The work is the stuff of science fiction—transplanting the head of one animal to the body of another—but the moral questions it raises are as ancient as the Bible. Since 1970 Dr. Robert White, a renowned Cleveland neurosurgeon and authority on diseases of the brain, has performed the operation in his laboratory 35 times. The hope is that someday such delicate surgery might be possible for human beings. With that in mind, as a scientist and devout Catholic, Dr. White asks: "If the human brain is transplanted, what are the philosophical and ethical considerations? Is the brain the same? Where is the soul? Where's this mind we all talk about?" The questions are not simply rhetorical.

White's experiments with animals (mostly monkeys and rats) are not intended to mirror Dr. Frankenstein and create a new life, but to study the brain in isolation from the body. "I can alter the environment, produce abnormal states like injury, cancer or stroke," he says. "I can manipulate conditions with extremely high drug dosages or with extremely low temperatures. The brain in isolation becomes a little laboratory all its own."

The resulting studies on how the brain functions—its oxygen and glucose demands, its hormonal secretions—are conducted with a precision impossible if the monkey's head were connected to its own body.

It took years of preparation before White successfully removed the brain of a rhesus monkey in 1963, stopped its deterioration in the first few crucial minutes with a special cooling technique and kept it alive for five hours. He did his first head-to-body transplant in 1970; two monkeys since have lived a week with new bodies. (Transplanted heads cannot control their bodies, however. "No one," says White, "has any notion how to connect 100 to 200 million severed nerve ends.")

His experiments with cold (41 to 46 degrees Fahrenheit) have proven useful in human brain surgery and—surprisingly—in repairing spinal cord damage. For reasons not entirely understood, chilled saline solution circulated around the injury can sometimes arrest and even reverse paralysis. White's discoveries, says Dr. Paul Bucy, editor of the journal Surgical Neurology, are "among the most outstanding contributions in the last quarter century. His work was revolutionary in the broadest sense."

White, 53, began his surgical research at Peter Bent Brigham Hospital in Boston and the Mayo Clinic while treating children immobilized by spinal cord injuries. A graduate of Harvard Medical School, the surgeon was raised, along with a brother and two cousins, by his mother and aunt after his father was killed in World War II. He worked in construction while in high school and the College of St. Thomas in St. Paul, Minn. (The high school biology teacher told young Robert that his dissection of a frog was the most skillful he'd ever seen.)

Dr. White has become a sought-after lecturer in Russia and China as a result of his experiments. He was also invited to Rome five times by Pope Paul VI to discuss the medical and moral definitions of death. ("I don't have any problem with that," he says. "When the brain is dead, the person is dead, even though the heart may be beating and the lungs breathing.") White's travels and his long hours in the operating room and lab leave him less time than he would like for wife Patricia and their six boys and four girls, aged 8 to 23. Every day he is in town, however, White and his wife meet "as many of the kids as happen to be around" for sundaes at an ice cream parlor near their Shaker Heights home.

The doctor has a sometimes whimsical sense of humor. He admits to having passed himself off as a mind reader, an airline executive and a professor of Jewish history. "It's a way of shielding myself from having to talk with strangers about what I do," he says.

White has no such reticence in discussing prognosis and treatment with his neurosurgical patients—using such down-to-earth terms as "plumbing," "wiring" and "shunting." "The patient-doctor bond doesn't end after surgery," he adds. "I tell patients and families, 'We're in this together and for a long time.' " Perhaps because of such an attitude, he has never been sued for malpractice.

White attends Mass daily, prays before and after every operation and finds no contradiction between his profession and his religion. "I feel," he says, "there are immense resources behind me, resources I need and want."

The transplantation of a human head, he says, is technically feasible. A colleague points out that it would be easier than with monkeys because the veins, arteries and muscles are much larger. The result, in White's phrase, would be "a head-on-a-pillow," a head that could neither speak nor move but would retain intelligence, memory and personality. It is even possible that vocal cords could also be transplanted. Thus, the head of a genius could theoretically be attached to a healthy body in order to benefit from his or her wisdom longer. "The techniques are there," White acknowledges, "but then we must argue the rights and wrongs of fabricated man."

White insists a more immediate challenge "is to explore the questions, What is the brain? How does it do what it does? It's just a sac of tissue, weighing 1,400 grams. Why does it think?

"I feel we're on the edge, pretty much as we were before Einstein came along and made that quantum jump from Newtonian physics. But there's got to be a reexplanation of the brain-mind function. We need a new dimension that will have to combine neuroscience with higher mathematics and philosophy."

In spite of his scientific detachment, White acknowledges an immense respect for the organ he has analyzed in such detail. "I am more than ever in awe of the brain," he says. "It is where the human spirit and soul reside. It contains the essence of us."