I only took Wellbutrin XR for a fairly short time about 9 years ago. It was destabilizing for me. That's all I remember about it. The only medications that affected me cognitively were Lithium and larger doses of Lamictal. I no longer take Lithium. I do take Lamictal, but only 100 mg, which is side effect friendly for me. My Tegretol XR does make me quite clumsy, but not cognitively impaired.