"Quand ils évoquent leurs hallucinations, les marins rapportent tous des conversations qu’ils ont eues, raconte-t-il. Des choses qu’on retrouve dans les descriptions que font les gens qui ont pris de la drogue, notamment du LSD. Des dissociations, des perceptions tronquées, l’impression de vivre ailleurs des moments très particuliers. Par exemple, le fait d’avoir la sensation de recevoir des copains et de servir l’apéro comme s’ils étaient chez eux."
I’m aware that it’s in my head rather than a real sound occurring in the room. The timbre is usually somewhere between humming and breathing mixed with an orchestra. It gets extremely vivid when I’m tired or stressed, to the point where it can keep me awake. Sometimes at moments of extreme emotions (positive or negative ones) I start to perceive colours too, in the same way that anyone can see anything in their mind, but it’s always the same colour (a neon green on a background of very pure white and black).
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.
Consultants from the addiction centre at St George’s Medical School, London, have published a case report of a British man estimated to have taken around 40,000 pills of MDMA, the active ingredient in ecstasy, over nine years. The heaviest previous lifetime intake on record is 2,000 pills.
(…) he still suffers from severe physical and mental health side-effects, including extreme memory problems, paranoia, hallucinations and depression. He also suffers from painful muscle rigidity around his neck and jaw which often prevents him from opening his mouth.
His condition deteriorated and he began to experience recurrent tunnel vision and other problems including hallucinations, paranoia and muscle rigidity.
For 10 years, MDMA has been suspected of causing these kinds of effects in heavy users. It is thought to be due to its disruption of the regulation of serotonin, a brain chemical believed to play a role in mood and memory.