Memory Interference Experiment
Why do we forget? Sometimes the problem is not that a memory is gone, but that other memories are in the way. This word-list task demonstrates proactive and retroactive interference, two classic causes of forgetting.
Frequently Asked Questions
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What is the difference between proactive and retroactive interference?
Proactive interference happens when OLD information disrupts the learning or recall of NEW information — for example, an earlier word list blocking the target list. Retroactive interference happens when NEW information disrupts the recall of OLD information — for example, a second list studied after the target list blocking the target. The simplest way to remember it: proactive = old blocks new; retroactive = new blocks old.
Why is the distractor math task included?
The short math task fills your working memory so you cannot silently rehearse the words during the delay. Without a distractor, you might keep repeating the list mentally, which would mask the interference effects. The math answers are never scored — they exist only to occupy your attention.
Is this experiment a diagnostic test of my memory?
No. This is an educational demonstration of classic interference effects, not a diagnostic tool. Each condition runs only once, so scores are influenced by attention, tiredness, and practice. It is a simplified adaptation of the AB-AC paradigm used in research, not a clinical assessment.
How can I reduce interference in real life?
Space out similar learning, avoid studying similar material back to back, and get enough sleep so memories can consolidate. When two sets of material are similar, add distinctive cues (contexts, colors, or mnemonics) to help your brain tell them apart during retrieval.
Show Details
What is Memory Interference?
Interference theory argues that forgetting often happens not because a memory decays, but because other information competes with it. When similar memories overlap, retrieval becomes harder. This experiment is a simplified adaptation of the classic AB-AC paradigm: you learn a target list, and a second list either comes before it (proactive interference) or after it (retroactive interference).
Proactive Interference
Proactive interference happens when old information disrupts the learning or retrieval of new information. In this experiment, studying a prior word list before the target list makes the target harder to recall, because the earlier list competes for retrieval. It is why learning a new password or a new phone number right after an old one can feel so difficult.
Retroactive Interference
Retroactive interference happens when new information disrupts the retrieval of older information. In this experiment, studying a second list after the target list makes the target harder to recall. This is why revising material before a test is often better than cramming after: newly learned material can overwrite or compete with what came before it.
References
- Underwood, B. J. (1957). Interference and forgetting. Psychological Review, 64(1), 49-60. 10.1037/h0044616
- McGeoch, J. A. (1932). Forgetting and the law of disuse. Psychological Review, 39(6), 458-472.
- Keppel, G., & Underwood, B. J. (1962). Proactive inhibition in short-term retention of single items. Journal of Verbal Learning and Verbal Behavior, 1(3), 153-161.
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About This Experiment
This experiment is an educational adaptation for demonstration purposes. It is not a clinical diagnostic tool. Results reflect your performance in this specific session and should not be interpreted as an assessment of your cognitive abilities.
Data Privacy
Your experiment data is processed and stored locally in your browser. No data is uploaded to any server unless you explicitly export it.
