"Plah!" A Zapotec Indian healer tilts back her head and spits a mouthful of fiery mescal on the chest of a volunteer patient, as a roomful of University of New Mexico students watch, spellbound.
"Plah! Plah! Plah!" The healer sprays more mescal on the woman's neck, hands, and thighs before passing an egg over her body to absorb the evil spirits. Then comes the culminating moment of a Mexican limpia, or ritual cleansing ceremony: The healer breaks the egg into a glass of water and inspects it for signs of impurities.
"She has very little bad energy," Doña Rosario proclaims, pointing to the perfectly formed yolk.
This is only the most bizarre moment in several days of offbeat experiences. Another is when Doña Queta, a veteran Zapotec healer, tells students that they can identify plants' medicinal uses by their resemblance to human anatomy —mirto rojo, for example, a red flower related to mint, resembles a woman's genitalia and is used to treat urinary-tract and intestinal infections.
"The plants speak to us; you just have to listen," she says during a field lecture on herbal medicine in an overgrown graveyard.
If the students are skeptical, they don't show it.
"I have no idea what I think about this, but I know there are lots of ways of the world that we don't understand," says Deborah Hall, a pediatrics professor with the University of New Mexico at Albuquerque's early-childhood-development program. "If it's about healing people, then you go where you need to go to heal."
She is one of 13 participants in a 10-day summer course on traditional medicine in the Mexican state of Oaxaca. During the program, which is part Spanish immersion, part crash course in herbal medicine, students travel from the state's colonial capital to remote, impoverished mountain villages and then down to the tropical coast. They also learn about traditional Indian methods of childbirth —from a midwife in an adobe sauna, called a temascal —and ride a boat through a lagoon to learn about the medicinal uses of aquatic plants.
The seven-year-old program is the brainchild of Terry K. Crowe, a professor of occupational therapy at the university. She fell in love with Oaxaca while studying Spanish in the city 13 years ago. At the same time, she was exposed to indigenous methods of healing, which were gaining popularity in New Mexico with the state's mushrooming Latino immigrant population.
While the course is too short to teach participants to become practitioners themselves —it takes years, or even decades to become a curandero, as the healers are known in Spanish —Ms. Crowe hopes that students will gain a basic understanding of practices that are widespread among Mexican and American indigenous communities in New Mexico.
"I particularly want health professionals to be more sensitive when they work with people of different cultures, who may be thinking about their illness differently than we do in our culture," she says.
While most of the participants are master's students in the university's occupational-therapy program, the course is open to anyone who applies, including professionals like Dr. Hall and students from other universities. Among the participants in this group is a graduate student in multicultural studies from the State University of New York at New Paltz, a New Mexico psychology professor, and an undergraduate pre-med student.
Traditional medicine —or alternative medicine, as Western medical practitioners prefer to call it —began to gain acceptance in American medical schools in the early 1990s. Of the nation's 130 accredited medical schools, more than 100 cover alternative or "complementary" medicine in at least one required course, according to the Association of American Medical Colleges, and the number continues to grow.
The University of Pennsylvania's School of Medicine, the country's oldest medical program, recently sparked a controversy by signing an agreement to collaborate on education and research with the Tai Sofia Institute, a school in Baltimore that specializes in alternative healing. Critics warned that the partnership risked legitimizing practices that lack a scientific foundation.
But to the New Mexico students, such concerns seem outdated.
The state has the nation's highest concentration of Hispanics —44 percent —including Latino immigrants and descendants of Spanish settlers. It also has the second-highest percentage of American Indians, tied with Oklahoma, after Alaska, according to the U.S. Census Bureau.
Albuquerque is home to the Ayurvedic Institute, which trains practitioners of herbal medicine, acupressure massage, yoga, and other nontraditional techniques.
The university itself also has a history of exposing students and the faculty to alternative medicine. Eliseo S. Torres, the university's vice president for student affairs, offers a summer course in traditional healing, which is taught mostly by curanderos from Mexico. In addition, university doctors offer their services at a local alternative-medicine clinic.
"Alternative medicine is pretty socially accepted in New Mexico, because there are so many cultures, and you just see it more," says Jennifer Cruz, an occupational-therapy student, who spent six years as a special-education teacher on a Navajo reservation.
Ms. Cruz was hoping that the Oaxaca trip would allow her to make sense of the practices of her Mexican grandmother. "I grew up watching her use an egg to ward off bad spirits, or she would cover you with a bedsheet to sweep off the bad juju," she says, laughing as the group's van drives past arid hillsides strewn with organ cacti and scrub brush.
The students are heading to Cuajimoloyas, a Zapotec mountain village 40 miles north of Oaxaca. Along the way, the guides stop for a survey of traditional medicinal plants used for everything from shampoo to treatments for stomach parasites and diabetes, the country's No. 1 killer.
Laurencio López Núñez, a local botanist, picks a handful of hallucinogenic "magic mushrooms," used by the Aztecs and other indigenous groups to make contact with the gods. The drug came to the notice of the counterculture movement following a 1957 Life magazine article that described a ritualistic ceremony led by a Mexican shaman in her Oaxaca village.
"It's not witchcraft," says Mr. López of the mushrooms, which contain the hallucinogens psilocybin and psilocin. "They're just powerful essences." He explains that the mushrooms also have healing properties, to cure depression and headaches.
After another half-hour drive, he and Doña Queta lead students into the pine forests above Cuajimoloyas to discover dozens more medicinal plants. The group also spends an hour chatting with another local healer, Doña Telésfora, in her wooden shack.
The poverty of the state's indigenous communities is eye-opening for many of the students.
"This is where she lives!" exclaims Steven Salcido, a senior biology major and pre-med student at New Mexico, as he ducks into the cramped room plastered with dried mud. Slabs of drying venison hang from the ceiling, alongside a primitive wood stove. Outside, squawking chickens peck in the mud.
Within minutes, however, the students are peppering the healer with questions about her healing methods and which ailments are most common in the community. "That's easy," she responds: "Mal de ojo and susto" —evil eye and fright. The treatment for both is a limpia, she explains, adding that every healing ceremony is different, "since no person's energy is the same."
She tells how her grandmother, a local curandera, began teaching her the techniques after Doña Telésfora lost a baby. "She said it was time for me to learn, so that I wouldn't lose any more children," she says.
The conversation turns to a discussion of the harmful effects of American junk food and soda on Mexican health. "Before, diabetes was a rich person's disease," says Doña Telésfora, "but now it hurts me to see what has happened to our people."
The students emerge somewhat sobered, but also inspired to learn more.
"I confess I was a little skeptical before [of traditional medicine]," says Teresa Esguerra, a 34-year-old occupational-therapy student. "I was thinking it was just a question of faith, but now that concept is more powerful to me. We need to believe in ourselves as healers, not just as Western practitioners."
For many, the trip is as much a personal journey as an academic one.
During a hot-chocolate break in the village's sole restaurant, Doña Queta performs an impromptu demonstration of her curative techniques on Daniel Rodríguez, a physical-therapy graduate student who is troubled by thoughts he does not describe. As she takes hold of his hands and begins reciting a prayer in Spanish, he breaks down sobbing. The healer is unfazed. She spits several mouthfuls of water on his chest and neck to shock him into a catharsis, and a few minutes later, he stops crying.
"How do you feel now?" she asks.
"At peace," he says quietly, turning to stare at the rain beating down on the town's mud-caked main street.
Such reactions are nothing new to Ms. Crowe. "Our first goal is to teach about traditional healing, but they also learn so much about themselves," she says. "It's a very powerful force just being with these people."
The students also learn about traditional childbirth methods from Catalina Jiménez, a 30-year-old Mixe Indian midwife. She describes how women in her village give birth inside the temascal. Many stay inside for days and even weeks, bonding with their newborn child, as a constant herb-infused steam recreates the atmosphere of the womb.
She demonstrates on Ms. Cruz, who lies down sideways on a blanket, with a mock baby stuffed inside her shirt. The midwife then massages the student's back, pretending to soothe labor pains. She also demonstrates how she helps move the baby into the head-down position, to prevent potentially dangerous breech births.
"In my village, the women have more faith in the midwives than in the doctors," says Ms. Jiménez, explaining how widespread discrimination toward Mexico's 10 million Indians deters many women from seeking the help of Western medicine.
However, when things go wrong, she says, she urges them to head to the nearest hospital —a three-hour drive along horrible roads. Once, while she was helping a woman give birth to twins, the second baby refused to come out. So Ms. Jiménez breastfed the first baby herself while helping the woman continue to push. But after 36 hours, she says, "I told her, 'if you don't go to the hospital, both you and the baby will die.'"
The woman relented, and hours later, as the doctor was preparing her for a Caesarean —the method of choice in many Mexican hospitals —the baby came flying out onto the delivery table.
She pushes down on Ms. Cruz's belly, sending the doll shooting across the floor. "That baby knew how it wanted to be born," she says, as the class erupts in laughter.