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Case file

Suffix Effect

Filed under
What Should We Remember

The charge

The suffix effect is the drop in recall for the last items in an auditory list when an extra, irrelevant sound or word is added at the end. A meaningless trailing addition can wipe out the usual recency advantage.


How it operates

The final auditory items rely partly on a fragile short-lived acoustic trace. An added suffix overwrites or interferes with that trace, reducing recall of the true ending items.

Logged incidents

  1. Incident 01

    A verbal checklist is recalled less accurately when the speaker adds a casual 'okay?' after the last important item.

  2. Incident 02

    A sales rep gives final contract terms verbally, then appends a joke, causing the buyer to misremember the closing details.

  3. Incident 03

    An operations lead reads critical final steps aloud in a meeting and then tacks on unrelated chatter that blurs recall.

What to watch for

Notice whether the last spoken details become fuzzy after extra filler is added. Ask: "Did an irrelevant trailing comment interfere with what I just heard?"

Recommended action

Keep endings clean: pause after the final item, repeat the last items, and provide written confirmation. In high-stakes settings, avoid filler after key auditory instructions.

Known associates

Source of record

en.wikipedia.org

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