Effects of Nicotine Reduction on Smoking Behavior in ADHD Smokers

Inclusion Criteria: * Age 18 - 40 * Smoke an average of 5-40 cigarettes per day for at least 1 year * Breath CO levels \> 8 ppm (if ≤ 8 ppm, then NicAlert Strip \> 6) * Primary diagnosis of ADHD, any subtype as assessed by the CAADID; T-Score \> 65 on one of the DSM- V relevant scales (Inattentive Symptoms, Hyperactive-Impulsive Symptoms, Total Symptoms or ADHD Index) on the Self-Report version of the CAARS; Clinician Rated ADHD-RS score \>24. * Cognitive functioning \> 80 as assessed by the KBIT-II Exclusion Criteria: * Intention to quit smoking in the next 30 days * Currently seeking treatment for smoking cessation * Currently using nicotine replacement therapies or other pharmacotherapies as cessation aid (intermittent use acceptable) * A quit attempt in the past 30 days resulting in greater than 3 days of abstinence * Using other tobacco products more than 9 days in the past 30 days * Significant unstable medical conditions (any significant change in a serious medical condition occurring during the past 3 months including cardiovascular disease, COPD, and cancer, as determined by the study physician at each site) * Significant unstable psychiatric conditions (any significant change in psychiatric symptoms during the past 3 months as determined by the study physician at each site) * Any Axis I Psychiatric Disorder as assessed by the MINI that is significantly impairing and/or would contraindicate participation in the study * Psychiatric medication changes in the past 3 months including new prescriptions, changes in dosages or discontinuation of medications * Positive toxicology screen for any of the following drugs: cocaine, opiates, methadone, benzodiazepines, barbiturates, amphetamines, methamphetamines, and PCP (Marijuana will be tested for but will not be an exclusionary criterion, participants with valid prescriptions for opiates, benzodiazepines, barbiturates, amphetamines or methadone will not be excluded, participants failing the toxicology screen will be allowed to re-screen once. These participants will need to be re-consented before being rescreened to ensure they have received adequate informed consent.) * Breath alcohol level \> 0.01 (Participants failing the breath alcohol screen will be allowed to re-screen once. These participants will need to be re-consented before being rescreened to ensure they have received adequate informed consent.) * Current diagnosis of DSM alcohol or drug use disorder (except for nicotine) * Pregnant, trying to become pregnant or breastfeeding * Smoking 'roll your own cigarettes' exclusively * Currently taking anticonvulsant medications including: Phenytoin \[Brand Name: Dilantin\], Carbamazepine \[Brand Name: Tegretol, Carbatrol, Equetro, Epitol\], Oxcarbazepine \[Brand Name: Trileptal\], Primidone \[Brand Name: Mysoline\], Phenobarbital * CO reading \>80 ppm * Systolic BP between 90 and 160 (If below 90 then asymptomatic. Participants failing for blood pressure will be allowed to re-screen once.) * Diastolic BP between 50 and 100 (If below 50 then asymptomatic. Participants failing for blood pressure will be allowed to re-screen once.) * Heart rate between 45 and 115 bpm (If below 45 then asymptomatic. Participants failing for heart rate will be allowed to re-screen once.) * Indicating any suicidal ideation in the past month or suicide attempts in the past 10 years. * Inability to independently read and comprehend the consent form and other written study materials and measures. * Having participated in a research study during the past three months in which the participant: Smoked a cigarette that was not his/her usual brand cigarette for more than one day, used any tobacco products beyond normal use for more than one day, used any nicotine replacement products or smoking cessation medications for more than one day * Any previous experience using SPECTRUM cigarettes