Alterations of Effective Connectivity Patterns in Mild Cognitive Impairment: An MEG Study
| Autor: | Alberto Fernández, Saúl J. Ruiz-Gómez, Jesús Poza, Javier Gomez-Pilar, Celia Juan-Cruz, Carlos Gómez, Roberto Hornero, María García, Pablo Núñez |
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| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Male medicine.medical_specialty Rest Alpha (ethology) Audiology Sensitivity and Specificity 03 medical and health sciences 0302 clinical medicine Neuroimaging Granger causality Neural Pathways medicine Disconnection syndrome Dementia Coherence (signal processing) Humans Cognitive Dysfunction Beta (finance) Aged Brain Mapping medicine.diagnostic_test business.industry General Neuroscience Brain Magnetoencephalography General Medicine medicine.disease Psychiatry and Mental health Clinical Psychology 030104 developmental biology Female Geriatrics and Gerontology business 030217 neurology & neurosurgery |
| Zdroj: | Journal of Alzheimer's disease : JAD. 65(3) |
| ISSN: | 1875-8908 |
| Popis: | Neuroimaging techniques have demonstrated over the years their ability to characterize the brain abnormalities associated with different neurodegenerative diseases. Among all these techniques, magnetoencephalography (MEG) stands out by its high temporal resolution and noninvasiveness. The aim of the present study is to explore the coupling patterns of resting-state MEG activity in subjects with mild cognitive impairment (MCI). To achieve this goal, five minutes of spontaneous MEG activity were acquired with a 148-channel whole-head magnetometer from 18 MCI patients and 26 healthy controls. Inter-channel relationships were investigated by means of two complementary coupling measures: coherence and Granger causality. Coherence is a classical method of functional connectivity, while Granger causality quantifies effective (or causal) connectivity. Both measures were calculated in the five conventional frequency bands: delta (δ, 1-4 Hz), theta (θ, 4-8 Hz), alpha (α, 8-13 Hz), beta (β, 13-30 Hz), and gamma (γ, 30-45 Hz). Our results showed that connectivity values were lower for MCI patients than for controls in all frequency bands. However, only Granger causality revealed statistically significant differences between groups (p-values < 0.05, FDR corrected Mann-Whitney U-test), mainly in the beta band. Our results support the role of MCI as a disconnection syndrome, which elicits early alterations in effective connectivity patterns. These findings can be helpful to identify the neural substrates involved in prodromal stages of dementia. |
| Databáze: | OpenAIRE |
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