Everyone wants to be happy. Yet despite all our efforts in pursuit of this prized emotion, it can be a surprisingly nebulous goal. What is "happiness," exactly?

That question has puzzled philosophers for thousands of years, and it's still tricky for anyone to tackle. But recent advances in neuroscience have finally begun to shed light on it, and now a new study claims to have found an answer. Being told happiness is "all in your head" may seem both obvious and dismissive, but in this case the specifics are also empowering. The more we know about how (and where) happiness happens, the less helpless we'll be to summon it when we need it.

By comparing magnetic resonance imaging (MRI) with questionnaires about emotional states, researchers from Kyoto University in Japan say they've traced the experience of happiness to a specific part of the human brain. Overall happiness, they conclude, occurs when positive emotions combine with a sense of life satisfaction in the precuneus, a region of the medial parietal lobe that's linked to important brain tasks like episodic memory, self-reflection and consciousness.

Psychologists already distinguish between broad life satisfaction and "subjective well-being," since happiness often seems to fade during bad moods without necessarily plunging us into deeper existential despair. But by revealing the neural mechanics of how these feelings combine to create overall happiness, the authors of the new study hope to make it easier to objectively quantify this mysterious and elusive emotion.

"Over history, many eminent scholars like Aristotle have contemplated what happiness is," lead author Wataru Sato says in a press release. "I'm very happy that we now know more about what it means to be happy."

MRI brain scansScientists used MRI brain scans to identify happiness in a brain region known as the precuneus. (Photo: Kyoto University)

To pinpoint the location of happiness, Sato and his colleagues first used MRI to scan the brains of their study subjects. Those participants then took a survey, which asked about their general sense of happiness, the intensity of their emotions and the degree of their overall life satisfaction.

After analyzing the data, the researchers discovered that those who scored higher on the happiness survey also had more gray matter mass in the precuneus. That means this brain region is larger in people who feel happiness more intensely, feel sadness less intensely and who are better able to find meaning in life.

"To our knowledge, our study is the first to show that the precuneus is associated with subjective happiness," the researchers write in the journal Scientific Reports.

Complex phenomena like happiness rarely boil down to a single brain region, but other recent research also points to an outsized role for the precuneus. A study published this month links impaired connectivity in the precuneus to depression, for example, and a 2014 study suggests the region is a "distinct hub" in the brain's default-mode network, which is active during self-reflection and daydreaming.

All this may seem like an esoteric quest for neuroscientists, but it's about more than just academic curiosity. By knowing which parts of the human brain generate our sensation of happiness, we might develop more accurate ways to test methods of becoming happier, like travel, exercise or meditation.

"Several studies have shown that meditation increases grey matter mass in the precuneus," Sato says. "This new insight on where happiness happens in the brain will be useful for developing happiness programs based on scientific research."

Russell McLendon ( @russmclendon ) writes about humans and other wildlife.