Duration of Memory Flashcards
What does the term duration refer to?
Duration refers to the amount of time information can be held for
What two psychologists conducted research into the duration of memory? Which psychologist conducted research into the short term memory? long term memory?
Bahrick et al - long term memory
Peterson and Peterson - short term memory
Outline the experiment conducted by Peterson and Peterson
In the experiment, the participants were given “nonsense trigrams” and a three digit number to remember. They were then asked to recall the nonsense trigram after a retention interval had passed, ranging from 3 -18 seconds. During the retention interval, the participants had to count backwards from their three digit number
What is a nonsense trigram?
Three random letters that have no known abbreviation or acronym
What was the idea behind having participants counting backwards from the three digit number given?
The idea was to stop participants from rehearsing the nonsense trigram and allow psychologists to measure the duration of memory without any confounding variables
What was the conclusion of Peterson and Peterson’s study?
Peterson and Peterson concluded the short term memory’s duration was 18-30 seconds long
What were the findings of Peterson and Peterson’s study?
They found that after 3 seconds, 80% of participants could correctly recall their nonsense trigrams. After 18 seconds, fewer than 10% could correctly recall their nonsense trigrams. Therefore, recall got progressively worse as the delay grew longer
What were the findings of Bahrick et al’s study?
In the photo recognition task, people were 90% accurate if they had graduated in the last 15 years. Numbers dropped to 70%, if they had graduated in the last 48 years.
In the free recall task, numbers were lower. There was a 60% accuracy if graduated in the last 15yrs and 30% accuracy if graduated in the last 48 years.
This suggests that the long term memory can potentially last a lifetime
Outline the study by Bahrick et al
Bahrick et al had 392 participants, all aged 17-74 years old. Thei ability to recall was tested using year books. There were two tasks performed by the participants, which were a photo recognition task and a free recall task
How many evaluation points are there?
There are two evaluation points
What is a strength of Bahrick et al’s study?
Bahrick’s study is high in external validity. This is because the researchers investigated meaningful memories; for example - peoples’ names and faces. When other research has been conducted with meaningless pictures, recall rates have been lower. This suggest that Bahrick et al’s findings reflect a more real estimate of the duration of long term memory
What is a limitation of Peterson and Peterson’s study?
Peterson and Peterson’s study has artificial stimuli. Although it is not completely irrelevant as we do sometimes try to remember fairly meaningless material, for example postcodes. Recalling trigrams does not reflect most everyday memory activities where what wea re trying to remember is meaningful. This means the study lacks ecological validity as it may not be generalisable to real life.
Describe one way in which psychologists have investigated the duration of short-term memory. In your answer, you should include details of stimulus materials used, what participants were asked to do and how duration was measured.
Peterson and Peterson investigated the duration of short term memory. Peterson and Peterson allocated each participant with nonsense trigrams and a random three digit number. The participants were then given a retention interval between 3-18 seconds, during which they had to count backwards from their allocated three digit number. After the retention interval had passed they were asked to recall their nonsense trigram correctly.
