title: The effects of exercise on cigarette cravings and brain activation in response to smoking-related images.
abstract: BACKGROUND
  Smokers show heightened activation toward smoking-related stimuli and experience increased cravings which can precipitate smoking cessation relapse. Exercise can be effective for modulating cigarette cravings and attenuating reactivity to smoking cues, but the mechanism by which these effects occur remains uncertain.
  
  
  OBJECTIVE
  The objective of the study was to assess the effect of exercise on regional brain activation in response to smoking-related images during temporary nicotine abstinence.
  
  
  METHODS
  In a randomised crossover design, overnight abstinent smokers (n = 20) underwent an exercise (10-min moderate-intensity stationary cycling) and passive control (seating for the same duration) treatment, following 15 h of nicotine abstinence. After each treatment, participants underwent functional magnetic resonance imaging (fMRI) brain scanning while viewing a random series of blocked smoking or neutral images. Self-reported cravings were assessed at baseline, mid-, and post-treatments.
  
  
  RESULTS
  There was a significant interaction effect (treatment × time) for desire to smoke, F (2,32) = 12.5, p < 0.001, with significantly lower scores following the exercise at all time points compared with the control treatment. After both exercise and rest, significant areas of activation were found in areas of the limbic lobe and in areas associated with visual attention in response to smoking-related stimuli. Smokers showed increased activation to smoking images in areas associated with primary and secondary visual processing following rest, but not following a session of exercise.
  
  
  CONCLUSIONS
  The study shows differing activation towards smoking images following exercise compared to a control treatment and may point to a neuro-cognitive process following exercise that mediates effects on cigarette cravings.
authors.affiliation: Tobacco Research and Intervention Program, Moffitt Cancer Center, 4115 E. Fowler Avenue, Tampa, FL 33617, USA. kate.jansevanrensburg@moffitt.org
authors.forename: Kate
authors.initials: K
authors.lastname: Janse Van Rensburg
authors.forename: Adrian
authors.initials: A
authors.lastname: Taylor
authors.forename: Abdelmalek
authors.initials: A
authors.lastname: Benattayallah
authors.forename: Tim
authors.initials: T
authors.lastname: Hodgson
mesh_terms: D001921:Brain / Q000378:metabolism*; D003071:Cognition; D018592:Cross-Over Studies; D003463:Cues; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D012907:Smoking / Q000523:psychology*