PARIS, Dec 13 (AFP) - A strange illness has descended on Japanese living in Paris, tipping many of them in a state of profound culture shock after realising their ideals about the French capital were unrealistic, a study published in Monday's Liberation newspaper said.

More than a 100 expatriates a year are sinking into a state called "the Paris syndrome" which is characterised by feelings of persecution or suicidal tendencies, according to the mental health facilities of city hospitals.

Part of their clinical depression stems from having to reconcile their romanticism about Paris with reality, psychiatrists said.

"Magazines are fuelling fantasies with the Japanese, who think there are models everywhere and the women dress entirely in (Louis) Vuitton," Mario Renoux, the head of a French Japanese Society for Medecine was quoted as saying.

After a relatively short period of only three months or so, Japanese immigrants expecting to find a haven of civilisation and elegance instead discover a tougher existence with many problems dealing with the French.

"They make fun of my French and my expressions", "they don't like me" and "I feel ridiculous in front of them" are common refrains heard by the doctors.

The need to forcibly express one's self to be noticed - seen as vulgar in Japanese society - and exposure to a humour sometimes seen as offensive adds to the unhappiness.

"However, not wanting to give up their Paris dreams, the patients refuse to go back to Japan," the newspaper noted.

"The phenomenon manifests itself in those who are unable to adapt to France because of the shock resulting from the confrontation between the two cultures," Dr Ota, a Japanese psychologist treating some of the patients at Sainte-Anne Hospital, said.

He and other experts underlined Japan's ideal of collectivism, or putting the group first, as a barrier for some of the immigrants who suddenly find themselves in a Western society based more on individualism.

Many of those feeling victimised by the experience are Japanese women.

"They are, in general, young ladies who have been spoiled and protected. Ill-prepared for Western freedom, they often go off the rails," the head of the French association Young Japan, Bernard Delage, said.

The Japanese consulate in Paris said there were 14,000 Japanese registered as living in Paris, and thousands more unregistered. Most are students, artists, businessman and employees of international companies.