There is a lot of new research on how the brain works and some of it may explain why addicts have difficulty stopping taking drugs or behave in ways they know are wrong afterwards. In some cases, their impulse control may simply be temporarily disrupted by these changes in the brain.
Below we have gathered some links and videos that may be valuable in understanding youth/adults and addiction.
http://www.youtube.com/watch?v=9pBUE5SuJnc