If you are not expecting to have your preferences changed, they probably won't be. I believe that for the study participants they explicitly recruited older, religious people with no previous psychedelic experience. People much more suggestible to the power of magic. What is more likely for you is more of a "huh, it's kind of neat that my brain also functions like this."
I think that for a rationalist to have permanently changed beliefs as a result of a psychedelic experience it would have to represent an improvement in one's rationalism or personal utility function. If you spend the trip mediating on optimizing your preferences, then you're only going to improve them. Most likely, nothing will change, but there is always the possibility that you can be more rational.
Is it rational to take psilocybin?
Just to make my definition of rational clear:
Rationality is only intelligible when in the context of a goal (whether that goal be rational or irrational). Now, if one acts rationally, given their information set, will chose the best plan-of-action towards succeeding their goal. Part of being rational is knowing which goals will maximize one’s utility function.
According to Discovery:
“Scientists released their findings on a recent survey of volunteer psilocybin users 14 months after they took the drug.”
“Sixty-four percent of the volunteers said they still felt at least a moderate increase in well-being or life satisfaction, in terms of things like feeling more creative, self-confident, flexible and optimistic. And 61 percent reported at least a moderate behavior change in what they considered positive ways.”
Assuming you won’t get a bad trip, is it rational to take the drug?
I doubt a psychedelic experience can help me optimize my current utility function better than my sober self. How can I be more rational from a drug? Therefore, I conclude that it must, in fact, change my preference ordering—make me care about things more than I would have otherwise. I prefer my preferences and therefore would rather keep my preferences the way they are now.
If you were guaranteed to have all these positive results from taking the drug, would you take it?