It sounds like you are feeling "done" with wiping him, yes? At a time when it isn't and hasn't recently been an issue, sit down with him and say, Honey, we have problem, I'm wondering if you can help me solve it? Since he's six and knows almost everything
:, you will probably get a "yes". Say, "I know you are capable of taking care of your own toileting, but it seems like there is something about it that bothers you. Can you tell me about that?" From there, you can probably figure out a solution that works for both of you. The thing is, he, not you, owns the problem. This is a great opportunity to help him see himself as capable.
Sometimes, things like this are a way that kids express their belief that they have to be helpless to belong. NOT because you did anything wrong, but because kids are not so great at accurately evaluating situations.
This chart can really be helpful: http://ourworld.compuserve.com/homep...in/dealing.htm
Anxiety is a learned response that can be unlearned. Yes, it is chemical, but it is chemistry that an individual can influence. Even very young children can be guided to question their own decisions about the meaning of situations. Honestly, and in a friendly way, "why" can really help kids to uncover unhelpful beliefs.
I am not a fan of bribery or rewards. It puts ownership of the problem in the wrong hands, and only reinforces a child's belief that he needs to keep mom busy with him. Plus it teaches kids to get stuff (extrinsic)instead of succeed at problem-solving (intrinsic). (Overheard at school- "If we line up right, WHAT DO WE GET?" grrrrr.) Just like punishment, rewards do not address the real issue, and do little to help kids see the connection between cause and effect. JMO.