Impulsivity underlies some types of ADHD, as well as substance abuse. In addition to the direct challenges associated with attention-deficit/ hyperactivity disorder (ADHD), there is ample evidence linking it with elevated rates of substance abuse, and several recent studies add to the growing body of research on the topic - See more at: http://www.chadd.org/Understanding-ADHD/About-ADHD/ADHD-in-the-News/2015-Archive/ADHD-in-the-News-11-17-15.aspx#sthash.oHmA2V1m.dpuf