The single most visited post in all of the almost 7 years that I've posted medical updates at CorePsych Blog is this posting on Vyvanse Water Titration - slowly is best with any stimulant as outlined in this video.
Common Sense: Working memory imbalances don't interfere with working memory in every circumstance, they only gum up the works, like molasses in January.
One of the main reasons some of the stimulant meds don't work effectively is that they don't cover every essential neurotransmitter system necessary for efficient pre-frontal cortical communication.
This brief video breaks down an essential difference between amphetamine [AMP] and methylphenidate [MPH] stimulants. In 4 min and 50 sec I break down the serious metabolic details for those important medication matters.