Hello,
From what i know about those kinds of testers (i use two wire testers only) they do not show an active line unless the breaker is turned 'on' (even when the tester is held outside of the Romex cable but close to the outside jacket), and the breaker usually only breaks the 'hot' wire, not the 'neutral' wire. That means they can not pick up a signal from the neutral wire, only from the hot wire if it is turned on at the breaker box.
Of course this means you would not get a reading on the neutral line even if the breaker was turned 'on'.
Also, just because you have something connected between the hot and neutral that doesnt make the neutral 'hot', it's still neutral, so you still wont get a reading even with a 100 watt bulb connected in the circuit.
You might want to mention what exactly you want to test for...what you are trying to find out here.