MEMORY - Long And Short-term Memory

Question 1

Short term memory (STM)

Answer 1

stores and allows recall of information for a short period of time up to 30 seconds without rehearsal. Its capacity is very limited.

Question 2

Long-term memory (LTM)

Answer 2

Stores and enables individuals to recall information from a longer period. It has an unlimited capacity and information is stored for up to a lifetime.

Question 3

Duration

Answer 3

A measure of how long information can be stored for

Question 4

How do individuals commonly prolong STM?

Answer 4

Rehearse information stored in STM

Question 5

Who tested the duration of STM?

Answer 5

Peterson and Peterson (1959)

Question 6

Peterson and Peterson STM study (1959) method

Answer 6

• 24 undergraduate students were presented with a consonant trigram
• They were then asked to count backwards in 3’s from a given number
• After 3, 6, 9, 12, 15 or 18 seconds, participants were asked to repeat their given trigram
• Process repeated using different trigrams

Question 7

What were the results of the Peterson and Peterson study when looking at the duration of short-term memory?

Answer 7

• 90% of trigrams were remembered after 3 secs
• 20% of trigrams were remembered after 9 secs
• <10% of trigrams were remembered after 18 secs

Question 8

What conclusion was drawn with the results of the Peterson and Peterson study into the duration of short-term memory?

Answer 8

Information disappears very quickly when you cannot rehearse it and the maximum STM duration is about 18 seconds.

Question 9

Evaluate Peterson and Peterson’s study into the duration of short-term memory

Answer 9

• The study was a lab experiment meaning variables were tightly controlled and the procedure can be replicated to test if results are reliable by repeating the experiment on lots of participants over time to see if the duration of STM changes over time.
• The study had low ecological validity as trigrams are very unrealistic things to remember and the task as a whole was not likely to happen in everyday life therefore the findings of the experiment may not be applied to real life.
• Trigrams presented on previous trials may have caused confusion or interference when participants remembered trigrams in future trials, so it is unsure if the results were entirely representative of STM or if interference skewed the results.