This post is written by Heather Andrew, CEO UK of Neuro-Insight.

The Warc 100 provides a fascinating cross-section of the breadth and depth of effective, creative work from around the world. This year's top five campaigns are no exception: winners of 2016's honours include campaigns that utilise a bedtime story, military codebreaking game and displays of deformed vegetables.

Different as they are, these campaigns all demonstrate how to engage audiences and inspire them to action. One of the features that they have in common is an understanding of the role of creative messaging on subconscious processes like emotional and memory response.

Recognising this, marketers are increasingly turning to neuroscience as a means of understanding campaign effectiveness, using the results to fine tune executions or to support creative decisions.

The Warc 100's top five campaigns each showcase a combination of elements that make them particularly successful from the brain's point of view. Using over ten years of experience in neuroscience research, Neuro-Insight has reviewed them to assess what seems to lie behind their success.

1. OPSM (Australia): Penny The Pirate

Australian optician OPSM's unique story book and app combination helped parents to test their children's eye-sight at home, using a bedtime story to guide them through the process. The campaign's success can be understood by how successfully its creative and media choices incorporate all the factors which stand out for the rest of the top five: narrative drive, interactive elements and a sense of personal relevance.

Perhaps the most significant of these is the interactivity of the test which OPSM has created. The brand becomes part of the interaction between parent and child, which is naturally a moment of high emotional significance. As the brand is also facilitating children's health in the process, this is likely to make a particularly strong impact on the brains of parents.

Powerful as the creative and concept both are; the campaign stands out for its ability to solve a problem with the brand itself. This link between the creative and the call to action is the real distinction of great advertising from great entertainment, and puts OPSM deservedly at the top of the list.

2. Always: #LikeAGirl

Always famously challenged the phrase 'Like A Girl' with the goal of inspiring self-confidence in girls during puberty.

Like Volvo's Live Tests, the launch ad piques a viewer's interest from the start – the first text to appear asks: 'What does it mean to do something "like a girl"?'. This sets the brain up to engage with the ad in anticipation of answering that question.

The ad's focus on human faces and actions plays very well with the brain, and helps maintain engagement through the ad. The authenticity of the people and stories on-screen further drives a strong personal and emotional impact – both of which are likely to keep memory encoding high.

Perhaps most importantly, #LikeAGirl shows Always going beyond its product and tackling a wider societal issue. This aspect of the ad is likely to resonate strongly amongst many viewers, driving a strong positive emotional response to the brand.

3. America's Navy: Project Architeuthis

Project Architeuthis was launched by America's Navy to raise interest in their cryptology division. The secret to this campaign's success was micro-targeting an entire community of online gamers, and then leveraging the brain's love of puzzles and interactive environments to engage them.

While our brains naturally like to grapple with puzzles of various kinds, for a group as devoted to them as gamers, Project Architeuthis represented an irresistible challenge. Clues were released sporadically, using highly engaging social formats to drive intrigue and suspense – these emotions are likely to have driven a high level of memory encoding and engagement throughout the game.

The campaign also engaged whole communities of gamers, not just individuals. In so doing, The Navy brought players together to solve the puzzles as a team. Even if people didn't complete the challenge, having played and interacted with the game within their social communities is likely to have driven a sense of personal relevance and commitment, contributing to positive associations about the brand.

4. Intermarché: Inglorious Fruit and Vegetables

Next up is Intermarché, a French supermarket which showcased its 'ugly' fruits and vegetables and offered them at a lower price point, tempting shoppers to opt for something less than perfect.

This campaign is different to others in the top five list as it is direct marketing – as such, the right 'nudge' factors such as the availability, display and pricing of products drive purchases. However, the concept of boldly showcasing unattractive produce in the first place is an interesting one from the brain's point of view. While the sight of deformed fruits and vegetables might be unpleasant for some audiences, advertising the cause against wastage which is behind the campaign is likely to tap into existing associations about social good, triggering positive reactions to override any aesthetic doubts.

5. Volvo: Live Test Series

Opening the top five list is Volvo's Live Test Series, a campaign designed to showcase the leading edge features of Volvo trucks. This campaign was propelled by an unlikely viral hit – the infamous 'Epic split' clip – but each part of the video series plays well to the brain.

Intrigue is central to these clips, with each one inviting a question: "What is Jean-Claude van Damme doing up there?", "Why is that man buried in a desert?", "How does the truck hang in mid-air?". From here, Volvo ensures that its product feature is the answer to each question the ad poses initially – an apparently simple mechanism but it means that Volvo's core messaging is intrinsic to the narrative of the ad and so likely to be encoded into the audience's memory. Combining a vein of excitement and humour through each clip is a great way to ensure that, as the brand is encoded into memory, a positive emotional response is attached to it.