The effects of prenatal and adolescent exposure to cigarette smoke on auditory and visual attention have also been evaluated using fMRI188. Similar to the cohort described above, this study had adolescents with and without PEMCS who were and were not currently smoking. Performance accuracy was found to be impaired in the group with PEMCS compared to controls. Within the PEMCS group, males demonstrated greater reductions in performance accuracy during auditory conditions relative to visual conditions, while exposed females had reduced performance accuracy during both auditory and visual attention testing. Activation of the right superior temporal gyrus on fMRI was found to be significantly greater during auditory testing in all exposure groups relative to subjects with neither prenatal nor adolescent exposure. Activation of bilateral lingual gyri was significantly greater in the group with prenatal exposure alone than with subjects who had neither prenatal nor adolescent exposure. Intact cortical cholinergic transmission is required for normal attentional performance198. Enhanced cholinergic neurotransmission improves the selectivity of perceptual processing and improves the efficacy of brain regions supporting higher cortical function, an effect associated with reduced
