When photography was born and proclaimed the "mirror of nature," the death of portrait painting was announced.

Luckily, the prophets were way off the mark. In many ways photography liberated artists from the cozy conventions of portrait painting and set them off on a fresh discovery of the human face. The 20th-century face is explored in a new exhibition at the National Museum of Western Art, but don't expect many pretty pictures: "Visage" reflects the quest of such serious artists as Bacon, Klee and Giacometti. This is a challenging, well-presented show and includes some strong contemporary work from China and Korea.

The first gallery's theme is "creating individuality," by which the curators mean the curious way a portrait takes on a life of its own. Here is Picasso's 1937 portrait of his new mistress, Lora Maar. If any of his dislocated images of women can be called glamorous, this one can. Its vivid eroticism contrasts with a sober portrait of an old woman in intense blues.

In this room one painting shines as bright as a beacon: Modigliani's "Girl With Pigtails." Influenced at first by Cezanne and then by the study of African sculpture, Modigliani quickly developed his own insight and style. His quiet paintings of friends and neighbors go far beyond representation to evoke the inner life. This is the miracle of art: that paint can convey something as fleeting as the wariness of a child in an adult world. Although painted at a happier time in the artist's life, the child's fragility and glassy darkness of the window create a sense of vulnerability and change.

Kazuo Nakabayashi, curator of the National Museum of Modern Art, analyzes the interaction of viewer and canvas in the catalog.

Have you ever felt unsettled by the direct gaze of a painted face? Certainly the averted gaze of Matisse's "Head of a Woman" lets the viewer off the emotional hook. Without that, perhaps her strongly worked eyes would be too sad for comfort.

Self-portraits have always been revealing. Rembrandt's self-image famously changes from showy confidence with his young wife to the lonely shadows of old age. Here, Shigeru Aoki's self-portrait at the age of 21 is quite compelling. Against a decorative background, the artist stands in romantic gloom with red strokes flickering round his figure like lightning. His was a precocious talent: This was painted in 1903 while he was still a student in Tokyo. Incidentally, he was at odds with his influential teacher, Seiki Kuroda, and would promptly leave the room whenever the latter walked in. Like many of his generation, Aoki suffered from tuberculosis, and in a short life achieved fame but not fortune.

Tsuguharu Fujita was one of the happy few to enjoy a bohemian life in Paris, and his pearly skinned paintings of women are justly prized. His self-portrait of 1929 reveals a posturing youth: Like an artisan displaying his wares, Fujita sets himself in the studio, with a background of line drawings of beauties. What saves this portrait from outright vanity is the delightful tabby cat at his elbow, which clearly wants to spring at the brush in his master's hand.

Far more mysterious is a 1994 self-portrait by Kim Myung-Sook. This is a monumental image, in soft charcoal crazed with gold. Its contemplative atmosphere is something like a study by Leonardo da Vinci; it is a sea of tranquillity after Picasso's raging face.

The horrors of World War I sent many people on a search for meaning. Belgian poet Henri Michaux turned to the secret world of dreams. His sketchy, birdlike faces and manic scribbles are strangely attractive, charged with the instinctive power of cave paintings.

The next war pitched artists into a dark night of the soul, and the disintegration of humanity figures in the manic work of Jean Dubuffet. Abstract Expressionism was on the rise, but one artist who swam against the tide was Swiss sculptor Alberto Giacometti. Inspired by the archaic figures of ancient Egypt, Giacometti set himself the impossible task of creating figures that would strike the viewer with the force of living beings. Here, we can contrast a painting and sculpture of the same subject, the "Bust of Diego.' "

Two of the finest 19th-century portrait painters were American: the perceptive Thomas Eakins and dazzling John Singer Sargent. The 20th-century passion for abstraction, however, left figurative painting out in the cold. An American artist who now lives in Tokyo remembers how professors at art school in the '70s were extremely discouraging when she started painting people. Fortunately, she continued, and figurative art is now in revival.

Britain's long tradition of portrait painting survived through internationally acclaimed artists such as Francis Bacon. Recent work by China's Fang Lijun is pleasantly reminiscent of early 20th-century British artist Stanley Spencer. His tilted, blandly smiling man reveals the familiar tension between public and private faces. Finally, another Chinese artist, Yan Peiming uses the traditional power of black and white in a sweeping image of a Sudanese boy.

Strangely, portrait exhibitions attract fewer visitors than the average. If you are weary of the mass media's bland image of humanity, though, then "Visage" might be just the tonic you need.