The idea of biophilia — that humans innately love spending time in nature — has been around for generations. It was elevated to a scientific concept during the 20th century's ecological awakening, first by psychologist Erich Fromm and later by ecologist E.O. Wilson. And earlier this year, the musician Björk gave it pop-culture currency by naming her new album "Biophilia."

 

But while it's well-known that we get psychological benefits from nature in general, it's not always clear which parts of nature provide those perks. Is a city park as good as an old-growth forest? What about less verdant natural settings, like deserts or tundras? Can those offer biophilic benefits, too?

 

Scientists have been unraveling more and more of this mystery in recent years, shedding new light on the human brain in an ecological context. Much of the focus has been on visual hallmarks of nature (like trees, flowers, mountains or beaches), but a potentially groundbreaking new study takes a slightly different approach. Set to unfold over the next three years, it aims to reveal how bird songs affect human brains.

 

Lead researcher Eleanor Ratcliffe, a Ph.D. candidate in environmental psychology at the University of Surrey, says the study can fill a scientific void. "A great deal of anecdotal evidence suggests that we respond positively to birdsong," she tells the Guardian. "However, currently there is a lack of scientific research on the psychological effects of listening to birds." Past studies, for example, found that bird songs make traffic noise more tolerable, make people feel less crowded and can even mediate circadian rhythm, but few have looked at their broader impact on mental health.

 

With funding from the U.K. National Trust and the Surrey Wildlife Trust, Ratcliffe will begin by interviewing a representative sample of the public to gauge their perception of natural sounds, including bird calls. She'll try to find out if avian arias "can improve mood and attention after stress or fatigue," she explains on her website. Later in the study, she'll seek test subjects via social media — including tweets, of course — to assess the effects of bird songs on their brains and behavior.

 

Beyond that, Ratcliffe hopes to learn more about which kinds of bird songs boost mental health, and in what ways. Not all birds sing the same tune, so she'll suss out whether the soothing sounds of a thrush or warbler affect people differently than the harsher calls of crows or magpies. She'll also test reactions to recorded bird songs, an effort to see how the study might apply to daily life. If a city dweller listens to birds on an iPod, for instance, could it mimic hearing them sing in person?

 

We'll have to wait for definitive answers, since the study is scheduled to take three years. But as National Trust ecologist Peter Brash argues, dedicated birders already know the benefits of a chorus from the canopy. "Birdsong is one of the most distinctive sounds from the natural world, and gives us a warm glow inside when we hear it," he suggests on the National Trust's website. "We're all attuned to the need to eat five fruits and vegetables a day or take a 30-minute walk. Taking the time out to listen to five minutes of birdsong every day could be as beneficial to our well being."

 

So while the partridge in a pear tree may not reveal its secrets this Christmas, maybe by 2015 we'll finally know how joyous the world really is when heaven and nature sing.

 

To test the effect on yourself in the meantime, check out this compilation of bird calls:

 

 

Also on MNN:

• Ravens use beaks and wings to communicate
• Twitter reveals what time we're happiest
• Spending time in nature: The secret to good health?