Lecture 6: STS Evidence Revisited and Working Memory Flashcards
What is the duration of STS?
15-20 seconds if not rehearsed
What is encoding like in STS?
- Select from sensory memory
- Retrieve from LTS
- Reduction & Elaboration encoding
What type of code is used in STS?
A.V.L. (acoustic-verbal-linguistic)
What is the capacity of STS?
7 +/- 2 chunks of information
How does evidence with amnesic patients illustrate the existence of separate memory systems?
- “Amnesics can learn” (e.g., Puzzle WM task, teach them how to do it and they can learn. Bring them back a week later, they won’t remember learning the puzzle or meeting you but they can solve the puzzle [shows that something is getting into LTM]. Pricking them with a pin when shaking their hand, a couple weeks later they remember the aversive event [pulled away before shaking Chris’ hand]. They don’t remember you or the event but seem to remember the pin)
How did the study by Kroll et al. (1970) illustrate that coding in STS is more than just AVL?
- Visual codes in STS
- Task: shadowing + test letter (auditory vs. visual presentation)
- Retention interval 1 to 15 sec (during which time they are shadowing)
- Recall test letter
- Results: short interval recall 96%, auditory = visual and long interval: recall visual > recall auditory
- At the longer interval, the performance on visual recall was greater than auditory recall because there was no space for more audio information because they were shadowing. Suggests that the code that was used to keep that visually presented letter was different than the code that was used to keep the auditory presented letter.
- Note: Suggests visual code of test letter (presented
visually) can be maintained in STS.
How did Shulman (1971) show evidence for semantic code in STS?
- Evidence for semantic code in STS
- Task:
- List of ten words (500 ms each)
- Probe word: does it match an item from list?
- Probe type: related (boat/ship) vs. unrelated (e.g., boat / shin)
- Results: false positives when related (thinking a word like ship was on the list because it was connected to boat)
- Suggests: information in STS may include semantic code
What was the original STS/LTS distinction based on and what has been extended?
- Amnesic evidence (has been extended, people with Amnesia can learn and transfer things to LTM even though they suffered extensive damage that would prevent this)
- Code (has been extended; people can be encouraged to use a different. Generally gravitate towards using an AVL code unless otherwise inclined by the task or their abilities)
- Duration (has not been extended, still 15s without rehearsal)
- Capacity (Has not been extended, still 7+/- 2
How did Baddeley describe STS vs. Working memory?
STS: - initially viewed as a storage system - however, the same system seems to be important for active processing and manipulation of information - a new concept needed to extend STS WM: - active system for temporary store & manipulation of information
What are the components of working memory?
- central executive
- phonological loop
- visuospatial sketchpad
What is the central executive component of working memory?
- plan actions (conscious thinking), integrate information, initiate control (over what happens next, i.e., the boss or executive)/decisions
- transfer of info. to/from LTS
- rehearsal, recoding (e.g., from auditory code to visual code)
What is the phonological loop component of working memory?
- recycle information for immediate recall. Responsible for storage & rehearsal of verbal information, & phonological processing
- two parts: Phonological storage/store (passive, will fade away after 15 secs unless you reactivate them) and articulatory rehearsal (active processing)
What is the visuospatial sketchpad?
- Deals with visual and spatial (locating where things are in space) information
- visual imagery tasks
- spatial visual search tasks
- Two parts: visual cache (storage, stays for a short period of time) and inner scribe (processing)
How can arithmetic be used as an example of working memory?
- (4+5) x 2 / 3+ (12/4)
- CE - retrieves rules of computation from LTS and retrieves facts from LTS to solve: (4+5) = 9, x 2 = 18
- PL - temp stores “18”
- CE - retrieves rules and facts from LTS to solve: (12/4)=3, 3 + 3 = 6
- PL - temp store “6”
- CE - retrieves rules, retrieves items from PL to compute: 18 / 6 = 3
What are the 3 general assumptions of Working memory?
- There is only one WM System and it operates on many tasks (math, reading,
driving) - WM has a limited storage and processing capacity
- Demands of task #1 can limit performance on task #2
What are the assumptions regarding the two subsystems?
- Involve simple low-level processing
- rehearsal / maintenance of information - Subsystems are domain specific
- phonological vs. visuospatial - Each subsystem has own limited (small) pool of
attentional resources
- may also drain (rely on) resources from the CE
What is the phonological store?
- passive store that holds verbal information
- forgotten unless rehearsed & refreshed
What is the articulatory loop?
- active refreshing of verbal information
What is the articulatory suppression effect?
- memory for words poorer when concurrently try to
say something responsible for storage & rehearsal - “act of speaking” uses up resources in the
articulatory loop à so words from list cannot be
refreshed and are lost - Real world effect – it’s hard to read while in room
with other people talking
What is the phonological similarity effect?
- memory poor when try to remember words that are
similar - “boat, bowl, bone , bore” harder than “stick, pear,
friend, cake” - why? Similar sound codes get confused in the
phonological store
What is the focus generally on when discussing the phonological loop? what evidence is there for other codes?
- focus is generally on verbal aspects of phonological loop, but also some evidence for other codes:
- Musical pitch: find get confused by similar pitches just like the phonological similarity effect
- Nonverbal communication like ASL
How did the study on ASL demonstrate the existence of other codes?
- congenitally deaf, skilled at ASL
- presented word lists written or in ASL sign:
- word lists were either phonological similar (shoe,
through, new) or cherologically similar (hand
movements) - found memory confusions based on cherological
relatedness! - deaf people coded (& recoded) in ASL, & used ASL
code in phonological loop
What evidence exists for the visuospatial sketchpad?
- Evidence: mental rotation (of 3D objects)
- people shown first figure and must indicate whether second figure is same or different (the second figure has been rotated)
- requires mental rotation
- Picture plane (e.g., left to right; first shape in panel A), depth plane (e.g., back to front; first shape in B panel)
- results: mental (image) rotation can be done. Time to decide same/different varies with how far need to be rotated. The farther people had to mentally rotate the image (i.e., degree of rotation 20 degrees, 60 degrees et.), the more time it took to decide if it was the shape (i.e., linear relationship)
- visual codes can be/ are used to temporarily store
and manipulate information in STS
What is the focus of dual task method?
Focus is on evidence showing separate phonological
loop vs. visuo-spatial sketchpad subsystems