The cumulative body of research reviewed suggests chronic cigarette smoking is associated with deficiencies in auditory-verbal learning and/or memory, general intellectual abilities, visual search speeds, processing speed, cognitive flexibility, working memory and executive functions, across a wide age range. With advancing age, chronic smoking is related to abnormal decline in reasoning, memory and global cognitive function, and may increase the risk for both vascular dementia and Alzheimer’s Disease. However, several studies showed a weak or no association with smoking status and neurocognition. Chronic smoking is related to structural and biochemical abnormalities in multiple brain regions, particularly the anterior dorsolateral, mesial frontal cortex, limbic system and underlying WM. A dose-response relationship is suggested between cigarette smoking, neurocognition and neurobiological function. The reviewed literature suggests the adverse neurobiological and neurocognitive effects of chronic cigarette smoking in humans may be related to the direct and indirect consequences of continual exposure of the cardiopulmonary system, cerebrovascular system and/or brain parenchyma to the combustion products of cigarette smoke. However, the potential mechanisms contributing to the neurobiological abnormalities observed are derived from in vitro and animal
