Time and time frequency domain analysis of EEG signals of mild cognitive impairment Alzheimers disease MCI AD

Abstract

Electroencephalogram (EEG) is a record of the brain electrical activity produced newlineby the neuronal population of the cortex. EEG method is widely used for the newlinediagnosis of disorders of the nervous system like brain damage, stroke, epilepsy, and newlinedementia. The current study focuses on Mild Cognitive Impairment-Alzheimer s newlinedisease (MCI-AD), the prodromal phase of AD, the fastest progressing neurological newlinedisease in the world. The clinical symptoms of AD include behavioural dysfunction, newlineintellectual as well as cognitive deficits. The abnormal electrical potentials recorded newlinefrom the scalp of the brain reflect the abnormal patterns of brain structure. Positron newlineemission tomography (PET), magnetic resonance images (MRI) and cerebrospinal newlinefluid (CSF) biomarkers are restricted for long-time assessment due to the newlineoverwhelming cost and invasive manipulation. Non-invasive and low-cost EEG newlinemethod enables to derive a biomarker with larger dynamical range. This study is an newlineattempt to characterise EEG signals of mild cognitive impairment-Alzheimer s newlinedisease (MCI-AD) patients using advanced signal processing techniques. newlineA group control study is adopted for the present analysis. The current study newlineconsidered EEG signals with Clinical Dementia Rating (CDR) value and#8804; 1 for Mild newlineCognitive Impairment Alzheimer s Disease (MCI-AD). Mini-Mental State newlineExamination (MMSE) and Addenbrooke s Cognitive Examination (ACE) are the newlineneuropsychological indices used in the study. The sampling frequency of the EEG newlinesignal considered is 400 Hz. A unipolar EEG recording from both left and right newlinelobes of the brain is carried out for data acquisition. The measuring electrodes are newlineplaced at 23 electrode locations: Fp1, Fp2, F3, F4, C3, C4, P3, P4, O1, O2, T1, T2, newlineF7, F8, T3, T4, T5, T6, Fz, Cz, Pz, A1 and A2 according to the International 10 20 newlineelectrode placement system.