Disturbed Beta Band Functional Connectivity in Patients With Mild Cognitive Impairment: An MEG Study

Mild cognitive impairment (MCI) refers to the clinical state of subjects who suffer from some degree of cognitive deterioration but do not meet clinical criteria for dementia. The aim of this study was to analyze the magnetoencephalogram (MEG) background activity in MCI subjects using two connectivity measures: coherence and synchronization likelihood (SL). Our results showed that coherence and SL mean values were lower in the MCI group than in control group at all frequency bands (delta, theta, alpha-1, alpha-2, beta, and gamma). Significant differences were found in the beta frequency band with both measures (p Lt 0.05, Mann-Whitney U-test). Coherence analysis also revealed significant differences between controls and MCIs in the gamma band. Additionally, coherence and SL mean values at each frequency band were analyzed by means of receiver operating characteristic curves. The highest accuracy (69.8%) was achieved in the beta band with both connectivity measures. Our results suggest that spontaneous MEG rhythms show disconnection problems in MCI, especially in the beta band. In conclusion, both coherence and SL may be useful measures for discriminating MCI patients from control subjects.

[1]  E. Tangalos,et al.  CME Practice parameter: , 2022 .

[2]  R. Petersen.  Mild cognitive impairment as a diagnostic entity , 2004, Journal of internal medicine.

[3]  D. Tucker,et al.  EEG coherency II: experimental comparisons of multiple measures , 1999, Clinical Neurophysiology.

[4]  M. Hallett,et al.  Identifying true brain interaction from EEG data using the imaginary part of coherency , 2004, Clinical Neurophysiology.

[5]  D. Tucker,et al.  EEG coherency. I: Statistics, reference electrode, volume conduction, Laplacians, cortical imaging, and interpretation at multiple scales. , 1997, Electroencephalography and clinical neurophysiology.

[6]  Francesco Rundo,et al.  Fronto-parietal coupling of brain rhythms in mild cognitive impairment: A multicentric EEG study , 2006, Brain Research Bulletin.

[7]  E. John,et al.  Decreased EEG synchronization in Alzheimer’s disease and mild cognitive impairment , 2005, Neurobiology of Aging.

[8]  T Dierks,et al.  Discrimination of Alzheimer's disease and mild cognitive impairment by equivalent EEG sources: a cross-sectional and longitudinal study , 2000, Clinical Neurophysiology.

[9]  Cornelis J. Stam,et al.  Magnetoencephalographic evaluation of resting-state functional connectivity in Alzheimer's disease , 2006, NeuroImage.

[10]  Jaeseung Jeong.  EEG dynamics in patients with Alzheimer's disease , 2004, Clinical Neurophysiology.

[11]  C. Stam,et al.  EEG synchronization in mild cognitive impairment and Alzheimer's disease , 2003, Acta neurologica Scandinavica.

[12]  E. Tangalos,et al.  Mild Cognitive Impairment Clinical Characterization and Outcome , 1999 .

[13]  F. Collette,et al.  Alzheimer' Disease as a Disconnection Syndrome? , 2003, Neuropsychology Review.

[14]  Massimo Buscema,et al.  Is it possible to automatically distinguish resting EEG data of normal elderly vs. mild cognitive impairment subjects with high degree of accuracy? , 2008, Clinical Neurophysiology.

[15]  Paolo Maria Rossini,et al.  Cerebrovascular disease and hippocampal atrophy are differently linked to functional coupling of brain areas: an EEG coherence study in MCI subjects. , 2008, Journal of Alzheimer's disease : JAD.

[16]  R. Petersen.  MILD COGNITIVE IMPAIRMENT , 2004, Lancet.

[17]  Jyrki Ahveninen,et al.  Source estimation of spontaneous MEG oscillations in mild cognitive impairment , 2006, Neuroscience Letters.

[18]  Francesco Rundo,et al.  Directionality of EEG synchronization in Alzheimer's disease subjects , 2009, Neurobiology of Aging.

[19]  C. J. Stam,et al.  Functional connectivity patterns of human magnetoencephalographic recordings: a ‘small-world’ network? , 2004, Neuroscience Letters.

[20]  Claudio Babiloni,et al.  Abnormal fronto‐parietal coupling of brain rhythms in mild Alzheimer's disease: a multicentric EEG study , 2004, The European journal of neuroscience.

[21]  J. G. van Dijk,et al.  Memory activation enhances EEG abnormality in mild cognitive impairment , 2007, Neurobiology of Aging.

[22]  C. Stam,et al.  Nonlinear synchronization in EEG and whole‐head MEG recordings of healthy subjects , 2003, Human brain mapping.

[23]  A. Nordberg,et al.  Quantitative electroencephalography in mild cognitive impairment: longitudinal changes and possible prediction of Alzheimer’s disease , 2000, Neurobiology of Aging.

[24]  P. Scheltens,et al.  Mild cognitive impairment (MCI) in medical practice: a critical review of the concept and new diagnostic procedure. Report of the MCI Working Group of the European Consortium on Alzheimer’s Disease , 2006, Journal of Neurology, Neurosurgery & Psychiatry.

[25]  B. Reisberg,et al.  The GDS/FAST Staging System , 1997, International Psychogeriatrics.

[26]  S. Folstein,et al.  "Mini-mental state". A practical method for grading the cognitive state of patients for the clinician. , 1975, Journal of psychiatric research.

[27]  Roberto Hornero,et al.  MEG spectral profile in Alzheimer's disease and mild cognitive impairment , 2006, Clinical Neurophysiology.

[28]  E Püregger,et al.  Magnetoencephalographic—Features related to mild cognitive impairment , 2003, NeuroImage.

[29]  J. Gore,et al.  Mutual information analysis of the EEG in patients with Alzheimer's disease , 2001, Clinical Neurophysiology.

[30]  S. Weiss,et al.  EEG coherence within the 13–18 Hz band as a correlate of a distinct lexical organisation of concrete and abstract nouns in humans , 1996, Neuroscience Letters.

[31]  F. Takens.  Detecting strange attractors in turbulence , 1981 .

[32]  R. Ilmoniemi,et al.  Magnetoencephalography-theory, instrumentation, and applications to noninvasive studies of the working human brain , 1993 .

[33]  C. Babiloni,et al.  Conversion from mild cognitive impairment to Alzheimer’s disease is predicted by sources and coherence of brain electroencephalography rhythms , 2006, Neuroscience.

[34]  Theiler,et al.  Spurious dimension from correlation algorithms applied to limited time-series data. , 1986, Physical review. A, General physics.

[35]  V. Leirer,et al.  Development and validation of a geriatric depression screening scale: a preliminary report. , 1982, Journal of psychiatric research.

[36]  Edward J Golob,et al.  Auditory event-related potentials during target detection are abnormal in mild cognitive impairment , 2002, Clinical Neurophysiology.

[37]  C. J. Stam,et al.  EEG synchronization likelihood in mild cognitive impairment and Alzheimer's disease during a working memory task , 2004, Clinical Neurophysiology.

[38]  Claudio Babiloni,et al.  White matter vascular lesions are related to parietal‐to‐frontal coupling of EEG rhythms in mild cognitive impairment , 2008, Human brain mapping.

[39]  J. Morris,et al.  Current concepts in mild cognitive impairment. , 2001, Archives of neurology.

[40]  C. Stam,et al.  Synchronization likelihood: an unbiased measure of generalized synchronization in multivariate data sets , 2002 .

[41]  Cornelis J. Stam,et al.  Synchronization likelihood with explicit time-frequency priors , 2006, NeuroImage.

[42]  C. White,et al.  The role of cortical connectivity in Alzheimer's disease pathogenesis: A review and model system , 1993, Neurobiology of Aging.