Beyond SHOUTING: What Science Really Says About ALL CAPS in Ads
All caps feel loud. That’s the point. From social feeds to supermarket shelves, marketers lean on capital letters hoping to exaggerate the point they want to make. But does this typographic shortcut actually help messages stick?
A new five-study investigation (“The effects of letter capitalization in advertising headlines”, Willemsen et al., 2024) published in the Journal of Marketing Communications finally gives us answers. By analyzing consumer reactions across thousands of real ads, researchers have mapped out the actual effects of headline capitalization on attention, processing, and recall.
Key Findings: What the Research Shows
All caps are everywhere: Over 80% of audited ads included at least one fully capitalized word—typically in the headline.
Slower reading: Audiences took longer to read headlines written in ALL CAPS compared to mixed-case versions of the same text.
Worse recall for longer lines: For headlines of 7–8 words, full caps significantly reduced recall. For shorter headlines (3–4 words), there was no meaningful difference.
No boost in brand perception: All caps didn’t affect how consumers rated the ad’s aesthetics, the brand’s premium feel, nor their attitude toward the message.
Selective caps work better: Highlighting 1–2 key words (e.g., “ORGANIC INGREDIENTS”) helped guide attention to the key message without sacrificing processing fluency.
What’s Happening in the Brain
While the temptation to “shout” in caps is strong, neuroscience tells a different story. Our brains are optimized to process mixed-case text. Specifically, the brain’s visual word-form area (VWFA) recognizes the unique contours and shapes of words more efficiently when they’re written in standard formats. Full caps flatten those shapes, making recognition less fluent—even if the message is technically readable.
Slower recognition, even by fractions of a second, can cost you attention, reduce comprehension, and lower retention. For marketers, that adds up to less effective communication.
Why It Matters
Great advertising isn’t about being louder—it’s about being relevant and brain-friendly, thus clearer, faster, and more memorable. When visual design makes processing more effortful and slower effectiveness is at risk.
Here are the key take-aways to ensure effectiveness:
Use ALL CAPS strategically – not universally.
Reserve capital letters for key terms to emphasize key concept, benefit, features or ingredient.
Keep headline length in mind: The longer the line, the greater the negative impact of ‘all caps’.
Brainsuite: maximize impact of your assets and campaigns
At Brainsuite, we help brands to implement neuroscience insights like this at scale across all assets with the power of AI.
Besides many other effectiveness KPIs, we leverage AI to detect capital letters to ensure that all assets are compliant to this success criteria across all assets.
Brainsuite is the only AI-based pre-test platform that evaluates images, videos, language and audio. And when it comes to language, we not only process formal aspects like reading time or the share of capital letters, we also predict if the text or voice-over activates emotional response, resonates with target group needs and helps build intended brand associations.
Want to make sure your message lands? 👉 Explore Brainsuite’s ad evaluation Solutions
Source
Willemsen, L. M., & Neijens, P. C. (2024). The effects of letter capitalization in advertising headlines. Journal of Marketing Communications. https://doi.org/10.1080/13527266.2024.2401393