It doesnt cause psychosis. Where did you get this info from? Tv? Music? Social media? Are you saying that because some people experience more than physical reality in meditation? If you havent got psychosis then what are you worrying about? Why are worrying about it? Why let this fear stop you from being with yourself? Meditation can change your life and teach you to live in the present moment rather than worry about an event in the future that you’re not sure is gonna happen. Your thoughts bring your reality to you and if you focus on negatives it’ll come to you in time. Its easier to manifest positive outcomes cause the energy is high vibrational which means more free flowing than sluggish negative low vibrational energy