Short term memory store

Short term memory is a

temporary store

Which memory store is temporary?

Short term

What is the duration of short term memory store?

18-30 seconds

Which memory store has a duration of 18-30 seconds?

STM

Who discovered the duration of STM?

Peterson + Peterson (1959)

What is maintenance rehearsal?

Repeating information to hold it in STM for longer

If done for long enough, info can pass onto LTM

How can info be held in STM for longer?

Maintenance rehearsal

What is the capacity of STM?

Limited capacity

7 +-2 items

Which memory store has a limited capacity of 7+-2 items?

STM

Who discovered the capacity of STM?

Miller (1956)

How can the capacity of STM be increased?

Through chunking

How is STM encoded?

Mainly acoustic

What is the main way STM is encoded?

Acoustic

Which memory store mostly encodes acoustically?

STM

Who discovered how STM is encoded?

Baddeley (1966)

Peterson + Peterson (1959) method

24 undergraduates take part in 8 trials

Each trial student given a consonant syllable and 3 digit number to remember

Student counts backwards from number until told to stop (prevents maintenance rehearsal)

Told to stop after different amounts of time on each trial (called retention interval)

How did Peterson + Peterson (1959) prevent maintenance rehearsal?

Made Ps count backwards from their 3 digit number

What is retention interval?

Amount of time Ps counted until told to stop in Peterson + Peterson (1959)

Peterson + Peterson (1959) findings

% of correct responses decreased as retention interval increased

STM v. short duration

What did Jacobs (1887) test?

People's digit span

Jacobs (1887) method

Ps asked to recall 4 digit number in correct order out loud

Add 1 digit every time they get it correct until P gets it wrong

This is their digit span

Jacobs (1887) findings

Mean digit span: 9.3

Mean letter span: 7.3

What did Jacobs (1887) find is the mean for digit span?

9.3

What did Jacobs (1887) find is the mean for letter span?

7.3

What did Miller (1956) test?

STM capacity + chunking

Miller (1956) method

Made observations of everyday practices

Noticed things come in 7s like 7 days of the week

People can recall 5 words as well as 5 letters coz of chunking

Miller (1956) findings

Chunking helps people remember things

Capacity of STM is 7+-2