Sensory and Short Term Memory (Chapter 5)

Question 1

Modal model of memory

Answer 1

Input -> sensory memory -> short term memory -> (and backwards) long term memory
From short term memory: rehearsal (control process; keeps info active in STM), output

Question 2

Sensory memory

Answer 2

Large capacity
Short duration
Purpose: collect info, hold info, fill in the blanks

Question 3

Persistence of vision

Answer 3

Ability to connect visual input from the world amongst distractions (filling in missing sensory information)
Examples: not being aware of blinking, seeing a sparkler trail, perceiving movies as continuous motion

Question 4

Sperling’s experiment on duration of sensory memory

Answer 4

Whole report condition: flashed a matrix of letters for 50 ms (participants could see all letters, but could only remember 1 row on average)
Partial report condition: flashed matrix of letters, followed by tone cuing which row to recall (performance increased)
Delayed partial report condition: half second or full second delay prior to hearing tone (performance decreased)
Conclusion: sensory memory has large capacity, but short duration

Question 5

Echoic sensory memory

Answer 5

Auditory sensory memory: lasts about 2 seconds

Longer than iconic sensory memory (visual sensory memory)

Question 6

Short term memory

Answer 6

Capacity: 4-9 items
Duration: 15-20 seconds
Purpose: transfer “now” into LTM

Question 7

Peterson and Peterson task: measuring the duration of STM

Answer 7

Presented 3 consonants together (devoid of meaning)
As soon as 3 letters were presented, had participants count backwards by 3’s (prevent rehearsal)
The longer the duration of counting, the less the remembrance
Without rehearsal, not much is left after 20 seconds

Question 8

Factors important to duration of STM

Answer 8

Rehearsal (increases)
Forgetting/decay (decreases)
Interference (decreases; more empirically supported than decay: new memories take place of old)

Question 9

Proactive interference

Answer 9

Previous knowledge interferes with new

Question 10

Release from proactive interference

Answer 10

Performance on a specific task goes down after many trials, but when task switches, performance goes back up again

Question 11

Retroactive interference

Answer 11

New knowledge interferes with old

Question 12

Digit span experiment

Answer 12

Have people recall successively increasing lists of numbers

Most people have a digit span between 5 and 9 digits (7 plus or minus 2 rule, which applies to most items)

Question 13

Factors that influence capacity of STM

Answer 13

Defining an item (digits, consonants, words, etc.)
Chunking (grouping things together into a meaningful unit- increases STM)
Expertise (better STM when using meaningful units)

Question 14

Chase and Simon’s chess study (measuring expertise effects on STM)

Answer 14

Presented participants (chess experts and novices) with actual game positioning or random positioning of pieces and gave them 5 seconds to memorize positions 
Experts were better at placing chess pieces only when positioning was based on an actual game