I've only taken Dexedrine once in my life and it seemed from a first timer's perspective to basically be the same thing as Vyvanse only Vyvanse is a much slower releasing medication. I've taken Adderall XR for god knows how long. Has anyone switched to either Vyvanse or Dexedrine from Adderall/Adderall XR and noticed their memory capacity has decreased ALOT? It's the only side effect that has kept me looming over XR because being in school I simply cannot afford to forget information I've spent hours trying to memorize.