Retarded speech (retarded meaning difficult or stunted, not a low IQ) is often a symptom of severe depression. It also is associated with high levels of anxiety, especially the fast/slow talking part. It also is associated with ADD.
Address these issues significantly and you will see your excessive emotions or lack of focus come back to more normal levels and it will naturally be much easier to think and speak clearly. I had this problem majorly my whole life until meds. For me, a very low dose of adderall solved it 50%. This amount felt more like 10000% considering I had never thought there was any hope for helping with this issue. When I tried this med it was like a light bulb turned on and it was suddenly exponentially easier, essentially effortless comparatively, to communicate my thoughts effectively. The depression and anxiety I still had in force, (I eventually realized this despite denying it for a long time because of how much more confident and happy I felt that I could finally communicate what I was thinking without torturing myself) once also treated, improved this problem another 45% or so.
Unfortunately the adderall does add quite a good deal to my anxiety and creates a not too small host of problems in its own right which I am still seeking to work around. However, the issue of my being unable to communicate what I was thinking due to an inability to formulate words/sentences well made me feel like I was being completely robbed of my individuality. People just couldnt get to know me at all. This was a huge contributer to my feelings of seriously considering and coming close to suicide. Now I still have major depressive issues to deal with and some additional anxiety issues but I have not been dangerously suicidal (which I was nearly every day of my life before adderall) one time since starting adderall. I could never k1ll myself because I have lost my brother at the age of 6 and I saw how it almost killed me and everyone else in my family. If I killed myself I understand the pain (and possible death by subsequent suicide) it would bring my family. Despite wanting more than anything to stop my own pain I could not do that to my family.
I also will say that there is a possibility that it is adderall's amphetamine content or its other neurological action that is truly responsible for this improvement in suicidality risk for me. It would be foolish for me to say that all adderall does is make it so I can talk more effectively and that alone is what has led to its helping me. The fact is adderall has lots of other pharmacological action and perhaps it is this which truly accounts for this improvement. Alternately maybe the amphetamine confidence boost (amphetamine being an ingredient in adderall) is largely directly responsible for my ability to communicate with less effort. Whatever the case, I am sure it saved my life, at least until I could get on true anti depressants. It is also worth noting that I only take 5mg IR adderall every 5 hours in order to acheive such a huge change in myself. In fact if I take even a little more l I get way too moody/emotionally flat/irritable.