What does this sentence mean? describe it for

in the absence of contact with the real world, the human imagination can produce a distorted perception of reality.

Say you were kidnapped at a very young age and the only version of the world was from the descriptions or the things the kidnapper tells you. Your mind will use those descriptions to make up its own world and it becomes your own reality. When you are finally released you will soon realize that your version of the real world is very different than the actual thing. 

When not around humanity, the imaginative banks of the human brain may say things about the "outside world" that may be wrong or distorted. When this perception of the real world is messed up, then most people won't want to leave the place they have been in for years because they may think it is "scary" or "vicious" for various reasons...

I hope that answers your questions well enough. I may be new to this website but I work on 12th grade stuff instead of 7th like I should.

Iwould say d but idk hope this !