short term memory

Question 1

coding

Answer 1

Acoustically.
Baddeley tested this out by presenting participants with 2 word lists. One was acoustically similar, e.g. pat, mat, hat, and one was semantically similar, e.g. large, big, huge. Participants were better at recalling words that were semantically similar than acoustically similar. Because participants mixed up words with similar sounds, it shows that they were encoding the words by the sound of them.

Question 2

capacity

Answer 2

5-9 digits.
Demonstrated by the Serial Digit Span Study. Participants were presented with a long sequence of digits that they had to report back in the correct order. When they fail, they have reached their digit span capacity. Jacobs used this, and found a limited capacity of 5-9 digits

Question 3

duration

Answer 3

Max 30 seconds.
Tested by Peterson and Peterson. Participants were briefly presented with a list of trigrams, and then given an interference task between the first presentation of the trigram and being asked to recall it.
After 3 second delay, 90% of trigrams recalled. After 18 seconds, only 5% recalled. The upper limit duration of STM is 20-30 seconds.