Lindy,
Do you mean that you know the words you want, but can't articulate them fast enough- they're kind of lost or stuck somewhere in your head sort of feeling? Or is it a fluency in your speech itself? I tend to experience the former.
I feel your pain! I think it is an executive function malfunction we're experiencing... I suspect that conversing does not flow like it used to for us because our brains are working over time compensate and it takes longer for us to find words. I have read that the word being 'on the tip of our tongues' but not making it out is fairly common in PD- we know the word(s) we want but they just don't pop into our heads and out of our mouths like they used to do. We have a loss of fluency to add to the list of what is taken away from us.
I don't know there's much to improve it other than taking gingko to try and slow it down a bit. This is a form of mild cognitive impairment that I guess we're stuck with...I hope someone else has found success with some sort of brain gym exercises - it's really a memory recall issue, so I'm thinking that if we can find some things to help with that?
One thing...you end up speaking in platitudes. I found that if I try to do that it ends up in hilarity as I always mix my metaphors. I try to avoid common sayings or adages but when they do slip out, we all end up with a chuckle.
Laughing to keep from crying,
Laura