Hi there and warm welcome!! Here are a couple of definitions to your question......sometimes the effects are different for different people, but when describing it it seeems to have a universal description, if that makes sense

http://en.wikipedia.org/wiki/Derealization

http://en.wikipedia.org/wiki/Depersonalization

The only thing that worked for me at the height of its nastiness is anti-psychotics........although now I have found that they are symptoms of perimenopause as well. A bit of therapy can work a treat in helping you to "cope" better with how it feels.

You take care and I hope you get a positive outcome, babe It does get better......