There is a thing called lucid dream which is actually your usual dream in the REM period of your sleep but where you're as conscious (well in the best case scenario) as you re in the real life.One way is to synchronize those dreams, firstly, with the machine that is going to parse data (metrics and other stuff), secondly, if we're talking about some kind of VRMMO game - with the centralized server.

Now, the whole plan is crashing at the very first step. Putting a brain in the full-time REM sleep is kinda too unhealthy.Assuming, we're actually able to overcome the overdriving of the human brain, the "synchronization" will rather be done by intrusive methods, which is not going to be accepted by many people, if not all of them. Just imagine having some sort of connection port to your body\brain like people in The Matrix, which is going to be used every time you want to play.

And so on, too many problems arise. I may not be an expert in neuroscience or even in engineering but it seems to me like it's literally impossible.