[thisisforyou]

> "So if I am reading this right, LSD reduced fearful reactions. I initially mis-read it as a correlation between LSD and fear."

Not really, the results were a bit more subtle and technical than that. They just found that there was a (fairly small) negative correlation on left amygdalar BOLD signal in the active group. They did not measure subjective fear, nor did they make any explicit claims about it. Just because blood oxygen levels changed does not mean the participants necessarily experienced less fear or anything different from the placebo group (in terms of fear at least).

The authors also mention toward the end of the paper that this was a fairly small dose, and that larger doses would likely induce more anxiety than placebo:

"Third, we can only provide data about one moderate dose. Higher doses of psychedelics are possibly difficult to use with fMRI, because they are more likely to induce anxiety,45 although the overall effects are still described as positive in the higher doses investigated.2, 45 The observed anxiolytic effect probably also depends on personal and environmental factors and might thus be different in the mentally ill or in uncontrolled settings."