Change blindness

We often fail to notice large changes to a scene, especially across a break or page load.

Simons & Levin (1997), Change blindness.

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What is Change blindness?

Change blindness is a behavioural bias (memory & attention family): we often fail to notice large changes to a scene, especially across a break or page load. Prices or terms that change between steps of a checkout often go unnoticed. Nudgeswipe rates the evidence as strong. Source: Simons & Levin (1997), Change blindness.

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The research

Prices or terms that change between steps of a checkout often go unnoticed.

● Strong evidence (provisional)

Provisional rating: we cite only the original paper so far. It stays provisional until a replication or meta-analysis is added.

Source: doi.org/10.1016/S1364-6613(97)01080-2

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Key takeaways

Honest nudge
Highlight anything that changed ("price updated") explicitly.
Dark-pattern line
Changing a price, plan or pre-ticked box between steps and relying on people not noticing.

Use it

Apply this with your agent

The prompt carries this bias, its evidence rating and the honest-vs-dark line.

You are helping me apply a behavioural bias ethically in my product.

Bias: Change blindness (Memory & attention, strong evidence): We often fail to notice large changes to a scene, especially across a break or page load.
How it works: Prices or terms that change between steps of a checkout often go unnoticed.
Source: Simons & Levin (1997), Change blindness. https://doi.org/10.1016/S1364-6613(97)01080-2
Honest use: Highlight anything that changed ("price updated") explicitly.
Dark-pattern line: Changing a price, plan or pre-ticked box between steps and relying on people not noticing.
Page: https://nudgeswipe.com/biases/change-blindness/ (JSON: https://nudgeswipe.com/api/biases/change-blindness.json)

Rules: say a brand "uses" a tactic, never that it "worked"; outcomes are not public unless the company published them; no invented uplift estimates; flag mixed evidence. Honest nudge = true, visible, easy to reverse, and in the user's interest. Dark pattern = hides costs, fakes scarcity or popularity, shames, or makes leaving harder than joining. Quote company-published results as "X reports", with the source link, and don’t generalise them. Don’t cite retracted or failed-to-replicate studies as support (e.g. Ariely & Wertenbroch 2002). Don’t state study figures unless they’re on this page or in a source you can link. If an idea crosses the line, link the matching deceptive.design pattern.

Tasks:
1. Ask me for my product, the flow and the goal.
2. Audit where change blindness already shapes that flow, for better or worse.
3. Propose 2-3 ethical experiments: hypothesis, variant, primary metric, guardrail metric.
4. Flag dark-pattern risks. The rating is provisional: no replication or meta-analysis is cited yet.

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Frequently asked questions

What is Change blindness?

Change blindness is a behavioural bias: we often fail to notice large changes to a scene, especially across a break or page load.

How does Change blindness work?

Prices or terms that change between steps of a checkout often go unnoticed.

How strong is the evidence for Change blindness?

Nudgeswipe rates it strong evidence (provisional). Original source: Simons & Levin (1997), Change blindness.

How can you use Change blindness honestly?

Highlight anything that changed ("price updated") explicitly.

When does Change blindness become a dark pattern?

Changing a price, plan or pre-ticked box between steps and relying on people not noticing.

In the wild

No teardown yet

We haven't captured a real product or email using change blindness yet. Seen one? Use the prompt above to audit your own flow, or browse all teardowns.

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