I'm not sure about this. I'm a big guy, I barely feel 100 ug, if I didn't know what LSD was like I could easily not notice

This was intravenous though, so I’d assume the effect to be much stronger than when taken oral.

Are you sure you have really taken 100ug? The blotters these days are very often quite a bit less, although marketed as 100ug. 100ug should be enough for most for a good trip.

The placebo here was saline (no physiological effect). Sometimes they give amphetamines as a placebo so the control group also feel that something is different. But I’d expect that to affect RL hyperparameters too.