I don't experience the effects your talking about with my mood stabilisers (valproate) but i did with my AP ( risperidone).
I would try not to worry about it too much (easier said than done i know!!!) but if you do feel as though it is becoming a problem then maybe a chat with your prescribing doctor? If it makes you feel any better i have the short term memory of an Alzheimers patient, and i'm 25!! :-( lol.