https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3506170/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3506170/ "In individuals who are vulnerable to addiction, re

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3506170/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3506170/ "In individuals who are vulnerable to addiction, repetitive exposure to the agent induces long-lasting neuroadaptative changes that further promote drug-seeking behaviors and ultimately lead to persistent and uncontrolled patterns of use that constitute addiction. These neuroadaptive changes are the bases for tolerance, craving, and withdrawal and lead to a motivational shift.3 Motivation to drug-seeking behavior is initially driven by impulsivity and positive reward. In contrast, compulsivity and negative affect dominate the terminal stages of the pathology. Addictions are in a sense “end-stage” diagnoses because at the time diagnosis is made potentially irreversible neuroadaptative change have occurred—changes that were preventable at an early point of the trajectory of the illness." Two key things are pointed out here: 1. not everyone is vulnerable to addiction, and 2. "addiction" as understood behaviourally, is an "end-stage" diagnosis of possible irreversible neuroadaptative changes".