Neal and Rumple sharing a body

When Rumplestiltskin is in control, he is very aware of Neal's presence in his head, but when Neal takes over their shared body, he has no idea his father is alive, or even that they are sharing a body. When Neal first hears that Rumple might be alive, he was shocked. We know he doesn't remember because of the curse, but shouldn't he have heard Rumple's voice or felt his presence. Why doesn't Neal know about Rumple? Does Rumple just hide himself while Neal is in control? Please help.