Alterations of Coherent Theta and Gamma Network Oscillations as an Early Biomarker of Temporal Lobe Epilepsy and Alzheimer's Disease.

Valentina F Kitchigina

doi:10.3389/fnint.2018.00036

Abstract

Alzheimer’s disease (AD) and temporal lobe epilepsy (TLE) are the most common forms of neurodegenerative disorders characterized by the loss of cells and progressive irreversible alteration of cognitive functions, such as attention and memory. AD may be an important cause of epilepsy in the elderly. Early diagnosis of diseases is very important for their successful treatment. Many efforts have been done for defining new biomarkers of these diseases. Significant advances have been made in the searching of some AD and TLE reliable biomarkers, including cerebrospinal fluid and plasma measurements and glucose positron emission tomography. However, there is a great need for the biomarkers that would reflect changes of brain activity within few milliseconds to obtain information about cognitive disturbances. Successful early detection of AD and TLE requires specific biomarkers capable of distinguishing individuals with the progressing disease from ones with other pathologies that affect cognition. In this article, we review recent evidence suggesting that magnetoencephalographic recordings and coherent analysis coupled with behavioral evaluation can be a promising approach to an early detection of AD and TLE.Highlights –Data reviewed include the results of clinical and experimental studies.–Theta and gamma rhythms are disturbed in epilepsy and AD.–Common and different behavioral and oscillatory features of pathologies are compared.–Coherent analysis can be useful for an early diagnostics of diseases.

Highlights

It is known that theta and gamma oscillations are closely related to cognitive processes
Theta oscillations have been registered in the neocortex where they are pronounced in the frontal midline (Klimesch et al, 1997; Kahana et al, 1999; Jensen and Tesche, 2002; Canolty et al, 2006; Guderian et al, 2009), and in the subcortical areas (Paré et al, 2002; Magill et al, 2006; Nerad and McNaughton, 2006; DeCoteau et al, 2007; Kabanova et al, 2011)
It is known that the main problem in diagnosis of neurodegenerative diseases is the detection of neuronal abnormalities at early stages of their development

Summary

Introduction

It is known that theta and gamma oscillations are closely related to cognitive processes. We analyzed the information on some similarities and differences in these disorders, mainly in the disturbances of specific types of memory, theta and gamma rhythms and their coherence. Gamma and theta oscillations normally show a marked phase–amplitude CFC considered to be central to hippocampal functions (Tort et al, 2008, 2009; Newman et al, 2013).

Results

Conclusion