Expeirments

Question 1

Peterson and Peterson Aim

Answer 1

Look at the duration of short term memory

Question 2

Peterson and Peterson process

Answer 2

Lab experiment - 24 participants had to recall trigrams.
Trigrams presented one at a time
Had to be recalled after intervals of 3,6,9,12,15 or 18 for each trial
Participants had to count backwards in threes or fours from a specified random digit number until they saw a red light appear.
Known as the brown technique - prevent rehearsal.

Question 3

Peterson and Peterson results

Answer 3

Their results showed that the longer each student had to count backwards, the less well they were able to recall the trigram accurately.
- After 3 seconds 80% of the trigrams were recalled correctly.
- After 6 seconds this fell to 50%.
- After 18 seconds less than 10% of the trigrams were recalled correctly

Question 4

Peterson and Peterson evaluation

Answer 4

Used fixed timings (that Participants counted back from), also emanated background noise that could have influenced memory, so good control and no extraneous variables
- Lacked realism’s and external validity as used very artificial stimuli
- Only considers short term memory form one type of stimuli (remembering letters) could have looked at pictures or tunes…

Question 5

Miller Aim

Answer 5

Investigate the capacity of STM

Question 6

Miller Method

Answer 6

Reviewed various stduies where participants remembered lists of letters, numbers or words

Question 7

Miller results

Answer 7

Most participants could accurately remember about 7 items, give or take 2 (known as Miller’s magic number, 7±2).

Question 8

Miller Conclusion

Answer 8

Demonstrates short-term memory has limited storage capacity, reinforcing the MSM’s claim that STM can hold only a small amount of information at once.

Question 9

Miller evaluation

Answer 9

Although Miller’s (1956) theory is support by psychological research, he did not specify how large each ‘chunk’ of information could be and therefore we are unable to conclude the exact capacity of STM. Consequently, further research is required to determine the size of information ‘chunks’ to understand the exact capacity of STM.

Finally, Miller’s (1956) research into STM did not take into account other factors that affect capacity. For example, age could also affect STM and Jacobs’ (1887) research acknowledged that STM gradually improved with age.

Question 10

Bahrick aim

Answer 10

Investigated duration of LTM

Question 11

Bahrick method

Answer 11

Participants (aged 17 to 74) identified former classmates from yearbook photos and recalled their names years after leaving school.

Question 12

Bahrick results

Answer 12

Recognition remained strong (around 90%) even after 15 years, and substantial (70–80%) even after nearly 50 years.

Question 13

Bahrick Conclusion

Answer 13

Indicates long-term memory has a very large capacity and can retain information over decades, supporting MSM’s distinction of LTM as long-lasting.

Question 14

Bahrick evaluation

Answer 14

• high levels of ecological validity as the study used real life memories. In this study participants recalled real life information by matching pictures of classmates with their names. Therefore, these results reflect our memory for real-life events and can be applied to everyday human memory.
• It is unknown how many participants may have looked at the yearbook in the intervening years
• Lacks ecological validity as used 392 American university graduates