Sometime I feel like these incident or moments I had spent before. When I visit new places which I never visited then also I feel like I had visited it before. I might have seen these things in my dream. Is this normal thing?
closed as unclear what you're asking by Hunan Rostomyan, virmaior, iphigenie, Joseph Weissman♦ May 2 '14 at 22:54
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What you describe is called déjà vu. It is a well-known (as in: frequent) phenomenon. Whether it is 'normal' or unhealthy or a symptom etc. is not something we can answer here.
Nevertheless, to ease any worries:
In a survey, Brown had concluded that approximately two-thirds of the population have had déjà vu experiences.
Do you have any false memories?
Trick question, there is no way you can know, if something has somehow gotten the status of a memory in your brain it will seem as real to you as any other memory, regardless of origin.
A similar, but widely recognised brain defect is missing memories, commonly known as forgetting. Some memories disappear partially, we remember only fractions of a whole, some disappear completely, and some seem to have disappeared until we are somehow reminded of their existence. The matter is certainly more complex than some memories simply going away while others stay. It stands to reason that we have wast amounts of memories somewhere in the realm between remembered and forgotten.
Our minds are always searching for memories that are similar to the current situation, whether it is some place we have been, something we have done or some person we have met, we expect our memories to help us. Even if it is one of those half forgotten memories, what is left of it might be useful. Sometimes what we find isn't really coherent any more, maybe all there is left is a few parameters that by coincidence match the current situation. We didn't really remember anything, we just got the sensation that there was a matching memory. This might lead to concluding that the current event has happened before, which might manifest as a false memory. Most of the time we will probably never be the wiser, but sometimes we have strong proof for the contrary, thus a memory that defies logic.
It doesn't feel right to doubt ones own memory, but it stands to reason that there is no sure way a brain can detect all of its own errors, as failing the error detection is also a possible error. Sometimes we get a hint about our own fallibility when we end up with contradicting memories, but it seems reasonable to assume that it is far more common to gain a false memory that will never be brought in doubt.