It has been my experience that my T's are very willing to make changes and adjustments in ways that will help me, and they appreciate the feedback. Part of your job as the client is to let them know what they can do to help you better. This doesn't have to be a big confrontation, and it might be easiest to start the session with it rather than leave it for when it's happening. Sometimes it is easier to talk about something in the abstract rather than leave it to happen again, and then mention it.

You could start out your session by saying "hey, T, sometimes I feel like I don't get a chance to finish my sentence or my thought before you respond, and I feel cut off."

In some cultures (like my loud Jewish one), interrupting is considered the norm and is considered a compliment to the speaker, that they have triggered an idea within you so profound that you must say it right away.

Actually, that is a bit of an overstatement, but it just means that some people don't intend to interrupt, their sense of this is just different than yours. The point is that you feel interrupted, and it is interfering with what you want out of therapy, and your T won't know unless you actually say something.

I have the opposite reaction in T-- my T leaves silences too open and it gives me anxious fits. So I said, don't leave so much silence after I say something (I'd like him to interrupt, basically). Cool thing is, he got it and now there's the perfect amount of time between me finishing my sentence and him talking back with me. I also think that sometimes I'm a little more tolerant of silences and will talk about what's in my head a little more, and that seems like a good thing too.