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Background A member of the Herpesviridae group of viruses, cytomegalovirus (CMV) has a seroprevalence of approximately 58% in the United States, although the seroprevalence varies by age and other sociodemographic factors. While prenatal infection with CMV has been associated with adverse effects on neurodevelopment, growing evidence suggests it may also be associated with alterations in cognition in adults. In addition, CMV seropositivity has been linked to several psychiatric conditions, including schizophrenia. While previous work has found CMV seropositivity associations with cognition in schizophrenia, little work has investigated its specific impact on underlying brain integrity in the illness. The overarching aim of this project was to examine the influence of CMV status on cortical integrity and behavioral functioning in samples of schizophrenia and healthy individuals both seropositive and negative for the virus. Methods Schizophrenia (SCZ = 63; 31 CMV+) and healthy control volunteers (CON = 25; 12 CMV+) with clinical, cognitive, and imaging data and available blood samples were used for the study. CMV seropositivity was established with micro-enzyme-linked immunosorbent assay (ELISA) analysis using a commercially available research kit for quantitative immunoenzymatic determination of anti-CMV IgG-class antibodies. Cognitive and clinical functioning was assessed using a standardized battery. Structural T1-weighted images were processed using the FreeSurfer toolkit v5.3.0. Analyses included ANOVA models examining differences in cortical thickness and cognition between CMV seropositive (+) and negative (-) groups per condition (SCZ and CON), within-group linear models examining the relationship between anti-CMV IgG antibody titer values and cortical thickness, and Pearson correlation models between cortical ROIs thickness and behavioral variables in SCZ. Results No significant cortical thickness differences were observed in SCZ(+) vs SCZ(-), as well as in CON(+) vs CON(-) contrast maps; however, linear modeling of IgG antibody titer values along the cortical surface revealed patterns similar to the (+/-) contrasts for each group. This included in CON = sensorimotor regions, supramarginal gyrus, insula, and medial occipital regions and in SCZ = posterior cingulate, frontal pole, and parietal association regions that survived multiple comparison correction and subsequently utilized as volumetric ROIs in Pearson models. Correlations revealed significant relationships between parietal association cortex with verbal intellect (r=0.41, p=0.003) and negative symptoms (r=-0.32, p=0.023); and posterior cingulate with disorganization (r=0.40, p=0.004) while controlling for the effects of age in all models. Discussion Contrast results revealed attenuated, but differential, patterns of cortical loss in CMV(+) subjects for each group that were supported by linear modeling of IgG antibody titer values. Most striking were abnormalities in posterior cingulate and parietal association regions in SCZ that also related to aspects of IQ and clinical symptomatology. Overall, findings suggest the effects of the CMV pathogen have a unique neurobiological expression in SCZ that may explain some features of its behavioral profile. [ABSTRACT FROM AUTHOR]

Background Abstinence from cigarette smoking is associated with disrupted interactions among the core cognitive resting state networks including the Salience (SN), Default mode (DMN) and Executive control (ECN). Unified multimodal methods [Resting state connectivity analysis, Diffusion Tensor Imaging (DTI) analysis, and cortical thickness analysis] were employed to test the hypothesis that the impact of cigarette smoking on the balance among these networks is due to alterations in white matter connectivity, functional connectivity and cortical thickness (CT) and that these metrics define fundamental differences between smokers and non-smokers. Methods Multimodal analyses of previously collected data via the Human Connectome Project were performed on 18 smokers and 18 age- and sex-matched nonsmoking controls. Resting state functional magnetic resonance imaging (fMRI) was used to compare SN-DMN and SN-ECN interactions between smokers and nonsmokers. The anatomy of these networks was then assessed using DTI and CT analyses. Finally, we computed a composite variable [resource allocation index (RAI)] that summated the combined strength of interactivity within these networks. Results Relative to control nonsmokers, resting state fMRI analysis revealed no difference in the coupling of networks. However, Resource Allocation Index computation of the inter-network coupling was significantly lower in the smokers. FA of right cingulum bundle was significantly lower in smokers as was thickness of left inferior parietal cortex, left and right precuneus, which are nodes of the ECN and DMN, respectively. Reduced RAI predicted lower cingulum bundle FA in smokers. Reduced thickness and FA were associated with degree of nicotine dependence as measured by the Fagerström score. Discussion Our results demonstrate that tobacco cigarette smoking is associated with alterations in all three independent metrics of brain function and anatomy. Whether these reductions are pre-existing, transient or permanent is not known. The observed disrupted salience in resting state networks, medial parietal thickness reductions and cingulum FA deficits may contribute to the cognitive and affective abnormalities that have been documented to occur in smokers. [ABSTRACT FROM AUTHOR]