Italics are subtler than bold for emphasis
We have confirmed the functions of the widespread approach of highlighting text with italics and using bold in headlines.

This study looked at the effect of weight, width, contrast and italics in combination with the regular style.

Previous studies have found a ‘regularity effect’, in that readers have a faster reaction time if the stimulus is presented in the same font throughout than when it is presented in a mix of different styles.

The objective was to determine which stylistic features might produce a regularity effect and, further, to explore whether the incidence and extent of the effect are dependent on the nature of the visual and perceptual differences between the fonts.

While the previously described experiments with font tuning and the regularity effect compared different typefaces or highly unusual typefaces, this investigation dealt with fonts that can be described as a typeface family. This is similar to a layout situation, where designers mix regular styles, bold styles and italics.

In three experiments we investigated whether there was a regularity effect in words using a set of fonts that vary systematically from a regular weight test font. We used Rapid Serial Visual Presentation (RSVP), where a string of letters are displayed on a screen, presented sequentially in the same position. The task in this mode was to determine whether the stimulus was a word or non-word.

The findings suggested the following and thus lent support to what is a common approach among graphic designers.

Words presented in a regular style are a good basis for efficient letter recognition, while expanded fonts hamper legibility.

Setting words in italics serves to distinguish text elements without significantly disrupting reading and is therefore suitable for use in continuous text.

Bold is more appropriate than italics for headings by making words stand out.

For more see:
Dyson, M. & Beier, S. (2016) ’Investigating typographic differentiation: Italics are more subtle than bold for emphasis’, Information Design Journal, 22(1), 3-18.


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Centre for Visibility Design
The Royal Danish Academy of Fine Arts,
Schools of Architecture, Design and Conservation
School of Design

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