Usefulness of EEG Techniques in Distinguishing Frontotemporal Dementia from Alzheimer’s Disease and Other Dementias

Abstract

The clinical distinction of frontotemporal dementia (FTD) and Alzheimer's disease (AD) may be difficult. In this narrative review we summarize and discuss the most relevant electroencephalography (EEG) studies which have been applied to demented patients with the aim of distinguishing the various types of cognitive impairment. EEG studies revealed that patients at an early stage of FTD or AD displayed different patterns in the cortical localization of oscillatory activity across different frequency bands and in functional connectivity. Both classical EEG spectral analysis and EEG topography analysis are able to differentiate the different dementias at group level. The combination of standardized low-resolution brain electromagnetic tomography (sLORETA) and power parameters seems to improve the sensitivity, but spectral and connectivity biomarkers able to differentiate single patients have not yet been identified. The promising EEG findings should be replicated in larger studies, but could represent an additional useful, noninvasive, and reproducible diagnostic tool for clinical practice.

Cerebrolysin in the therapy of mild cognitive impairment and dementia due to Alzheimer's disease: 30 years of clinical use

“…69,70 For instance, amyloid PiB-PET and cortical thickness in MRI were found to be more reliable biomarkers than FDG-PET for the detection of significant changes after 24 months in early AD. 70 Blood biomarkers, 71 PET imaging of synaptic density and mitochondrial function, 72,73 GAVRILOVA AND ALVAREZ | 2779 and electroencephalographic (EEG)-based markers 74 are among the most promising new biomarkers being developed.…”

Neurophysiological markers of network dysfunction in neurodegenerative diseases

“…Numerous studies have highlighted the utility of combining such resting state EEG activity and connectivity measures for differential diagnosis of neurodegenerations, particularly the dementias (Nardone et al, 2018). For example, using temporal high beta, parietal theta and alpha and high beta power, a stepwise discrimination function can distinguish AD and FTD patients with 84.6% accuracy and is highly accurate in separating controls (100%) from FTD patients (84.6%) (Yener et al, 1996).…”

Event related potentials (ERPs) and alpha waves in cognition, aging and selected dementias: A source of biomarkers and therapy

“…Cholinergic neurons i.e acetylcholinesterase (AChE)-positive neurons modulate cortical processing and responses to new and relevant stimuli. Butyrylcholinesterase (BuChE)-positive neurons play a role in attention [125][126][127]. AChE and BuChE in thalamic nuclei project diffusely to the cortex and frontal cortex respectively.…”

“…AChE and BuChE in thalamic nuclei project diffusely to the cortex and frontal cortex respectively. Cholinergic stimulation results in a shift towards faster frequencies, whereas interference with cholinergic function or a hypofunctional cholinergic system leads to an increase in slow wave activity [127]. Treatment with cholinesterase inhibitors helps inhibit acetyl and/or butyryl cholinesterases that are responsible for the breakdown of acetylcholine in the brain [125][126][127].…”

“…Cholinergic stimulation results in a shift towards faster frequencies, whereas interference with cholinergic function or a hypofunctional cholinergic system leads to an increase in slow wave activity [127]. Treatment with cholinesterase inhibitors helps inhibit acetyl and/or butyryl cholinesterases that are responsible for the breakdown of acetylcholine in the brain [125][126][127]. The power increase of alpha spectral power correlated with the modulation of butyrylcholinesterase on thalamic nuclei restoring of the cholinergic system to near physiological levels resulted in the improvement of cognitive performance [128][129][130].…”