What exactly is it that makes us happy? Scientists at Kyoto University might have found an answer, using imaging technology to scan the brains of participants and understand how different people experience happiness. Oliver Hotham speaks to programme-specific associate professor Dr Wataru Sato about the groundbreaking research, his influences, and its implications for the treatment of neurological and mental health problems.

Go to your happy place – treatment of neurological and mental health problems

Psychiatrist and philosopher Victor Frankl spent a lot of time thinking about human happiness. A Holocaust survivor, almost his entire family perished in the concentration camps, and the pain and suffering that dominated his early life left him fascinated with our species’ desire to lead happy lives, and why satisfaction can be so elusive.

"If there is a meaning in life at all, then there must be a meaning in suffering", he wrote in his seminal book Man’s Search for Meaning, an account of his experiences, published just a year after the liberation of Auschwitz. "Suffering is an ineradicable part of life, even as fate and death."

Frankl would go on to have an extraordinary impact on psychologyand how we think about the search for happiness in day-to-day life. He coined the phrase ‘Sunday neurosis’, for example, which describes the emptiness many feel when the hustle and bustle of the working week is over and "the void within [our]selves becomes manifest". His lectures all over the world were legendary, and he lay much of the groundwork, along with philosophers Friedrich Nietzsche and Soren Kierkegaard, for the existentialist movement in psychology.

Decades on, Frankl would make perhaps one of his greatest contributions to the study of happiness, inspiring Dr Wataru Sato, with a team of researchers at Kyoto University, to set out with the complex objective of unravelling the neurological behaviour that guides it.

We found a positive relationship between the subjective happiness score and grey matter volume in the right precuneus.

"Frankl proposed that humans search for meaning and purpose in life," says Sato. "I liked this philosophical attitude that subjective happiness is more than just pleasure and displeasure."

Also influential were Jeremy Bentham and Aristotle, both of whom saw the search for joy as central to the human experience. Bentham, for example, posited that the essential purpose of civilisation should be to maximise happiness – in a general, public sense, and in an individual, spiritual and material sense.

The best-kept secret

The report set out to do two things: to find a way to measure subjective feelings of happiness, and to identify the ‘neural mechanism’ of this kind of happiness. 51 patients were brought in and underwent MRI brain scans, before answering a series of questions about their general happiness and satisfaction with life.

"The neural substrate of subjective happiness remains unclear," explains Sato. "To investigate this issue, we acquired structural MRI, and assessed subjective happiness and some related constructs (positive and negative emotional intensity, and purpose in life) using questionnaires."

The team conducted a statistical parametric mapping analysis, investigating the association between grey matter volume and the measured subjective happiness, combining the scores of negative and positive emotions.

Many of the answers lie in a part of our brains called the precuneus, a less-understood region of the brain, which, due to its location far away from potential operating scalpels, has been described as ‘one of the less accurately mapped areas of the whole cortical surface’. What we do know, however, is that it plays an important role in consciousness, our sense of self and, as a consequence, happiness.

The researchers found that those who scored highly on the happiness survey – feeling joy more intensely and sadness mildly – exhibited significantly higher levels of grey matter on this part of their brain than those who scored lower. Psychologists have known for years that it’s this combination of satisfaction with life, a sense that our emotional needs are being met and physiological factors that determine our predisposition towards happiness, but what’s fascinating about this research is that the theory can be reflected in our physicality.

"We found a positive relationship between the subjective happiness score and grey matter volume in the right precuneus," summarises Sato. "Moreover, the same region showed an association with the combined positive and negative emotional intensity, and life-meaning scores."

But those with lower levels of grey matter on the precuneus are not stuck in this state forever, and a key motivator of Sato’s research was to develop ways in which patients could be ‘trained’ to feel happier. Previous structural MRI studies have revealed, he points out, that activities like meditation and mindfulness can increase the grey matter in the precuneus.

"Psychological studies also reported that meditation had an effect on depression," he says. "With this data, we speculate that it may be possible to develop evidence-based training programmes, practicing meditation and checking the precuneus structure, to improve happiness.

"Furthermore, it may be possible to use electrical or chemical stimulation on the precuneus to boost subjective happiness. The new insight on where happiness happens in the brain will be useful for developing programmes based on this kind of scientific research."

A growing interest

Sato’s report ‘The structural neural substrate of subjective happiness’ states, "To date, no structural [MRI] investigation of the construct has been conducted." It continues, "Identification of the neural substrates underlying subjective happiness may provide a complementary objective measure for this subjective construct and insight into its information-processing mechanism.

"These results indicate that the widely accepted psychological model postulating emotional and cognitive components of subjective happiness may be applicable at the level of neural structure."

Sato has a background studying the esoteric end of the neurological spectrum. He has spent the last fifteen years, along with his team, studying the science of emotions and consciousness.

"Usually we study emotional experience in response to short-term stimuli," he says. "Like films or photos of facial expressions."

His work on emotions led him into the world of the philosophy of consciousness and happiness, which is how he discovered Frankl and decided to extend his research. It was a good move: once completed and the findings released, the results sparked international interest and press coverage from the science and trade presses alike, as well as wider mainstream media. Headlines declared ‘Scientists locate the brain’s happiness centre’ and ‘Happiness arises from the seat of consciousness in the brain’: a slight simplification of the findings, but pleasant attention nonetheless for Sato, a mild-mannered and thoughtful scientist who had spent much of his career toiling in relative obscurity. For him, it was vindication that years of work into the neurological roots of subjective happiness have been worthwhile.

"I got surprised!" he admits, when asked how he finds the media attention. "Usually many people don’t pay attention to my research, so actually, I got surprised. After that, I received several emails from researchers I was unfamiliar with, and it was quite interesting to exchange information with them.

"I knew that happiness is quite important, especially for humans, but now I know that many people have a strong interest in subjective happiness."

The definition of success

There are other implications of Sato’s findings, too; particularly about the role that the precuneus might play in human evolution. Recent comparative MRI studies, for example, have shown that the chimpanzees have a smaller precuneus than humans – suggesting that happiness, and our ability to experience it, could be a sign of a more evolved species and a more advanced consciousness.

The search for the meaning of life and the path to happiness has always been seen as the ultimate intellectual and philosophical pursuit. Governments and social scientists have always wanted to unravel it, of course, and the existence of ‘unhappy people’ have a range of knock-on effects on society: from lower productivity to social revolution – it was, after all, the suicide of a depressed 26-year old in Tunisia by self-immolation that sparked the Arab Spring in 2011. Some, like the mountain kingdom of Bhutan, measure Gross National Happiness (GNP), and some, like the government of the United Arab Emirates, operate Ministries of Happiness "to create social good and satisfaction".

Many would argue happiness is impossible to measure: there are so many social, psychological, and philosophical factors to take into account when trying to understand why some feel joy so vividly and others do not. For most of history, these questions have remained the preserve of philosophers, but now we see that imaging may be able to step in to help.

Next, we would like to understand the functional neural mechanism of subjective happiness.

Not everyone is entirely convinced, of course. An article in Psychology Today argued that the study’s definition of happiness as "a combination of happy emotions and satisfaction of life coming together in the precuneus" is not a universally accepted definition of the phrase, comparing it instead to the Greek phrase eudaimonia, which roughly translates to ‘human flourishing’. It makes sense that a study with such grand objectives would attract some scepticism, but even those not completely sold by Sato’s findings accept that all signs point to the precuneus as the root of feelings of happiness.

Defining happiness is obviously a major intellectual challenge. The concept differs from culture to culture, let alone from person to person: for some, happiness is material success, for some it’s family, and for others it’s freedom and creativity. This is why Sato and his colleagues were forced to compartmentalise a little: there’s no concrete way of measuring precisely how happy someone is by scanning their brain – unless they’re seriously ill.

"It’s quite difficult to define subjective happiness," he admits. "But operationally, we can define it as the score of our subjective happiness questionnaire – we didn’t want it to be too philosophical – so we took this operational definition in the study."

Buoyed by the interest and determined to expand on these findings, Sato and his team now have much more in mind, and the next step is trying to understand the actual physicality of positive emotions – and after that, consciousness itself.

"Next, we would like to understand the functional neural mechanism of subjective happiness," he says. "Specifically, we will investigate its haemodynamic neural network dynamics (interactions between brain regions) and electric neural correlation. I want to understand how neurons produce subjective consciousness."