Slashdot reader and Motherboard writer dmoberhaus was the final participant in the world's first brain imaging study on salvinorin A, the psychoactive chemical in salvia divinorum. He wrote about what it's like to participate in a psychedelic drug trial, and why he volunteered to smoke the world's least favorite hallucinogen for science. Here's an excerpt from his report: I was first introduced to salvia when I was a freshman in high school, and by the time I graduated I had smoked it about a dozen times. In retrospect, I would not describe a single one of those experiences as "pleasant," "enjoyable," or "fun." The last time I used salvia was almost a decade ago, and during that trip I became convinced that I had been irreversibly transformed into a suspension bridge. Good times. Despite a history of bad experiences with the substance, I volunteered for the Johns Hopkins salvinorin A study out of a suspicion that salvia probably had more to offer than what I experienced in high school. As a teen, each of my salvia experiences was under less than ideal conditions -- usually at a party or in a park after curfew. These sorts of situations lend themselves to paranoia and anxiety, which don't mix well with a strong dissociative hallucinogen. I figured if the settings were changed to a relaxed environment where I was surrounded by medical professionals, perhaps the nature of the trip would as well.
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For the first salvia session I laid on the couch and donned an eye mask while [Manoj Doss, a postdoctoral researcher who specializes in memory] sat at the far end of the room with the smoking apparatus. The simple device consisted of a small glass bulb with a plastic hose connected to the top and was described to me as an "FDA-approved crack pipe." Along the bottom of the bulb was a barely noticeable residue of a white crystalline substance, which I was informed was one dose of 99.9% pure salvinorin A. I was given one end of the hose and instructed to begin a 45-second long inhale as Doss vaporized the salvinorin A with a butane torch. At the same time, Clifton began to play a new age soundtrack through speakers and came to put his hand on my leg to ground me during the trip. When the 45 seconds were up, I exhaled and felt the effects of the salvia almost immediately.

The first thing I noticed was the feeling of my body dissolving. Shortly after I began feeling the physical effects, the hallucinations began. I felt as though my head had split in two and a patterned stream began flowing from both sides of my face. This stream was a "harlequin pattern" of large brown and white diamonds that flowed away from me and began to form the "boundary" of an infinite three-dimensional space. These diamonds continued to tessellate to an infinite point and I felt as though I were suspended above this expanse, hanging like a figure head hangs off the bow of a ship. Throughout the trip, I remember being overcome by the profound beauty of the scene I was witnessing. If I tried to focus, I could remember that in base reality I was in a room in Johns Hopkins, but that didn't alleviate the feeling of being in an entirely separate reality, as though I were sitting in a container that cordoned me off from the 'normal' world. In summary, Oberhaus said "the experience was quite pleasant." He added: "I only had a brief moment of panic when it seemed like one of the notes in the new age soundtrack had been held for far too long. I began to worry that time was dilating and that I might be trapped in this space for eternity. When the music progressed to the next note, however, the panic quickly subsided and time resumed its normal cadence."

Oberhaus then took a higher dose the following day in an MRI machine. While the first dose of salvia in the machine didn't produce anything special, likely because it was a placebo, a very low dose, or that he had made some error during inhalation, the second dose in the machine resulted in a slightly less intense trip than the very first dose. "The reason, I think, was that the loud and persistent sounds of the MRI machine kept me tethered to the outside world and I was unable to fully immerse myself in the world that the salvia was generating," writes Oberhaus. "Still, I would describe it as a pleasant and visually striking experience."