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O1–03–06: Consistency of Resting State Networks across healthy subjects measured with FMRI
Author(s) -
Damoiseaux Jessica S.,
Rombouts Serge A.R.B.,
Barkhof Frederik,
Scheltens Philip,
Stam Cornelis J.,
Smith Stephen M.,
Beckmann Christian F.
Publication year - 2006
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1016/j.jalz.2006.05.049
Subject(s) - resting state fmri , default mode network , psychology , precuneus , brain activity and meditation , consistency (knowledge bases) , brain mapping , functional magnetic resonance imaging , functional connectivity , neuroscience , pattern recognition (psychology) , audiology , artificial intelligence , cognitive psychology , computer science , electroencephalography , medicine
AD from normal aging. The goal was to determine if DTI improved identification of MCI and AD from normal aging. Objectives: We hypothesized: 1) MCI and AD are associated with reduced fractional anisotropy (FA) in the cingulum fibers; 2) DTI improves classification of AD and MCI from healthy aging when used with hippocampal volume. Methods: 17 AD patients (age: 77.1 8.8 yrs; MMSE: 22.1 4.0), 17 MCI (age: 73.1 7.4 yrs; MMSE: 27.9 2.0), and 16 cognitive normal (CN) subjects (age: 69.9 8.3 yrs; MMSE: 29.8 0.4) had MRI and DTI. Hippocampal volumes (HV) were measured using semi-automated software. DTI data were processed by tracing cingulum fibers connecting the hippocampus and posterior cingulate cortex and computing fractional anisotropy (FA). Diagnostic values of HV and FA were compared by logistic regression and a receiver operator characteristics analysis (ROC), including cross-validation of the area under the ROC curve (AUC). Results: HV was markedly reduced in AD (p 0.05) compared to CN. In contrast to HV, FA of the cingulum fibers was reduced (p 0.01) in MCI and even more in AD (p 0.001). Furthermore, the reductions were more prominent on the left side than on the right side (p 0.08) in MCI. HV alone could not reliably separate MCI from CN subjects (p 0.07), but the addition of FA in the posterior cingulate improved classification (p 0.007). HV reliably separated AD patients from CN subjects (p 0.01), as expected; the addition of FA improved the classification further (p 0.007). See table for summary; AUC is listed including 95% confidence intervals. Conclusion: Measuring FA of the cingulum fibers improves identification of MCI and may be a sensitive indicator of early AD pathology. Prospective studies are underway to determine if DTI predicts cognitive decline and conversion to AD.