Surprise can seem kind of juvenile — something we don't really think about much once we're grown up. Surprise parties, unexpected gifts and unplanned trips to the ice-cream parlor are all mostly enjoyed by kids. But Tania Luna and Leann Renniger think we could all use more of it in our lives — and they make a pretty convincing case in their book "Surprise: Embrace the Unpredictable and Engineer the Unexpected."

They start by looking at the neurobiology and psychology behind what makes a surprise happen: Basically, the human brain is a prediction machine. "Whenever we aren't surprised, it's because we've managed to predict what would happen in the next instant with relative accuracy," Luna and Renninger write in their book. Throughout our lives, as we learn more and grow older, we generally become less easy to surprise because we've seen so much before. This explains why it's so easy to surprise babies and small children, and why surprise's sunny offspring — delight — is more accessible when traveling to a new place, trying a new cuisine or discovering something new.

Is surprise more than just a neurobiological response to new stimuli? Definitely — it's also an emotional state that has several steps. Here's how Luna and Renniger define surprise: "Surprise is an event or observation that is either unexpected (I didn't see that coming!) or misexpected (That's not what I thought was going to happen.) In either case, it is a strong neural response that shouts, 'You were wrong!' Regardless of whether the surprise is neutral, pleasant or unpleasant, all surprises trigger the same prehistoric sequence in our modern brains."

A natural inlet of Clear Lake. I was surprised (and delighted) by the intense natural colors of an inlet in Oregon's Clear Lake. I hadn't been expecting such a sight during my hike, and I didn't see it coming; the inlet appeared around a bend in the trail. (Photo: Starre Vartan)

But what if I don't like surprises?

Some people love surprises (I tend to seek them out by putting myself in new situations), but for many that's not the case. If the idea of surprise evinces a feeling of dread in the pit of your stomach, you aren't alone. A former control freak, now chief-surprisologist Luna used to feel the same way. But when she looked at her predictable, safe, secure life, she realized that while she might be comfortable, she wasn't happy. As she says in the video below, "We feel most comfortable when things are certain, but we feel most alive when they’re not."

Luna accepted the idea that surprises would take her out of her comfort zone sometimes — but it was worth it, because the rewards were that significant. In their research she and Renninger found an element of surprise intensifies emotions by 400 percent. (Now you know why marriage proposals are often formatted as unexpected events.)

Surprises have also been shown to deepen and brighten our relationships with each other, and often our clearest memories contain an element of surprise. While surprise in itself isn't inherently a good or bad emotion (of course there can be horrible surprises too), it amplifies any feeling, which is why it's often associated with intense anger, terrible shocks of sadness, the most hilarious laughs and our best happy memories.

Luna suggests we all bring more positive surprise into our lives. But how can we surprise ourselves? Well, it's more about putting ourselves in a position or opening ourselves up to new ideas. As she says in the video above, "To be a surprisologist is to look at any moment that is dull, lonely, frustrating, or unfulfilling, and say to yourself, 'What can I do that's surprising?'"

More concrete guidelines from the book and the video include:

1. Create pattern interrupts. Whatever your usual way of doing something is, try another way. Drive another way to work (or ride your bike instead!) Do you make the same four or five meals for dinner every week? Try a new recipe, or order a new type of food you've never had and have a floor picnic.

2. Seek awe. "Surround yourself with experiences that make you feel like part of something larger (nature, intricate design, extraordinary skill, admirable moral acts). Awe slows down our perception of time and makes us more helpful," write Luna and Renninger.

3. Seek novelty. "Trying new things or looking at familiar things in new ways actually elevates mood, enhances creativity and even enhances weight loss," says Luna. Novelty bumps up your natural dopamine production, the neurochemical that's associated with the excitement of new things.

4. Take positive risks. Apply to a job you think you can't get, tweet at your favorite celebrity or go for a swim in the nearest body of water (even if it's cold). Trying something creative that you don't know how to do can be a fun, low-stress way to surprise yourself. Buy a canvas and some paintbrushes and have a go at painting, try to take 10 interesting pictures a day for a week or impulsively sign up for a ceramics class.

5. Surprise others. Bringing something unexpected (how about a weirdly flavored cupcake or a carnivorous plant?) to a loved one or friend can be exciting for you (and who knows how they'll respond!) What other kinds of creative surprises could you come up with?

And if you want to be surprised, sign up for Luna's "The Experiment." You fill out a questionnaire about your personality and other things, and then you'll get a surprise. Maybe right away, maybe years from now. "The surprise may be an anonymous letter, an invitation to a secret location, or anything in between. It might arrive tomorrow, 12 years from now, or never, but if you don’t sign up, you’ll never know."

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

How to enrich your life with surprise
Embracing the unpredictable can help you lead a happier and more memorable life.