What is the scientific explanation for dreams?

What's the psychological explanation for the "falling sensation" in dreams?

• Lately I've been having a feeling when I'm asleep, where I feel like I'm falling. It feels like the part of my brain that checks whether I'm standing up balanced or not, suddenly decides that I'm not balanced on my feet and probably just tripped over something. I feel like I am falling down, though I'm laying flat on my back on the bed. What's the phenomenon behind this? Is it random firing of neurons in that part of the brain that somehow happens to stimulate this feeling? Is this vertigo? Does it mean that if I were an Inception character, I wouldn't be able to wake up from dreams?

• Answer:

  Usually I'd seen this happen to myself during that transition state from wakefulness to falling asleep. And we would be fully (or at least somewhere) aware that we are about to fall asleep. And, the falling sensation is generally accompanied by the visuals such as one walking somewhere or on steps and suddenly, we wake up with one or both the legs raised at a start in an attempt to assume the posture that restores our balance because we seem to lose it during that dream state! If that is the case, although I'm not yet well-versed with the domains of the Brain, I think your question regarding the activation of associated regions of Brain would be more relevant than any others. And, even if you were an inception character, there is no doubt that you would be pushed out of that quasi-dream state! ;) If that is not the case, and you feel that even though you want to wake up desperately from the dream, you somehow cannot, check the articles on 'Sleep Paralysis'. Now, don't be bothered about the term but its a very normal phenomenon which has a very wide range of causes, and a very active research is going on it, although there were earlier hypotheses that rendered supernatural meanings to it! To begin with a good read, check this one out, and there are further links that you can follow from there on: http://www.livescience.com/27621-sleep-paralysis-scary.html