I know this is true for me, and I know it's especially true for my husband (who has ADD.) But, once I get an idea that I want to do something, I have this very extremely high pressure drive that it has to happen now. (My husband even more so that if it doesn't happen now, then he gets very irritable about it.) It's an extremely hard emotion to fight against. It feels a lot like pressured speach to me.

I think a lot of people feel this when excited. But, I think for me (and my husband more so,) it's a feeling that is so overwhelming that it's hard for us to combat against it. It can easily push me into mania. Being excited about something does that to me. So, maybe it's something like that.