Cue-elicited neural activity and functional connectivity among smokers associated with the decision to smoke

Open Access
Author:
Henry, Shannon Lee
Graduate Program:
Psychology
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
September 12, 2014
Committee Members:
  • Stephen Jeffrey Wilson, Thesis Advisor
  • Frank Gerard Hillary, Thesis Advisor
  • Rick Owen Gilmore, Thesis Advisor
Keywords:
  • smoking
  • cue-reactivity
  • dual systems
  • fMRI
  • uSEM
  • insula
Abstract:
Cue-reactivity, or the responses of drug users to drug cues, has been shown to be related to smoking behavior including relapse in smokers, but the mechanisms linking drug use to drug cues remain unclear. Dual systems approaches, which implicate the cognitive control system and the reward/affective system in contributing to addictive behavior, have been used in attempts to explain addictive behavior, and in particular may be used elucidate the relationship between drug cues and drug use. However, differing models have been proposed to explain the ways the dual systems may act or interact to contribute to drug use. The present study aimed to clarify this question by using uSEM on fMRI data to identify connectivity models in two groups of smokers as they were exposed to smoking (and neutral) cues and offered an opportunity to smoke, within 24 hours of initiating a quit attempt. The two groups modeled were: 1) the subjects who chose to smoke (n=19); 2) a matched sample of subjects who chose not to smoke (n=19). Results showed that smokers who were able to resist smoking displayed increased connectivity between networks, namely between the DLPFC and left anterior insula. This finding, along with past research, indicates that smokers who are able to remain abstinent may be engaging in top-down control of the feeling of smoking urge induced by smoking cues via representations of interoceptive smoking effects.