title: Measuring Cortical Connectivity in Alzheimer's Disease as a Brain Neural Network Pathology: Toward Clinical Applications.
abstract: OBJECTIVE
  The objective was to review the literature on diffusion tensor imaging as well as resting-state functional magnetic resonance imaging and electroencephalography (EEG) to unveil neuroanatomical and neurophysiological substrates of Alzheimer's disease (AD) as a brain neural network pathology affecting structural and functional cortical connectivity underlying human cognition.
  
  
  METHODS
  We reviewed papers registered in PubMed and other scientific repositories on the use of these techniques in amnesic mild cognitive impairment (MCI) and clinically mild AD dementia patients compared to cognitively intact elderly individuals (Controls).
  
  
  RESULTS
  Hundreds of peer-reviewed (cross-sectional and longitudinal) papers have shown in patients with MCI and mild AD compared to Controls (1) impairment of callosal (splenium), thalamic, and anterior-posterior white matter bundles; (2) reduced correlation of resting state blood oxygen level-dependent activity across several intrinsic brain circuits including default mode and attention-related networks; and (3) abnormal power and functional coupling of resting state cortical EEG rhythms. Clinical applications of these measures are still limited.
  
  
  CONCLUSIONS
  Structural and functional (in vivo) cortical connectivity measures represent a reliable marker of cerebral reserve capacity and should be used to predict and monitor the evolution of AD and its relative impact on cognitive domains in pre-clinical, prodromal, and dementia stages of AD.
authors.affiliation: 1Department of Psychosomatic Medicine,University of Rostock,Rostock,Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Teipel
authors.affiliation: 2DZNE,German Center for Neurodegenerative Diseases,Rostock,Germany.
authors.forename: Michel J
authors.initials: MJ
authors.lastname: Grothe
authors.affiliation: 3Center for Cognitive Neuroscience,Neuroscience and Behavioral Disorders Program,Duke-NUS Graduate Medical School,Singapore.
authors.forename: Juan
authors.initials: J
authors.lastname: Zhou
authors.affiliation: 4Division of Nuclear Medicine and Molecular Imaging,Massachusetts General Hospital,Harvard Medical School,Boston,Massachusetts.
authors.forename: Jorge
authors.initials: J
authors.lastname: Sepulcre
authors.affiliation: 2DZNE,German Center for Neurodegenerative Diseases,Rostock,Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Dyrba
authors.affiliation: 5Department of Psychiatry and Neuroradiology,TUM-NIC Neuroimaging Center,Technische Universität München,Munich,Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Sorg
authors.affiliation: 6Department of Physiology and Pharmacology "V. Erspamer",University of Rome "La Sapienza",Rome,Italy;IRCCS San Raffaele Pisana of Rome,Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Babiloni
mesh_terms: D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000473:pathology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000473:pathology*; D010100:Oxygen / Q000097:blood
chemical_list: D010100:Oxygen
keywords: Dementia diagnosis; EEG; MRI; PET; Prognosis; Treatment trials