Dr. Nora Volkow, director of the National Institute on Drug Abuse, said observational studies of people like the Duke work can’t definitively demonstrate that marijuana causes irreversible effects on the brain. In an email, she said Rogeberg’s paper “looks sound” but doesn’t prove that his alternative explanation is correct either.
American scientists deliberately infected prisoners and patients in a mental hospital in Guatemala with syphilis 60 years ago, a recently unearthed experiment that prompted U.S. officials to apologize Friday and declare outrage over “such reprehensible research.”
The U.S. government-funded experiment, which ran from 1946 to 1948, was discovered by a Wellesley College medical historian. It apparently was conducted to test if penicillin, then relatively new, could prevent infection with sexually transmitted diseases. The study came up with no useful information and was hidden for decades."
The paper details three different experiments in which participants read about or actually performed a series of simple actions, such as shaking a bottle or shuffling a deck of cards. Then they watched videos of someone else doing simple actions - some of which they had done and some they had only seen being done.
Two weeks later, they were asked which of as many as 30 actions they had done themselves. Researchers found the subjects were much more likely to falsely remember doing an action if they had watched someone else do it.
Echterhoff says the research controlled for the common situation of thinking you had done something because you do it yourself every day. And, he says, participants had false memories even when cautioned about the possibility."
The team studied 52 heart attack patients who had been admitted to three major hospitals and were eventually resuscitated. Eleven of the patients reported near-death experiences.
“We found that in those patients who experienced the phenomenon, blood carbon-dioxide levels were significantly higher than in those who did not,” said team member Zalika Klemenc-Ketis, of the University of Maribor in Slovenia.
How carbon dioxide might actually interact with the brain to produce near-death sensations was beyond the scope of the study, so for now “the exact pathophysiological mechanism for this is not known,” Klemenc-Ketis said.
However, people who have inhaled excess carbon dioxide or have been at high altitudes, which can raise the blood’s CO2 concentrations, have been known to have sensations similar to near-death experiences, she said."