I would gently suggest that your problem is that your mind has created this phenomenon, but it is becoming intrusive. On the other hand, you like the fact that this epiphany/ mind artifact occurs. You believe perhaps that it is a mark of special spiritual worth- are you really asking for advice on how to control its appearance, or subtly boasting about it? Symptom of illness have historically been interpreted as religious visions- schizophrenia, epilepsy, migraine. That's not to belittle them- they have often been the spur to great creativity, and I wouldn't have given Hildegard of Bingen medication to stop her visions. But you have to decide whether it's worth the bother, and seriously contemplate that a health check might be more valuable than believing you have a direct line to nirvana.