just like with drugs I fear it can trigger something in "sensitive" (or mad, as you wish) individuals that would otherwise have remained dormant... In answer to your question, AstralFae18, I have tried but not much happened, I felt my heart racing and I had the feeling my brain was moving, at some point I even felt like it was difficult not to open my eyes... but I didn't hear, see or experience anything that was very clear. I also completely lost track of time (like I thought it lasted half an hour but two hours had passed) and felt a bit shaky afterwards.
Thanks for your good advice!