slow down swallow take a breath and think of these actions while doing them and not how youll answer the question   give your mind time to process the question start with an easy concept in the answer and talk to it as if youre teaching them the answer your brain is going to come along in this journey just fine and will supply the proper words   dont look at the person questioning you if this causes anxiety    concentrate on your speech patterns concentrate on forming your sounds correctly   in my wheelhouse i dont have problems talking about things that interest me i have problems not talking about them so to me it sounds a lot like anxiety   that being said you also may be learning things superficially by book and not by doing  learning be book is tenuous and wont retain unless you practice it   for example you can shout all the pchem you want at me but when i can see it in practice using a lc and defining how the substrate around it affects it and changing knobs to see its dipriotic effects then i know it this is a poorly simplified overly complex example but it is taking theory into practice   thats what makes my adhd brain happy thats what makes me able to do what i do   taking a book and trying to spout back its info is like removing a hdd from one computer and putting it in another and breaking all the links and pointers