Need to get creative? Begin by improving your mood. That's the surprising message from bestselling author and performance expert Steven Kotler. In an excerpt from his new book The Art of Impossible, Kotler describes a fascinating experiment where a neuroscientist and psychologist teamed up to find out what happens in the brain during moments of inspiration--"aha moments." What they learned can help you when you need a burst of creativity of your own.

The researchers began by trying to induce aha moments in subjects by giving them remote association problems, also called "insight problems." In this case, the problems were a series of puzzles in which subjects were given three words and asked to find a fourth that could be combined with all of them. For example, what common word can be combined with "pine," "crab," and "sauce"? The answer is "apple."

How to have an aha moment.

Some people solved these problems analytically, by running through a list of words that fit with one of the words and testing them against the others. But others got there through a flash of insight--an aha moment--in which the answer suddenly appeared to them. The researchers wanted to know exactly what was happening at those moments so they scanned people's brains as they worked to solve the puzzles. What they discovered is that a part of the brain called the anterior cingulate cortex, or ACC, lit up right before their subjects were about to have an aha moment.

One function of the ACC is to decide, when different parts of the brain are sending different signals, which of those signals to pay attention to. If a creative or odd or "long-shot" solution to a problem is bubbling up somewhere in the back of your mind, the ACC can choose to focus your attention on that solution. In other words, it can seize on your most creative ideas and bring them to the forefront of your mind.

When you need creative energy--when you're designing a new marketing campaign or trying to come up with a new product, for example--activating your ACC can really help. And you can activate your ACC by improving your mood. "When we're in a good mood, the ACC is more sensitive to odd thoughts and strange hunches," Kotler writes. "If an active ACC is the ready condition for insight, then a good mood is the ready condition for an active ACC." Or, to put it another way, if you want to be more creative, get happy.

How do you get happy, or at least temporarily happier so you can be more creative? Here are a few ideas:

1. Practice gratitude.

Paying attention to the things you have to be grateful for is one of the most effective ways there is to lift your own spirits. There are many different ways to practice gratitude, but here's the one that works best for me. Mentally list three things in your life that you're grateful for, which could be anything from the love of your spouse or partner or children, your health, the beautiful tree outside your window, or the fact that the corner deli happened to make your favorite type of soup today.

2. Open monitoring meditation.

Most of us are familiar with focused-attention meditation, in which you focus on your breathing, or on a word or phrase, or on scanning your body, or on some imagery in your mind. These are all useful techniques for decreasing your own stress and improving concentration. But if you want to activate your ACC, you need a slightly different approach, Kotler writes. "Divergent thinking requires an open monitoring style of meditation." In open monitoring meditation, you don't work to focus your attention, you simply open yourself to any thought, any emotion, or any sensation that comes to you, without judgment. Once a thought or feeling arises, name it and then let it go.

3. Exercise.

Exercise is one of the most reliable mood boosters there is. It lowers the stress hormone cortisol, and increases happy-feeling neurochemicals such as endorphins. You'll increase the benefit if your exercise takes you outside where there is nature--a walk in the park, for example--which also has proven mood-lifting benefits. "Plus, the time-out that exercise provides works as an incubation period," Kotler writes.

4. Make a connection.

Although this isn't one of Kotler's suggestions, connecting with a friend or loved one is often a great way to improve your own mood. There's even evidence that such connections can improve your longevity

There's a small but growing group of Inc.com readers who get a daily text from me with a self-care or motivational micro-challenge or idea. Often, they text me back and we wind up in an ongoing conversation. (Interested in joining? You can learn more here.) They tell me that reaching out to their friends and loved ones, even when they're struggling with work overload, is one of the best things they can do to help themselves.

So take a few moments to perhaps call one of your loved ones or engage in some chit-chat with one of your office friends. It's also a chance to talk about your project a little. That might be enough to jump-start your creativity for the task ahead.