
Q
What is reduction encoding?
A
chunking (i.e., reducing the number of items by making them into larger chunks)
14
Q
What is elaboration encoding?
A
adding to input (i.e., have information come in and you elaborate on it, put things together into integrated units you might add something to it.)
15
Q
What is the serial position curve? What did the class demo illustrate?
A
- The last part of the curve is called the recency. We are able to remember and report back the most recent items we heard in this task. Still present and active (due to rehearsal) in STM when asked to recall (when cued).
- The first part is called primacy. These items get lots of rehearsal cycles (active in STM), they and the opportunity to be transferred into LTM.
- The middle items do not get very much rehearsal and thus little transfer to LTS, so performance drops off in the middle.
- What happens when he said “oh I’ve made a mistake, wrong list” he distracted us to get us to stop rehearsing. In the second graph we get the primacy effect, we do poorly on the middle and we also do poorly on the recency effect (no recovery at the end)
- this is a robust finding, it is very replicable
