As expected, these variables converged onto a common topography of cognitive impairment, which consisted of relative decreased nAChR binding in frontal, temporal, fusiform, inferior parietal, thalamus and motor cortices, and relative preserved/increased nAChR uptake in cingulate, insula, precuneus, cuneus/calcarine and hippocampus/parahippocampus. The gene discussed is CHRNA4; the disease is Cognitive impairment.