Understanding Nicotine Addiction and Its Brain Reward Systems

In 1976, Professor Michael Russell cogently recognized that “People smoke for nicotine but die from the tar.”   The major health consequences from tobacco use stem not from nicotine itself but from the vehicle by which the nicotine is delivered.  Although high doses can be severely toxic, in medical dosages, products containing purified nicotine are not associated with significant adverse health effects. Three topics will be reviewed to help explain how basic brain mechanisms may play a role in both the concerns about nicotine and the promise of nicotine products as tools to reduce tobacco use:  1) the rewarding and reinforcing effects of nicotine so that repeated use of the substance is implicated in habit formation and addiction to tobacco products; 2) the importance of adolescence as a period of unique risk for development of addiction given exposure to nicotine at this stage of life; and 3) how electronic nicotine delivery systems (i.e “e-Cigarettes”) have both promise as tools to reduce use of tobacco products and concern as substances that could serve as either a gateway for the non-users of tobacco or as a dangerous crutch which perpetuates a pattern of tobacco use among current tobacco users.  The bottom line is that not enough is known about e-Cigarettes and their potential health impacts.  Additional research is currently underway and is sorely needed to inform these important public health and policy issues.