Neural Basis of Eating Behavior in Abstinent Smokers
Condition: Nicotine Use Disorder
MeSH terms: Tobacco Use Disorder
Study type: Interventional

Summary: 
      The purpose of this research study is to better understand why people gain weight when they
      quit smoking by examining food intake and changes in brain activity in smokers when they are
      smoking as usual compared to when they have been deprived of cigarettes (i.e., have not
      smoked for 4 days) as compared to a non-smoker control group.
    

Detailed description: 
      Tobacco use and obesity are the two leading causes of preventable deaths. Because these two
      behaviors share common brain reward mechanisms, reducing one behavior often leads to
      increases in the other behavior. Behavioral Economic and Incentive Salience models shed much
      light on this clinical problem. Smoking cessation produces reward dysregulation that can
      alter the motivational salience of other reinforcers, particularly food. After stopping
      smoking, smokers increase between-meal snacking, especially foods high in fat and sugar.
      Increases in caloric intake occur within days of quitting smoking, and are clinically
      significant. The investigators have also shown that smoking cessation produces working memory
      deficits and reduces activity in the brain's cognitive control circuits, making it even more
      difficult to exert self-control over temptations to eat highly rewarding foods. Thus, smokers
      have a double challenge: food becomes more salient and reinforcing at a time when their
      neurocognitive resources are compromised.

      Neuroimaging can identify mechanisms underlying behavior change beyond self-report and
      behavioral measures. The proposed functional magnetic resonance imaging (fMRI) study breaks
      new ground by integrating concepts and tools from the fields of behavioral economics and
      cognitive neuroscience to accelerate the study of mechanisms underlying PCWG. The
      investigators will use a previously validated within-subject crossover neuroimaging study
      design to examine changes in working memory, food salience (cue-induced craving), and food
      reinforcement processes in the brain after 4 days of smoking cessation (vs. smoking as
      usual). A non-smoker control group will provide insight into baseline differences from
      smokers (abstinent and satiated). Caloric intake, the primary outcome, will be assessed using
      24-hr. food recalls during each study period. The investigators will assess three parallel
      pathways including: working memory, food cue reactivity, and food reinforcement at the neural
      and behavioral levels.

      This study will provide new insights about how the brain can constrain or promote the ability
      of smokers to prevent post cessation weight gain (PCWG) and lead to new interventions that
      integrate neural and behavioral framework. Support for our predictions would inform testing
      of novel approaches to prevent PCWG, such as computerized neurocognitive exercise training to
      increase DLPFC activity and shift activity away from reward sensitive brain networks.
    

Intervention name(s): Practice Quit Attempt
Intervention type(s): Other
Intervention description(s): Smokers will be studied under 2 conditions: smoking as usual and during a 4 day practice quit attempt.
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Intervention model description: This is a within-subject cross-over neuroimaging investigation of 3 potential neural mechanisms of increased caloric intake during initial smoking cessation. Eighty smokers will be scanned on 2 occasions: (1) after 4 days of monitored abstinence (biochemically verified), and (2) after 4 days of smoking as usual (order counterbalanced). In addition, 30 healthy non-smokers (matched for sex, age, and education) will complete one period of the study to serve as a baseline comparison group.
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Nicotine Addiction; Quitting Smoking