Examining Brain and Behavior in Light and Intermittent Smokers
To date, most research on cigarette smoking has focused on heavy smokers – typically those who smoke 10 or more cigarettes each day. In contrast, lighter smokers have received much less attention in the field of smoking research. This is a significant limitation, as even low-level cigarette use substantially increases the risk for serious health problems (e.g., cancer and heart disease). Furthermore, while rates of heavy smoking have declined in the past decade, rates of light daily and intermittent (or nondaily) smoking have increased dramatically, particularly among emerging adults (individuals between the ages of 18 and 25). Interestingly, some light and intermittent smokers exhibit clinically significant symptoms of nicotine dependence (e.g., nicotine withdrawal, inability to quit), while others display little or no dependence. Currently, little is known about the causes and correlates of these widely varying levels of nicotine dependence.
We are currently conducting two studies that are designed to address this knowledge gap. The first study, which is funded by a grant from the National Institute on Drug Abuse (R03DA035929), integrates standard laboratory measures with a method called ecological momentary assessment, which involves repeatedly and intensively sampling current behavior over time and in participants’ natural environment. In this case, participants are provided with a smartphone that they use to complete surveys about their experiences during daily life. The goal of the project is to identify variables (for example, aspects of personality, sensitivity to rewards) that predict individual differences in nicotine dependence and the ability to regulate cigarette use in light daily smokers (those who smoke between 1 and 5 cigarettes each day).
In the second study, we are using functional magnetic resonance imaging (fMRI) to compare brain activity during risky decision making in intermittent smokers to that of nonsmokers. One key advantage of fMRI is that it can detect subtle differences that may be very difficult or impossible to uncover using other methods (for example, by simply asking people to describe their behavior). By identifying how intermittent smokers and nonsmokers differ when they make decisions under risk, we hope to gain insight into the nature of cigarette smoking – an inherently risky behavior.