Petersens duration experiment

Question 1

aim

Answer 1

investigate the DURATION of STM

Question 2

what type of experiment

Answer 2

LAB

Question 3

procedure

Answer 3

• 24 psy students, recalling trigrams (meaningless three-consonant syllables like TGH, CLS etc)
• presented one at a time and had to recalled them in intervals of 3,6,9,12,15
• they then had to count backwards in threes or fours from a specific random number until a red light appeared in which they had to recall the trigram (known as BROWN PETERSON TECHNIQUE)

Question 4

findings

Answer 4

3 secs- 80% recalled correctly
6 secs- 50%
18 secs- less than 10%

Question 5

conclusion

Answer 5

STM only has a duration of 18 secs

Question 6

strengths

Answer 6

high internal validity

high control of other variables

Question 7

weaknesses

Answer 7

• used artificial stimuli which doesn’t reflect real life activities
• lacks external validity