This book cover will catch your eye | Nudge Newsletter


Isolation Effect

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Noah Kagan tested his book cover design by photoshopping the book onto shelves to see what stood out.

The green cover isn't different, but it is distinct.

In 1933, German researcher Hedwig Von Restorff¹ published a paper on memory and distinctiveness.

She gave participants long lists of letter combinations to remember (e.g. JTSW, UCSM, PLST), but among them was a single number sequence: 9125.

When participants returned after a distraction task, Hedwig found that the distinct number combo was far more memorable than any of the letter combinations.

For his 2017 book The Choice Factory, Richard Shotton and colleague Laura Weston² repeated the experiment with 500 participants.

Participants were shown a list of numbers, 15 in black and 1 in blue.

Respondents were 30 times more likely to recall the distinctive blue number.

In a follow-up, they showed participants eleven car brand logos alongside a single fast-food brand.

People were four times more likely to recall the distinct fast-food brand.

Differentiation isn't about being objectively different from everything.

It's about being distinct in your comparison set.

Or, in other words, when the world zigs, zag³.

Cheers,

Phill

¹Von Restorff, H. (1933). Über die Wirkung von Bereichsbildung im Spurenfeld. Psychologische Forschung, 18, 299–342.

²Shotton, R. (2017). The choice factory: 25 behavioural biases that influence what we buy. Harriman House.

³Hegarty, J. (2011). Hegarty on advertising: Turning intelligence into magic. Thames & Hudson.

As a behavioural science practitioner, I believe in the peak-end rule.

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