When something piques our curiosity, our minds take a few moments (about 6 seconds) to make sense of it and potentially store its meaning in long-term memory. Whilst we are busy doing this, we don't have much mental capacity left to process experiences that occur immediately afterwards. The best film and ad makers understand and allow for this by providing a few seconds' down time between the important moments. Ads without these breathing spaces make it difficult for viewers to remember anything whereas the best ads have a rhythm that allows people to remember what's important. A 30 second video ad, for example, should have about 4-5 peaks of attention that between them capture the brand and the meaning viewers need to be left with.
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