Read the article and my point should be clear. I would have thought the sub-editors for Nature would be more careful with such stuff.
The article notes a condition I had not heard of:
“This study assures us that there were not widespread ‘acid casualties’ in the 1960s,” says Charles Grob, a paediatric psychiatrist at the University of California, Los Angeles. He has long has advocated the therapeutic use of psychedelics, such as administering psilocybin to
treat anxiety in terminal-stage cancer4.
But he has concerns about Krebs and Johansen’s overall conclusions, he says, because individual cases of adverse effects use can and do occur.
For example, people may develop hallucinogen persisting perception disorder (HPPD), a ‘trip’ that never seems to end, involving incessant distortions in the visual field, shimmering lights and coloured dots. “I’ve seen a number of people with these symptoms following a psychedelic experience, and it can be a very serious condition,” says Grob.
Krebs and Johansen, however, point to studies that have found symptoms of HPPD in people who have never used psychedelics5.