Topic 2: Memory - 2.2 Studies — Edexcel GCSE Psychology
Test yourself on Topic 2: Memory - 2.2 Studies with PEARSON EDEXCEL GCSE practice questions.
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Topic 2: Memory - 2.2 Studies explained
Peterson and Peterson (1959) investigated the duration of short-term memory by preventing rehearsal.
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Participants were presented auditorily with trigrams (meaningless three-consonant syllables) and asked to count backwards in threes from a random number. This interference task prevented rehearsal. After intervals of 3, 6, 9, 12, 15, or 18 seconds, a red light signalled them to recall the trigram. Recall accuracy dropped rapidly, from high accuracy at 3 seconds to below 10% after 18 seconds, establishing STM duration as approximately 18 seconds. A strength is the highly controlled laboratory procedure, allowing cause and effect to be established. A weakness is the artificial task, meaning it lacks ecological validity.
Your focus
- Describe the aim and procedure of the study on short-term retention, noting the auditory presentation.
- Explain how the interference task prevented maintenance rehearsal and affected recall.
- Evaluate the strengths and weaknesses of the study, including its laboratory setting and artificial task.
Topic 2: Memory - 2.2 Studies exam tips
Marking Points
- Identify the aim: to test the duration of short-term memory when rehearsal is prevented.
- Describe the procedure: participants auditorily received consonant trigrams and recalled them after varying intervals while counting backwards.
- State the findings: recall accuracy decreased significantly as the time interval increased, dropping below 10% at 18 seconds.
- Explain the conclusion: short-term memory has a limited duration of up to 18 seconds if maintenance rehearsal is prevented.
- Evaluate the study: a strength is high control over extraneous variables; a weakness is the use of artificial stimuli (low ecological validity).
Examiner Tips
- 💡Ensure you can distinguish between the independent variable (time interval) and the dependent variable (correctly recalled trigrams).
- 💡Use the specific term interference task when describing why participants were asked to count backwards.
- 💡Be prepared to evaluate the study by discussing its high level of control and its low ecological validity.
Common Mistakes
- Error: Thinking the counting task was the information to be remembered. Correction: The counting task was an interference task designed solely to prevent participants from rehearsing the trigrams.
- Error: Stating the study tested the capacity of short-term memory. Correction: The study specifically tested the duration, meaning how long information lasts, not capacity, which is how much it holds.
- Error: Claiming the trigrams were presented visually. Correction: The consonant trigrams were presented auditorily to the participants.