Tachypsychia, which means in Greek fast thought, during this symptom we have so many ideas that come quickly to mind that we start a reasoning but we do not finish it, interrupted then by another idea that comes to mind and so on…
… Each time we think that the idea we have is very important to take into account and the ideas older than two ideas back, we forget them because hidden by the new idea that comes to mind, we realize that we forget something but we do not know what, it's annoying because it was important! At least that was my feeling. The mind is invaded by ideas that fuse.
Obviously it's exhausting and I think it can manifest itself in the fact that the patient speaks a lot and very quickly.