Visions and flashbacks of previous lifetimes are a very common phenomenon during kundalini activity or awakened state. It is a form of spontaneous kriya which enables the kundalini infused individual to download experiences from the collective unconscious field of awareness, or Aakasha.
This can often comprise of experience of other ascended beings & golden periods from the past, all of which are stored and accessible in the akashik field. A siddha is capable of doing this willfuly, though for others the downloads and flashes are beyond their willful control. The feeling that one is a reincarnation relation is usually with the ones they resonate karmically with.
This is a sign that the person is within the process of metamorphosis and developing astrally, and the consciousness is becoming independant of instruments of sense in order to experience reality.
It’s an opportunity to release old karma, to gauge the progress and set the correct course through the path that should be taken so as to avoid the loopholes and pitfalls that were previously encountered by others with similar karma. Though some of these downloads are simply flashes unrelated to our individual process, yet insights for the collective consciousness of the race, as well as memories of past timelines during which humanity went through conscious expansion and it got registered in the akashik history of our race.
Remaining indifferent and detached to such visions is a challenge and this pitfall becomes an escape route from the self for many who unknowingly build their personality structure around such flashes. In most cases its innocence and lack of proper knowledge and guidance, though the ego starts dwelling in the past timeline and that results in loosely defined personal borders, feeling alienated in society and identity crisis. Often enactment of the past persona ,which is usually a famous being, becomes a tool for the ego to aggrandise itself and feel elect, believing it is a reincarnation of the one in their visions. The underlying reason is usually inability to deal with ones own past karma which is traumatic.
Reincarnation implies a reincarnating self. There is no such thing. The bundle of memories and hopes, called the “I”, imagines itself existing everlastingly and creates time to accommodate its false eternity. To be, I need no past or future. All experience is born of imagination; I do not imagine, so no birth or death happens to me. Only those who think themselves born can think themselves re-born. All exists in awareness, and awareness neither dies nor is re-born. It is the changeless reality itself.”
– Sri Nisargadatta Maharaj
The only real truth is happening NOW, the non dual self is beyond the impressions and experiences accumulated in the subtle field. THAT , which you truly are, is never born and never dies, reincarnation of the unmanifest is thus a contradiction. Even the manifested is uniquely destined for every individual and the only way to accomplish the earthly mission on the level relative duality is through BEING originally yourself. Being as you are.