Cigarette smoking and cognitive performance in healthy Swedish adults.

BACKGROUND The relationship between cigarette smoking and cognitive function was examined in healthy Swedish adults who were participants in the Betula Prospective Cohort Study of Aging, Memory, and Health. SUBJECTS The data are from those individuals in the Betula study who were self-reported continuous smokers contrasted to those who reported never smoking cigarettes. DESIGN The dependent variables were cognitive tasks that varied with respect to difficulty and the demand they placed on processing resources. RESULTS Current smokers performed more poorly than never smokers on the more cognitively demanding tasks; namely, Block Design and free recall. CONCLUSIONS The findings were interpreted in the light of the assumption that cigarette smoking may exert its greatest deleterious effect on those cognitive tasks that place the heaviest demands on processing resources.