I would say that when it comes to hero calls or marginal decisions, such as determining whether your opponent is bluffing or not, that voice inside your head is actually a result of thousands of hands of experience.  Maybe a glint in someone's eye, the way they are betting, the way the hand developed is very similar to a hand that has happened before.  Your conscious brain cannot recall it, but your subconcious mind can.

As far as the hand you are describing, I'm certain that you realize that you do not have some sort of voodoo magic.  You cannot predict the future and I think that you know that.  It's the fallacy of confirmation bias hard at work.  Let's say you have Q4 and two players are all in.  You know that logically you are crushed, but something is telling you to call.  Then the board runs out AK10J2.  OMG you would have had a royal flush!  The voice in your head was right!  Wrong!  Just because you had a thought that you would have won and you actually would have does not mean you magically predicted the result.  You are also probably forgetting or otherwise choosing to ignore all the times where you had Q4o, something told you to call, and you would have lost.  You have to be very careful with the waters you are treading on because it can lead you to results oriented thinking of the worst kind. 

BTW I'm not trying to be rude but I'm just trying to prevent you from making some of the worst mistakes you can make in poker. 

Again, it depends entirely on the situation, and what you're saying the brain is capable of.

Let's take a real life hand.  I raised from MP with 88 and got a two callers.  The board comes 965.  I cbet and get one caller.  The turn is a 9.  I don't think the turn changes anything.  If my opponent had a 9, he was ahead on the flop, and if he didn't, I'm still ahead unless he has 78 for the straight.  I check though because I don't think I can get worse to call very often.  My opponent shoves, which is a slight overbet to the pot.  All I can beat is a bluff or semibluff.  But my opponent looks at me and I get a feeling from the way he is looking at me that he isn't confident in his hand.  I think he floated with overcards and is now bluffing.  So I call and he shows A10.

So on this hand I used a combination of reason and feel to figure out that my opponent was semi-bluffing.  The look on his face is a look I've seen on other opponents when they were weak and I think the tell is reliable.  So you could say that an inner voice told me to call, but really it is a result of thousands of hands of experience.

But do I think that the brain knows a straight is going to come when you have a straight draw or that a marginal preflop hand is going to smash the flop?  I think we both know that the answer to that is no.