TY - JOUR T1 - Intranetwork and internetwork connectivity in patients with Alzheimer disease and the association with cerebrospinal fluid biomarker levels JF - Journal of Psychiatry and Neuroscience JO - J Psychiatry Neurosci SP - 366 LP - 377 DO - 10.1503/jpn.160190 VL - 42 IS - 6 AU - Marina Weiler AU - Brunno Machado de Campos AU - Camila Vieira de Ligo Teixeira AU - Raphael Fernandes Casseb AU - Ana Flávia Mac Knight Carletti-Cassani AU - Jéssica Elias Vicentini AU - Thamires Naela Cardoso Magalhães AU - Leda Leme Talib AU - Orestes Vicente Forlenza AU - Marcio Luiz Figueredo Balthazar Y1 - 2017/11/01 UR - http://jpn.ca/content/42/6/366.abstract N2 - Background: In the last decade, many studies have reported abnormal connectivity within the default mode network (DMN) in patients with Alzheimer disease. Few studies, however, have investigated other networks and their association with pathophysiological proteins obtained from cerebrospinal fluid (CSF).Methods: We performed 3 T imaging in patients with mild Alzheimer disease, patients with amnestic mild cognitive impairment (aMCI) and healthy controls, and we collected CSF samples from the patients with aMCI and mild Alzheimer disease. We analyzed 57 regions from 8 networks. Additionally, we performed correlation tests to investigate possible associations between the networks’ functional connectivity and the protein levels obtained from the CSF of patients with aMCI and Alzheimer disease.Results: Our sample included 41 patients with Alzheimer disease, 35 with aMCI and 48 controls. We found that the main connectivity abnormalities in those with Alzheimer disease occurred between the DMN and task-positive networks: these patients presented not only a decreased anticorrelation between some regions, but also an inversion of the correlation signal (positive correlation instead of anti-correlation). Those with aMCI did not present statistically different connectivity from patients with Alzheimer disease or controls. Abnormal levels of CSF proteins were associated with functional disconnectivity between several regions in both the aMCI and mild Alzheimer disease groups, extending well beyond the DMN or temporal areas.Limitations: The presented data are cross-sectional in nature, and our findings are dependent on the choice of seed regions used.Conclusion: We found that the main functional connectivity abnormalities occur between the DMN and task-positive networks and that the pathological levels of CSF biomarkers correlate with functional connectivity disruption in patients with Alzheimer disease. ER -