When you work in front of a screen all day building your next great app, it's sometimes easy to forget that ultimately, all the work you're doing is in the service of real people.

Much has been written about what, universally, makes people tick: on how we see, hear, think, and feel. Here are some of the insights I've found most interesting:

See

The rapid movement of our eyes is called a saccade. There are two types: scanning and reflexive. The former is voluntary visual focus, while the latter is triggered by stimuli in your peripheral vision. Even at 10 degrees away from our point of fixation, we already lose 90% of detail (Smith and Atchison 1997). Furthermore, here, we are nearly colour-blind (Wyszecki and Stiles 1982).

So what's the best way to notify your users on some change out of the corner of their eye? Sure you could morph shapes and change colours, but quick movements at an anchored position seems to work best (Bartram, Ware, and Calvert 2001).

Hear

People love listening to stories. The linear structure from a beginning to an end, in any genre, takes the reader on an emotional journey, creating empathy and understanding on the way. Telling stories through your app or site is an amazing way to convey information in an interesting and memorable way – probably one of the reasons why long, single-page sites are so popular these days. Interestingly, people cannot help but fill the gaps in stories with their own imagination, creating bridges to causalities, even when none exist (Chabris and Simons 2010).

Think

It would seem hard to believe that cafe loyalty cards are more likely to be completed if they started off with a couple of stamps filled in, right? Turns out, it's true. A study by Nunes and Dreze published in 2006 shows that these cards were completed at double the rate of unstamped cards, and were also completed sooner. Dubbed the ‘empowered progress effect’, this is an effective method to make people think they have made progress, which pushes them towards completion.

Feel

When we're surprised (in a good way), our brain releases dopamine, a reward chemical that makes us feel good. These surprises can come in many sizes – from real rewards gained, to little messages that encourage and motivate in a playful way (eg. ‘Awesome stuff!’).

In 2001, Gregory Berns went further to show that our brains not only enjoy surprises, they crave them. In his study, water and fruit juice were squirted into participants' mouths in regular and unexpected intervals. Sure, getting a squirt of fruit juice proved more popular than water, but above all this, it's the unexpected squirts that most lit up the part of the brain associated with experiencing pleasure.

If you find these kinds of research as fascinating as I do, check out books like 100 Things Every Designer Needs to Know About People by Susan Weinschenk and Seductive Interaction Design by Stephen P. Anderson.

And while not every one of these insights lends itself to building a better app or website, every one of them helps us understand people better.