Lecture 5 - Memory

Question 1

What is memory?

Answer 1

Processes involved in retaining, retrieving, and using information about stimuli, images, events, ideas, and skills after the original information is no longer present.

Question 2

Is memory an active or passive process?

Answer 2

Active any time some past experience has an impact on how you think or behave now or in the future.
Memory is a behaviour of neurons, not a passive storage!

Question 3

What is sensory memory?

Answer 3

initial stage that holds all incoming information for seconds or fractions of a second

Question 4

What is short term memory?

Answer 4

holds five to seven items for about 15 to 20 seconds

Question 5

What is long term memory?

Answer 5

can hold a large amount of information for years or even decades

Question 6

Describe the modal model of memory.

Answer 6

Atkinson and Shiffrin’s (1968)

Had structural features including sensory, short term and long term memory.

Question 7

What are control processes?

Answer 7

active processes that can be controlled by the person

Question 8

Describe Sperling’s study in 1960.

Answer 8

• attempted measuring the capacity and duration of sensory memory
• presented an array of letters flashing quickly on a screen

Whole report method:
- participants asked to report as many as could be seen
- average of 4.5 out of 12 letters (37.5%)

Partial report method:
- participants heard tone that told them which row of letters to report.
- average of 3.3 out of 4 letters (82%)
- participants could report any of the rows

Delayed partial report method:
- presentation of tone delayed for a fraction of a second after the letters were extinguished
- average of 1 out of 4 letters (25%)
- performance decreases rapidly

Question 9

What was the results of sperlings experiment?

Answer 9

The decrease in performance is due to the rapid decay of iconic memory (=sensory memory in the modal model).

The letters that were reported were moved from sensory memory to short term memory

Question 10

What is the duration of STM and how is it tested?

Answer 10

15-20 seconds

Tested with recalling letter and digit series tasks
Participants read aloud series of letters and/or digits
recount them backwards
After a set time (decay interval), they recall a part of the series
After 3 seconds, participants performed at 80%
After 18 seconds, participants performed at 10%

Question 11

What is proactive interference?

Answer 11

previous knowledge interferes with new information

Question 12

What is retroactive interference?

Answer 12

new information interferes with existing knowledge

Question 13

What is the capacity of STM and how is it measured?

Answer 13

Digit span task
How many digits a person can remember
Typical result: five to eight items (Magical Number 7 +/- 2)
Last 15 to 20 seconds or less

Question 14

What is chunking?

Answer 14

• small units can be combined into larger meaningful units
• very effective learning strategy & STM control process

Chunk - a collection of elements strongly associated with one another but weakly associated with elements in other chunks

Question 15

What is the change detection paradigm?

Answer 15

STM test that prevents chunking strategies via meaningful units Luck & Vogel (1997)

Memory capacity = “Amount of information” rather than number of items

Used colored squares as well as complex objects to prevent (verbal) rehearsal

Question 16

What is working memory?

Answer 16

a limited capacity system for temporary storage and manipulation of information for complex tasks such as comprehension, learning, and reasoning

Question 17

How does WM differ from STM?

Answer 17

STM holds information for a brief period of time
WM stores, processes and manipulates information, and is active during complex cognition.
Related to executive attention

Question 18

What are the two components of the phonological loop?

Answer 18

Phonological store: Limited capacity for verbal & auditory information; only holds information for few seconds.

Articulatory process: Responsible for rehearsal that keeps information from decaying.

Question 19

What is the visuospatial sketchpad?

Answer 19

Holds spatial & visual information (visual imagery) in the mind in the absence of a physical visual stimulus

Question 20

What is the central executive?

Answer 20

Focuses, divides, switches attention.
Acts as the attention controller & accesses long term memory.
Controls suppression of irrelevant information & phonological loop & visuospatial sketchpad.

Question 21

What is perseveration?

Answer 21

typical behaviour patients with damage in frontal lobe; repeatedly performing the same action or thought even if it is not achieving the desired goal
caused by damage to central executive

Question 22

How is WM capacity tested?

Answer 22

Tested with reading span task & operation span task (diagnostic tools to assess individual differences in WM)

Question 23

What are examples of interference that affects the capacity of WM?

Answer 23

Phonological similarity effect: letters or words that sound similar are confused

Articulatory suppression: speaking prevents one from rehearsing items to be remembered

Word length effect:
memory for wordlists is better for short words it takes longer to rehearse long words and to produce them during recall.

Question 24

What is the episodic buffer?

Answer 24

added when model was revised

backup store that can hold information longer and has greater capacity than phonological loop or visuospatial sketch pad
uses techniques like chunking
communicates with long-term and working memory components

Question 25

What is WM from a neural perspective?

Answer 25

behaviour of neurons (being active) while controlled attention (executive function) mediates different processes

Question 26

What does the prefrontal cortex do?

Answer 26

responsible for processing incoming visual and auditory information.
Monkeys without a prefrontal cortex have difficulty holding information in working memory.

Question 27

What are the different types of LTM?

Answer 27

Explicit (conscious) - episodic and semantic
Implicit (not conscious) - procedural, priming and classical conditioning

Question 28

What is the serial position curve?

Answer 28

Shows the distinction between short-term and long-term memories
(Murdoch 1962)

Read word list and write down all words remembered.

Question 29

What is the primacy and recency effect?

Answer 29

Memory is better for words presented at the beginning of the list (primacy effect) and at the end (recency effect).

Question 30

Describe what happened with patient HM

Answer 30

Surgery removed hippocampus

Retained short-term memory (STM) but unable to transfer info to long-term memory (LTM)

Unable to form new LTMs

Question 31

What happened to patient KF?

Answer 31

Accident damaged parietal lobe

Impaired STM (reduced digit span) but functional LTM

Able to form and hold new memories

Question 32

What does info from patient HM and KF tell us?

Answer 32

Highlights the role of hippocampus for encoding episodic information & the parietal lobe for attention & WM

Question 33

What is episodic memory?

Answer 33

Involves mental time travel

Tied to personal experience; remembering is reliving.

“Self-knowing” (re-experiencing)
E.g. Remembering standing at the Eiffel tower

Partially overlaps with autobiographic memory

Question 34

What is semantic memory?

Answer 34

Does not involve mental time travel.

General knowledge, facts
“Knowing”

E.g. Knowing Paris is the capital of France.

Often result from episodic memories