A Harvard professor and a former Harvard researcher were among three physicians who injected seven patients--including one man with a frontal lobotomy and another who was comatose--with radioactive isotopes in a 1951 experiment at Massachusetts General Hospital.

The experiment was led by Professor of Surgery Emeritus Dr. William H. Sweet, the then-research fellow Dr. Louis Bakay and the late Dr. Bertram Selverstone. The work was mentioned in a report in the Boston Globe on Sunday.

This experiment is the third that links Harvard researchers to tests on human beings involving radiation during the Cold War era. In two previously released cases, the radioactive experiments were done on retarded children.

But the Sweet experiment is the only test to come to light that involves a physician who is still a Harvard faculty member.

The published study of the experiment, which appeared in the Journal of Laboratory and Clinical Medicine and was obtained by The Crimson, says the experiments were "performed on volunteer patients, all of whom were suffering from extensive neoplasms [tumors]."

But the extent of the patients' afflictions calls into question whether they had the mental or physical capacity to volunteer for such testing. The test's subjects included:

. A 62-year-old patient with a frontal lobotomy who was described as "grossly apathetic" and lying in a "motionless torpor."

. A comatose 58-year-old patient who was said to be paralyzed on the left side of his body.

. A 65-year-old man who suffered from brain cancer and was partially paralyzed on his right side.

. Another man who was called "stuporous" and "motionless."

All but two of the seven patients used in the experiment "lay quietly or even motionless," according to the published study.

In a telephone interview from his Brookline home last night, Sweet said he vaguely recalled the experiment. He agreed that, given the test subjects' afflictions, it is unclear whether or not they could give consent.

"It doesn't seem as if all of them were able to [consent]," Sweet said. "But I'm sure that if we went ahead everything was in order."

"We didn't have all these present tactics of explaining everything in great detail, what all the risks are," Sweet said. "All this was in the last quarter of a century."

"We enjoyed a cheery relationship with the patients," the professor added. "We were both in it together trying to work for the patient's benefit."