Learning Science · Retrieval, interference and forgetting
Interference between related experiences
Explain how related memories can compete and use distinctive relationships to reduce confusion.
Use the examples to connect this lesson with the earlier topics. No specialist equipment is needed.
Back to the chapterAfter reading, you can
- Distinguish proactive and retroactive interference
- Choose a discrimination practice
Two similar instructions
A learner knows an old filing rule, then learns a revised one. When working later, the old rule comes to mind first. Related experiences can compete for retrieval. Interference describes cases in which one memory makes learning or accessing another more difficult.
Proactive interference is influence from earlier learning on newer learning or recall. Retroactive interference is influence from later learning on earlier recall. These are descriptions of the direction of influence, not claims that the competing information has been permanently erased.
| Target now | Competing information | Direction |
|---|---|---|
| Use the newly learned filing rule | Earlier rule comes to mind | Proactive: earlier affects newer |
| Report the earlier rule for a history task | Newly learned rule comes to mind | Retroactive: later affects earlier |
Similarity matters
Two nearly identical labels can be confused because a shared cue activates both. An unrelated memory may not compete in the same way. Rather than simply repeating each label separately, compare their defining features and the conditions for using each.
Use accurate distinguishing cues: version date, purpose or a relevant example. Avoid relying only on colour if colour is incidental or inaccessible. The distinguishing feature should remain useful in the setting where a choice must be made.
Practise selection with feedback
Present mixed cases and ask which rule applies and why. Correct errors promptly. If the newer rule fully replaces the old one, remove obsolete instructions from the working environment while retaining necessary history separately. If both rules remain valid in different conditions, teach the condition that determines the choice.
A cue that distinguishes memories should be attached to the feature that matters. For two filing rules, a version date alone may help selection, but understanding which document type the rule covers makes the choice more robust. Revisit the contrast in fresh cases, and explain why the alternative is wrong there. This practise of discrimination is different from simply alternating two memorised answers.
Worked example
Two language forms
A learner confuses “price” and “prize”. How can contrasting sentences target the confusion more directly than a bare list?
- State the meanings: price is the amount asked or paid for something; a prize is an award. Their similar forms do not make them interchangeable.
- Use a contrast: “The price of the notebook is €4” versus “The competition prize is a notebook.” Ask which word fits each meaning and why the alternative does not.
- After feedback, return with fresh sentences after a delay. Ask for selection by meaning, not by an incidental colour or the remembered location of a word on the page.
The comparison attaches each similar form to a distinguishing meaning. It practises choosing between competitors rather than rehearsing both without a selection rule.
Try it yourself
Think through each question before opening the answer.
An old rule disrupts use of a new rule. Which direction is this?
Show the answer and reasoning
Proactive interference: earlier learning is influencing the newer target.
The disrupting information was learned first and the target rule is newer, so the direction is proactive. The term names a direction of influence, not proof that the newer rule has disappeared.
Why practise similar cases together?
Show the answer and reasoning
A reasoned comparison can train attention to the distinguishing feature, provided the learner has enough guidance and correction.
Juxtaposition can expose the feature that decides the choice. Guidance and feedback are needed so the learner practises the distinction rather than alternates guesses.
After learning a new filing rule, a learner struggles to report the earlier rule for a history exercise. Which direction of interference is being considered?
Show the answer and reasoning
Retroactive interference: later learning is influencing retrieval of the earlier target.
First identify which memory is the target. Earlier disrupting newer is proactive; newer disrupting earlier is retroactive. The direction does not establish erasure.
What to carry forward
- Related memories may compete.
- Identify the feature that distinguishes candidates.
- Practise choosing under the correct conditions.
References
Sources supporting the explanations and learning checks in this lesson.