Short Term + Working Memory (ch. 6)

What can we find in "memory"?

- structures (called "stores") that hold knowledge

- processes that operate on knowledge

- may also refer to the knowledge itself

Structural features of the Modal Model of memory

Sensory store, short-term store (STS), long-term store (LTS)

The Modal Model of memory views our mind as if its a BLANK

Computer

What is the capacity of the short-term store, according to a research study from 2001?

Four +/- 1

What is the duration of the sensory store?

Iconic memory lasts approximately 200-400 ms, while echoic memory lasts about 2-4 seconds

Iconic memory

A momentary sensory memory of visual stimuli, lasting for 200-400ms

Measured using a visual delay task

Echoic memory

A momentary sensory memory of auditory stimuli, lasting for 2-4s

Measured using the three-eared-person task

Rehearsal

Repeating information to help transfer it from STS to LTS

What is the Brown-Peterson task used for?

It is used to study the duration of short-term memory and assess whether forgetting is due to decay or interference

Decay

Fading of memory over time

Control processes in the Modal Model

Strategies a person uses to remember information

Includes: rehearsal, coding, and retrieval strategies

Coding in the Modal Model

Associating to-be-remembered information with already known information

Eg) using visual images to remember verbal information

Retrieval strategies in the Modal Model

Help focus on to-be-remembered information

Eg) remembering provincial capitals by starting with the west coast and working eastward

What are the pros/cons of the Modal Model?

Pros?

- division of memory is clear + intuitive

- helped guide memory research

Cons?

- oversimplified

- overstated the role of rehearsal in remembering

What did George Miller discover about STS capacity?

He proposed 'The Magical Number Seven, Plus or Minus Two' as the limit for STS capacity

Ie) we can hold 7 items in our memory, +/- 2

Digit span test

Memory test in which a series of numbers is read to subjects in the experiment who are then asked to recall the numbers in order

Used to measure STS capacity

Memory span test

Broad type of test that measures how much information someone can hold and repeat immediately in short-term or working memory

Used to measure STS capacity

Chunk

Unit of the STS

Well-learned unit of components, representing consistent or meaningful pattern

What is the significance of the Chase & Simon (1973) study?

It showed that expertise in a domain enhances the ability to recall patterns, indicating that experts have better domain-specific memories

Eg) expert chess players have a better domain-specific memories of the chess board

Can the STS be trained?

Yes, the STS can be trained to handle more information/items with lots of practice

How does chunking help with memory?

Chunking combines smaller units of information into larger, meaningful units, reducing the total amount to remember

Eg) Acronyms

What was the conclusion of the Waugh & Norman (1965) study?

The study concluded that interference, not decay, is the primary cause of forgetting in short-term memory

How'd they test this? Participants saw 16 digits and had to report the digit that followed the probe digit the first time it appeared... slower vs. faster presentation rates were compared

What did Peterson & Peterson (1959) conclude about STS duration?

STS decays in less than 20 seconds without active rehearsal

How'd they test this? Asked participants to remember 3 constantants + 3 digit number, then had them could backwards by threes + recall the number after some time

Proactive interference

Occurs when previously learned information makes it harder to remember new information

Retroactive interference

Occurs when new information replaces older information

What was the main finding of Barnes & Underwood (1959) regarding memory recall?

Recall of the original A-B list (eg, chair-dog) was interfered with by learning a new A-C list (eg, chair-tree), demonstrating retroactive interference

What phenomenon was observed in Wickens, Born & Allen (1963) when participants switched categories?

Release from proactive interference

Ie) Participants showed improved recall when the final trial involved words from a different category

What is the phonological similarity effect as demonstrated by Conrad (1964)?

Participants made more errors with similar-sounding letters than with visually similar letters, indicating acoustic coding in STM

Word length effect

Memory for shorter words is better than for longer words, as it takes less time to articulate them (say them out loud)

Articulatory suppression

Repeating a word during retention interferes with memory

Eg) Repeating the word "the" while trying to remember other items

What did Posner & Keele (1967) find about visual coding in short-term storage?

Participants took longer to decide if letters were the same name but different form, indicating that visual coding is used in short-term storage

Which tasks tend to show interference effects? Which don't?

Tasks that use the same type of processing (e.g., pointing + imagery, both visuospatial) interfere with each other more

Tasks that use different types of processing (e.g., speaking + pointing) interfere less because they rely on separate systems

What is the relationship between working memory and the brain?

Working memory is associated with specific brain regions involved in processing and storing information temporarily

What are the main components of Baddeley's working memory model?

- phonological loop

- visuospatial sketchpad

- central executive

- episodic buffer

Phonological loop in WM

Includes two parts:

1. Phonological store -> passively stores speech sounds

2. Articulatory rehearsal process -> actively processes items to prevent decay

Visuospatial sketchpad in WM

Includes:

- Visual cache -> stores form/colour info

- Inner scribe -> handles spatial/movement info, rehearses visual info, transfers info in visual cache to central executive

Inner scribe

- handles spatial/movement info

- rehearses visual info

- transfers info in visual cache to central executive

Central executive in WM

- Controls attention

- Coordinates other components

- Allows for time sharing

- Transfers information to and from long-term memory

Episodic buffer in WM

Interfaces with episodic long-term memory and integrates information into a single complex structure/experience

What did Smith & Jonides (1997) discover about working memory and brain activation?

Different brain regions are activated for verbal (left hemisphere) and spatial (right hemisphere) memory tasks, supporting the double-dissociation evidence.

What is the difference between fluid and crystallized systems in memory?

Fluid systems involve attention and temporary storage, while crystallized systems accumulate long-term knowledge

What happens when two tasks use the same component in working memory?

They cannot be performed successfully together due to limited capacity

What are the pros/cons of the Working Memory Model?

Pros?

- Conceptualizes active processing and transient storage of information

- Can be applied to complex tasks

Cons?

- role of central executive is vague

- it is unclear how components interact

What did Smith & Jonides (1997) demonstrate about working memory and the brain?

- PET scans showed that verbal working memory mainly activates left hemisphere regions, while spatial working memory mainly activates right hemisphere regions

- This supports separate systems for verbal and spatial information (double dissociation)

According to Smith & Jonides (1997), how is memory load/storage related to the brain?

- As memory load increases, corresponding brain regions showed increase in activity

- Passive storage tends to be located in the back of the brain

- Active processing tends to be in the frontal lobes