Tobacco users will be randomized to use electronic cigarettes containing varying levels of nicotine and flavor during laboratory protocols to investigate the effects on the brain and behavior. Subjects will complete surveys, functional magnetic resonance imaging scans, and complete computerized tasks. Eligible participants include daily users of inhaled tobacco products who are at least 21 years old, able to read and write in English, and not planning to quit tobacco use within the next month. Exclusion criteria include: current substance use impairing participation, unstable or significant medical conditions, current use of smoking cessation medication, uncontrolled serious mental illness, and MRI safety or neurological contraindications.

Subjects will taste test a variety of e-cigarette flavorings, answer questions and complete a single MRI.

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