This study is designed to evaluate the success of mechanistic target engagement in two specific contexts: under standard smoking conditions and under nicotine deprivation (stress) conditions. After screening, consent, and baseline assessment, participants selected on the basis of inclusion/exclusion criteria will be randomized to one of three intervention conditions: (1) a health-education control condition (CC), (2) a mindfulness training condition (MT), or (3) a mindfulness training condition combined with training applying mindfulness skills in the context of interoceptive exposure (Mindfulness+IE). Following 6 sessions of these interventions, delivered over 3 weeks, participants will then undergo the standard smoking assessment of mechanistic targets. Two days later (and matching the progression to quit-attempt challenges following treatment), participants will undergo the deprivation window assessment (14 hours of smoking abstinence) of these same mechanistic targets, followed by evaluation of lapse behavior and smoking topography in the McKee paradigm to yield: (1) latency to initiate smoking during a monetarily reinforced delay period, (2) the number of cigarettes smoked during a subsequent 60-minute self-administration period, and (3) exploratory analysis of smoking topography: puff volume, puff duration, and inter-puff interval. Participants will be recruited to Boston University through study advertisements targeted to low SES neighborhoods, with attention to health service centers and religious institutions serving low SES individuals.

Following telephone screening for basic eligibility, participants will be scheduled for an informed consent interview and subsequent baseline assessment session. Interventions are to be completed over the subsequent 3 weeks, and post-treatment assessments of the mechanistic targets are scheduled for one-week (standard smoking assessment) and one week + 2 days (deprivation-window assessment) from the last intervention session. For the standard smoking window assessments, participants are asked to smoke .5 hour before the scheduled assessment session. The deprivation-window assessment is scheduled two days later, (for example, scheduled for 12:00 noon, with smoking to cease at 10PM the night before). Upon arrival to the lab, nicotine abstinence will be verified by expired CO levels, as determined by a cut-off of half of the participant's screening session CO concentration or \<10 PPM (those failing will be rescheduled). After verification of abstinence, participants will complete assessment of the triple-risk mechanistic target variables. These assessments will be followed by the McKee Lapse protocol: participants will be instructed that over the next 50 min, they will have the option to initiate a cigarette self-administration (smoking) session at any point or to delay initiation in exchange for monetary reinforcement. If participants choose to delay, they will be awarded funds for each 5-minute increment they are able to resist smoking. Once participants choose to end the delay period in order to smoke (or resist smoking for the entire 50 minute delay period), they will then participate in a 60-minute cigarette self-administration session, in which they will be given the choice to either smoke their preferred brand of cigarettes or receive monetary reinforcement for cigarettes not smoked. Participants will be given funds at the beginning of the self-administration session and will lose a portion of the funds for each cigarette smoked. When participants smoke in this protocol, we will use the Clinical Research Support System (CReSS) to measure smoking topography. The reliability and acceptability of use of the portable CReSS device is well documented,88,94 and is recommended over direct observation. Topography data will include puff CO volume, puff duration, and inter-puff interval. Puff level data will be averaged to compute mean topography variables for each participant.