CATHERINE LOERKE, a first-year Yale medical student, peered at a slender young man whose upper torso was hanging limply over the side of a bed, his right hand touching the floor. His eyes were closed, but she could not tell whether he was breathing. Was he dead, or alive?
''This man is not sleeping,'' she announced to her fellow medical students gathered around the scene. ''How do you know that?'' asked Dr. Irwin M. Braverman, the Yale professor leading the diagnosis. ''He's green!'' she said.
While it appeared that Miss Loerke's bedside manner might need a little polish, as far as Dr. Braverman was concerned, her observational skills were sharp.
The young man was slightly green, but it was oil paint, not cyanosis, that was the cause. The body being diagnosed by the students was actually a painting in the Yale Center for British Art depicting the suicide at age 17 of the 18th-century poet Thomas Chatterton. Ms. Loerke was one of about 20 first-year medical students participating in Dr. Braverman's three-hour clinic, ''the patient-doctor relationship,'' at the Yale University School of Medicine. It's a mandatory course in which the Yale Center for British Art in New Haven serves as hospital room, paintings as patients and students as sleuths. In this class, art often imitates death.
This is the second year that Yale medical students have been required to take the course, which Dr. Braverman and Linda Friedlaender, curator of education at the Yale Center for British Art, developed four years ago to improve students' diagnostic and observational skills at an early stage in their medical training.
Students are asked to observe four paintings for about 15 minutes at a time and then, one by one, describe what they see in great detail. Dr. Braverman said the course grew out of his own observations over his 50-year career as a dermatologist that many doctors depend too much on the latest technological advances, like magnetic resonance imaging and CT scans, forgoing the old-fashioned skill of simply looking at a patient.
''Astute observational skills are usually acquired only after about five years of being in medical practice,'' Dr. Braverman said. ''Suddenly, all of the accumulated experience leads doctors to see things they have not been taught before. They become terrific observers.'' Acquiring this skill takes so long because, Dr. Braverman said, medical students in the United States have always been taught by rote.
''You teach students to memorize lots of facts,'' he said. ''You say: 'Look at this patient. Look at how he's standing. Look at his facial features. That particular pattern represents Disease A, and this pattern represents Disease B.' We teach those patterns so that the next time the doctor comes across it, he or she comes up with a diagnosis.''
But what's sorely missing in today's medical education, Dr. Braverman said, is how to think when an oddity appears.
''With this course, I wanted to jump-start these special diagnostics skills with first-year students so they can experience it from Day 1,'' he said. Brad Raphael, a 24-year-old medical student from Syracuse, said he did not know what to expect from the three-hour clinic at the museum. ''I had taken some classes in art history as an undergraduate, but nothing along the lines of having to describe a painting in great detail,'' he said. ''It definitely taught me to be more observant, which is good because sometimes you can overlook the obvious in medicine.''
Mr. Raphael said that in his two visits to hospital patients since the clinic last month, he had noticed that he was making more observations. ''It's all in the details,'' he said.
Students are not only required to describe what they see in the paintings. Dr. Braverman and Ms. Friedlaender, who participates in the museum visits, also ask them to paint a picture of what they think is going on without sneaking a peek at the descriptive plaque next to each work of art. Mr. Raphael was chosen by Ms. Friedlaender to describe ''Mrs. James Guthrie,'' an 1864-65 painting by a Victorian artist, Lord Frederic Leighton. The painting portrays Ellinor Guthrie in a black taffeta gown holding a flower from a bouquet in a vase. She and her husband lived in a fashionable and affluent house in London, and between 1857 and 1868 had nine children. The painting's flowers, vases, embroidered tablecloth, ornate chair and large tapestry in the background suggest a world of beauty and culture.
But all was not as it seemed as Mr. Raphael began making his observations. ''I see a Caucasian female in her late 20's, early 30's,'' he said. ''That's a judgment. Use other words,'' Ms. Friedlaender said.
''I see a woman with a very soft complexion, a round face that's smooth, with no wrinkles,'' he said. ''The room is decorated in solid colors. The chair is carved wood. I see two bouquets. The flowers look like they're dying.''
''That's a value judgment,'' she said. ''You've got to back that up visually.''
''She doesn't look happy,'' he said.
''Again,'' Ms. Friedlaender said.
''Her facial expression is not a smile,'' he said. ''It's more melancholy.''
''I want more visual information,'' Ms. Friedlaender interrupted.
''Her mouth doesn't show much emotion. Her eyes look tired,'' he said.
''Because?'' she asked.
''They're closing?'' Mr. Raphael said. It was more of a question than an answer.
Later Dr. Braverman asked another group of students to analyze their observations of ''Mrs. James Guthrie.'' He called it ''differential diagnosis'' -- putting the details together to find out what the story was behind it. He asked, ''What doesn't make sense here?''
One student said, ''The flowers are dead.''
''Yes, good,'' Dr. Braverman said. ''But what about the spatial characteristics? Look at where the chair is in relation to the table. And look how close Mrs. Guthrie is standing near the wall. Take in the whole scene from front to back and side to side. Make believe you're a doctor who just walked into the room. She's hemmed in. What does that mean?''
No one answers.
''By 26, Mrs. Guthrie has had five children. By 35, she's had four more children,'' Dr. Braverman said. ''Her husband died at 35. Think about having five children by age 26.''
Nothing from the students.
''Doesn't this painting reflect her life as a Victorian lady?'' Dr. Braverman asked. ''You come away with the feeling that she's had an unhappy life.''
The students nodded in agreement.
So far the team has watched as about 350 students have described the paintings. ''No, we haven't heard it all,'' Ms. Friedlaender said. ''We try to use the same pictures for control's sake, but I've never had a student approach a painting the same way. One student gave dimensions. In two years no one ever did that. Another mentioned the frame. Some work from top to bottom, some from outside in. Some are meticulous. They are all just really good.''
A clinical study developed by Dr. Braverman and Ms. Friedlaender has shown that students' diagnostic skills were 56 percent better than those of students who did not take the class.
Other medical schools have taken notice of those findings: Cornell University is conducting similar clinics at the Frick Museum in New York City and Brown University and Tulane Medical School have expressed an interest, Ms. Friedlaender said.
Tammy Vanderwal, 26, of British Columbia, took part in an exchange with Dr. Braverman over the 1833 painting ''Madras, or Fort St. George, in the Bay of Bengal -- A Squall Passing Off,'' which depicted a raging storm on a beach on the Bay of Bengal in India. In it, a few boats are heading toward the shore, but one small wooden boat with some men in it appeared to be heading out to sea on the crest of a huge wave. Dr. Braverman explained that the boat was attempting to rescue some people in the water.
Miss Vanderwal said she felt they instead were trying to avoid being dashed against some rocks. She said the conversation was ''quite telling. The aim was to look at this painting and say what you see. To do that with someone who had seen this painting so many times, it was great, but frustrating. You can have two people looking at the same situation -- or patient -- and you're both looking at the same symptoms, or signs. Someone comes in who's seen it thousands of times and the other hasn't, so you're having totally different experiences.''
Photos: Above, Brad Raphael of Syracuse, left, and Chris Kwong of San Francisco examine Thomas Chatterton in their course to hone observation skills. Left, Linda Friedlaender reviews Mr. Raphael's comments on ''Mrs. James Guthrie.''; Catherine Loerke, Dr. Irwin Braverman, a professor, and other Yale medical students discussing ''The Death of Chatterton'' by Henry Wallis.; Tammy Vanderwal of British Columbia studies ''Madras, or Fort St. George, in the Bay of Bengal -- A Squall Passing Off,'' an 1833 painting. (Photographs by C. M. Glover for The New York Times)