Depression was not widely recognised in Japan until the late 1990s

When an advertising campaign called it a "cold of the soul" sales of anti-depressants boomed

Now some have been accused of faking depression to get time off work

Image copyright Torisugari

I'm sitting on a psychiatrist's couch in southern Japan, turning the pages of a manga by the artist Torisugari.

The artist himself sits beside me, talking me through it in hushed tones. We pause over an image of the manga's main character starting to plummet downwards as the Earth fragments and gives way beneath his feet

Image copyright Torisugari

"The world that had supported me up until now is breaking up and falling away! I can't even stand up any more!" says the character, Watashi (whose name means "I" in Japanese).

The image represents the artist himself more than a decade ago. Working impossible hours at his job as a civil servant, often going without sleep, one day he found a single thought circling round and round in his head: "I have to die."

Torisugari had no idea what was happening, and his fear was deepened by the incomprehension of those around him. He kept a suicide attempt secret from his parents, instead going to a doctor to have his heart checked out - there was nothing wrong with it.

At the age of 29, Torisugari was embarrassed to find himself begging his mother not to leave the house without him.

Image copyright Torisugari Image caption Watashi says: "Don't go! Don't abandon me!" The response: "That's enough of that!"

Image copyright Torisugari

His father insisted this was all just attention-seeking. His best friend said the same and told him to get some exercise

Everything in his life seemed to be disintegrating - the world was becoming a strange place, and his relationships were failing him.

Finally, another doctor gave Torisugari a diagnosis: depression. He had never heard of it.

There was nothing unusual about this. Up until the late 1990s in Japan, "depression" was a word rarely heard outside psychiatric circles. Some claimed this was because people in Japan simply did not suffer depression. They found ways to accommodate these feelings while somehow carrying on with life. And they gave low moods aesthetic expression - in art, in film, in the enjoyment of cherry blossom and their fleeting beauty.

Image copyright Torisugari Image caption Watashi receives the diagnosis: "Mr K this is 'depression'. I'm going to give you some medicine - please come back with your boss."

Christopher Harding's The Borders of Sanity was first broadcast on BBC Radio 4. Listen online here.

A more likely reason is Japan's medical tradition, in which depression has been regarded as primarily physical rather than a combination of physical and psychological, which would be more common in the West. While the diagnosis itself was rarely used, people suffering classic symptoms were likely to be told by their doctors that they simply needed to rest.

All this made Japan such a poor prospect as a market for anti-depressants that the makers of Prozac all but gave up on the country. But then at the end of the 20th Century a remarkable marketing campaign commissioned by a Japanese drugs firm helped turn things around.

Word was spread about depression as kokoro no kaze - a cold of the soul. It could happen to anyone, and medication could treat it.

The number of people diagnosed with a mood disorder in Japan duly doubled in just four years, as the market for anti-depressants boomed - in 2006 it was worth six times what it had been just eight years before.

In a country as open as any other to the celebrity confession, everyone from actors to newsreaders now seemed willing to come out and say they had had an experience of depression. This new illness was not just acceptable - it was even slightly fashionable.

Image copyright Torisugari

Depression also entered the courtroom. The family of Ichiro Oshima took his employer - Dentsu, Japan's largest advertising agency - to court, after Oshima killed himself following months of heavy overtime.

The legal battles that followed garnered huge public attention, as the family's lawyers successfully showed two things: depression could be caused by a person's circumstances, including overwork - it was not purely about genetic inheritance, as Dentsu tried to argue - and Japan's still-prevalent ideas about suicide as straightforwardly intentional, even noble, were inadequate.

Japan's leaders were rattled. Mental illness had gone from a hush-hush family matter to the focus of a workers' movement. And what had once been a natural expectation that working women especially would "sell their smiles for free" - helping create the eager willingness and inexhaustible good cheer that Japanese customers have come to expect - was now being talked about as "affective labour": emotional or psychological graft.

A suicide prevention law was passed in 2006, pledging to reduce suicide rates and declaring suicide a social rather than just a private problem.

Image copyright Torisugari

And since 2015 Japan has brought in workplace stress checks. A completed questionnaire covering causes and symptoms of stress is assessed by doctors and nurses, leading to medical care for those who need it - with results kept confidential from employers. This is mandatory for companies with more than 50 staff, and smaller businesses are also encouraged to do the same.

With plenty of public debate, lots of medical and celebrity support, and progressive employment measures, does Japan now firmly "believe" in depression?

Well, maybe - and maybe not. There's evidence of a pendulum swing in the opposite direction, as a rapid rise in work absences and sick leave due to depression seems to be generating a climate of frustration at the impact on colleagues and now even suspicion about the way some people obtain and use a diagnosis.

Some Japanese suffering with depression find that while the rise in public awareness about the condition has been a comfort to them, allowing them to talk openly, their recovery and return to work is hampered by cynical talk around them about "fake" or "bogus" depression - a sign of self-indulgent times.

Image copyright Torisugari

The limitations of that "cold of the soul" campaign are becoming clear. It was criticised at the time for making misleading links between the common cold and depression. But beyond that, Japan's experience with depression shows how closely tied some forms of physical and mental illness are to broader cultural attitudes - about work, for example, and levels of responsibility towards others. Raising public awareness ends up being a complicated, delicate task.

No-one knows this better than Torisugari, who still has to contend now with both his illness and with some of the same misunderstandings he faced in those early, surreal weeks. Which is why he's decided to produce the drawings we're looking at here, and why his manga are garnering an ever-larger and more appreciative audience in print and online. For him it's a kind of "manga therapy", as his psychiatrist calls it. For others - whether suffering with depression or not - it offers help in understanding the condition.

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