Short Term Memory

Question 1

Being able to identify a letter would be classified as what type of visual persistence?

Answer 1

Schematic Persistence

Question 2

3 pieces of evidence for STM

Answer 2

1) Brown-Peterson distractor task
2) Waugh & Norman probe task
3) Free recall serial position curves

Question 3

Short-term memory according to the simple model

Answer 3

brief retention of verbal materials

Question 4

Critical problem w/ simple model of STM?

Answer 4

Storage + Processing Tradeoffs

->retention of verbal materials is only one of several components in working memory

Question 5

Brown Peterson Task

Answer 5

• Present consonant trigram (or other very simple item to be remembered), e.g., “DFK”
• Can be maintained indefinitely with rehearsal
• Prevent rehearsal by counting backwards by 3s (distraction task) Interferes with rehearsal
• Without rehearsal, memory is very low after 15-20 s
• This trigram would be trivial to remember under normal circumstances.

Question 6

Waugh + Norman Task

Answer 6

• Present 16 digits in sequence (too many to rehearse)
• Present probe digit
• Report digit following probe in the list
• Very similar results as last task… as # intervening items increases, report decreases. Intervening digits plotted against percentage correct, vs. looking at time in Peterson task. (Intervening items= # digits between probe item and end of list).

Question 7

Free Recall Task

Answer 7

• Present list of items
• Recall as many as possible in any order
• Recall varies with serial position (where letters are presented)
• Get both primacy and recency effect

Question 8

In the free recall task, the recency effect is due to _________.

Answer 8

rehearsal

->if have to recall in order (serial recall), or prevent rehearsal, don’t see this effect as much

Question 9

4 properties of STM?

Answer 9

• Small number of items (7±2)
• Maintained with rehearsal
• Phonological representation (harder to rehearse things that sound alike)
• Rehearsal leads to long-term retention

Question 10

Waugh + Normal Model of STM

Answer 10

• Input-> STM, where you can rehearse (loop) to keep available in STM. With each rehearsal, is some probability of moving into long term storage…some prob of->LTM
• a part of the modal model of cognition and memory

Question 11

4 problems with the Waugh +Normal model of STM

Answer 11

1. Visual info seems separate (dual task phenomena)
2. Simulations of processing require more temporary storage, typically not rehearsed
3. Rehearsal neither necessary nor sufficient for LTM
4. Background for different conception of STM retention, working memory

Question 12

3 levels (types of processing)?

Answer 12

Graphemic (how many es), phonological(does it rhyme w/..?), or semantic processing (to do w/ meaning)

Question 13

In an unexpected incidental recall task, ________ processed items are retained much better.

Answer 13

Semantically

(Graphemic < Phonological <Semantic), shows rehearsal not necessary for LT retention

Question 14

2 types of storage/ processing tradeoffs?

Answer 14

Memory load & semantic verification

Memory load & reasoning

Question 15

Semantic verification & memory load

Answer 15

verification time of something semantic (like do canaries have gills?) increases with memory load (number of digits to remember)

Question 16

Memory load & reasoning

Answer 16

• Verification time of simple T/F judgements of logic increases w/ M. load (digit #)
• > Interpretation: Even simple tasks need WM space to be done efficiently

Question 17

Storage and processing may be

Answer 17

interdependent