A helpful concept from Thomas Keating is "the evacuation of the unconscious". The idea is that it is normal to have painful thoughts arise into our consciousne

A helpful concept from Thomas Keating is "the evacuation of the unconscious". The idea is that it is normal to have painful thoughts arise into our consciousness when we enter into meditation. It is common in ordinary life to get into the habit of filling one's life with noise and distraction, in order to keep sources of anxiety or other negative emotions at bay. Meditation lessens the noise and distraction, which has the natural effect of making room for the suppressed thoughts and emotions to pop up. In meditation practice one learns to gently refrain from engaging with emotionally charged material, noticing it with objectivity and detachment, letting it pass by, and returning to a state of calm wordless awareness. In the natural course of events, suppressed fears and anxieties are much less powerful when looked at consciously and rationally. One ends up taking them less seriously, and consequently they tend to lessen in terms of their ability to cause unhappiness. Circling back to the point of the OP, if an attempt at meditation practice starts causing psychotic episodes or anything of that nature, don't do it. That's just common sense.