ADHD 1 Adult 1 Attention 1 Attention Deficit Disorder with Hyperactivity 1 Central Nervous System Stimulants 1 Cognition 1 Dose-Response Relationship, Drug 1 Double-Blind Method 1 Female 1 Humans 1 Impulsive Behavior 1 Lobeline 1 Male 1 Memory, Short-Term 1 Methylphenidate 1 Nicotinic Agonists 1 Treatment Outcome 1 adult 1 attention 1 attention deficit disorder 1 central stimulant agent 1 cognition 1 dose response 1 double blind procedure 1 drug effect 1 female 1 human 1 impulsiveness 1 lobeline male 1