Subclinical epileptiform discharges in Alzheimer's disease are associated with increased hippocampal blood flow.

Background: In epilepsy, the ictal phase leads to cerebral hyperperfusion while hypoperfusion is present in the interictal phases. Patients with Alzheimer's disease (AD) have an increased prevalence of epileptiform discharges and a study using intracranial electrodes have shown that these are very frequent in the hippocampus. However, it is not known whether there is an association between hippocampal hyperexcitability and regional cerebral blood flow (rCBF).

Neurofilament light chain levels in serum among a large mixed memory clinic cohort: Confounders and diagnostic usefulness.

Introduction: Early and accurate diagnosis of neurocognitive disorders including neurodegenerative dementia remains challenging. This study explores the impact of biological factors on serum neurofilament light chain (NfL) levels and clinical usefulness for the detection of neurocognitive disorders in a mixed memory clinic.

Methods: Serum samples and clinical data were obtained from 1188 patients who underwent diagnostic investigations for memory complaints between January 2018 and September 2019.

Subclinical Epileptiform Activity in Dementia with Lewy Bodies.

Background: Patients with dementia with Lewy bodies (DLB) have a higher probability of seizures than in normal aging and in other types of neurodegenerative disorders. Depositions of α-synuclein, a pathological hallmark of DLB, can induce network excitability, which can escalate into seizure activity. Indicator of seizures are epileptiform discharges as observed using electroencephalography (EEG).

Progression of Blood-Brain Barrier Leakage in Patients with Alzheimer's Disease as Measured with the Cerebrospinal Fluid/Plasma Albumin Ratio Over Time.

Background: Studies have found a disruption of the blood-brain barrier (BBB) in patients with Alzheimer's disease (AD), but there is little evidence of the changes in the BBB over time. The cerebrospinal fluid's (CSF) protein concentration can be used as an indirect measurement for the permeability of the BBB using the CSF/plasma albumin quotient (Q-Alb) or total CSF protein.

Objective: In the current study, we wanted to investigate the changes in Q-Alb in patients with AD over time.

Detection of subclinical epileptiform discharges in Alzheimer's disease using long-term outpatient EEG monitoring.

Background: In patients with Alzheimer's disease (AD) without clinical seizures, up to half have epileptiform discharges on long-term in-patient electroencephalography (EEG) recordings. Long-term in-patient monitoring is obtrusive, and expensive as compared to outpatient monitoring. No studies have so far investigated if long-term outpatient EEG monitoring is able to identify epileptiform discharges in AD.

Levetiracetam Increases Hippocampal Blood Flow in Alzheimer's Disease as Measured by Arterial Spin Labelling MRI.

Background: Patients with Alzheimer's disease (AD) have an increased risk of developing epileptiform discharges, which is associated with a more rapid rate of progression. This suggests that suppression of epileptiform activity could have clinical benefit in patients with AD.

Objective: In the current study, we tested whether acute, intravenous administration of levetiracetam led to changes in brain perfusion as measured with arterial spin labeling MRI (ASL-MRI) in AD.

Endo-lysosomal protein concentrations in CSF from patients with frontotemporal dementia caused by mutation.

Introduction: Increasing evidence implicates proteostatic dysfunction as an early event in the development of frontotemporal dementia (FTD). This study aimed to explore potential cerebrospinal fluid (CSF) biomarkers associated with the proteolytic systems in genetic FTD caused by mutation.

Methods: Combining solid-phase extraction and parallel reaction monitoring mass spectrometry, a panel of 47 peptides derived from 20 proteins was analyzed in CSF from 31 members of the Danish -FTD family.

Systematic Review of EEG Coherence in Alzheimer's Disease.

Background: Magnitude-squared coherence (MSCOH) is an electroencephalography (EEG) measure of functional connectivity. MSCOH has been widely applied to investigate pathological changes in patients with Alzheimer's disease (AD). However, significant heterogeneity exists between the studies using MSOCH.

Cerebrospinal fluid glucose is not altered in patients with dementia.

Background: Studies have shown that the pathological changes of many dementia disorders begin several years before clinical onset. A connection between some of these pathophysiological changes and brain hypometabolism, seen in dementia disorders, is well established. Glucose is transported from the blood into the interstitial space, and the decreased demand for glucose by the degenerating brain tissue may thereby mirror increased levels of cerebrospinal fluid (CSF) glucose.

Long-Term EEG Monitoring in Patients with Alzheimer's Disease Using Ear-EEG: A Feasibility Study.

Background: Previous studies have reported that epileptiform activity may be detectible in nearly half of patients with Alzheimer's disease (AD) on long-term electroencephalographic (EEG) recordings. However, such recordings can be uncomfortable, expensive, and difficult. Ear-EEG has shown promising results for long-term EEG monitoring, but it has not been used in patients with AD.

Sixteen Weeks of Aerobic Exercise does not Alter Resting-state Connectivity of the Precuneus in Patients with Alzheimer's Disease.

Introduction: In healthy elderly persons and patients with mild cognitive impairment, physical exercise can increase functional brain connectivity in the default mode network (DMN) measured by restingstate functional magnetic resonance imaging (rs-fMRI). However, no studies have so far investigated the effect of physical exercise on functional resting-state connectivity in the DMN in patients with Alzheimer's disease (AD).

Objective: In a single-blinded randomized controlled trial, we assessed the effects of an aerobic exercise intervention of 16 weeks of physical exercise on DMN connectivity using rs-fMRI in patients with AD.

Pharmacological Medical Treatment of Epilepsy in Patients with Dementia: A Systematic Review.

Background: Patients with dementia have an increased risk of developing epilepsy, especially in patients with vascular dementia and Alzheimer's disease. In selecting the optimal anti- epileptic drug (AED), the possible side effects such as drowsiness and worsening of cognitive function should be taken into consideration, together with co-morbidities and type of epilepsy.

Objective: The current systematic review investigates the efficacy, tolerability, and changes in cognitive function after administration of AED in patients with dementia and epilepsy.

Cortical Frontoparietal Network Dysfunction in -Frontotemporal Dementia.

A rare cause of inherited frontotemporal dementia (FTD) is a mutation in the gene on chromosome 3 leading to the autosomal dominantly inherited FTD (-FTD). Since -FTD is clinically well-characterized, and patients show a distinct pattern of executive dysfunction, the condition offers possible insight in the early electroencephalographic (EEG) changes in the cortical networks. Specifically, EEG microstate analysis parses the EEG signals into topographies believed to represent discrete network activations.

Upwards Drift of Cerebrospinal Fluid Amyloid-β 42 Over Twelve Years in a Consecutive Clinical Cohort.

Amyloid-β 1-42 (Aβ1-42) measured in the cerebrospinal fluid (CSF) can be used as a diagnostic biomarker for Alzheimer's disease (AD) but an upward drift when using the INNOTEST ELISA has been suggested. We investigated the upwards drift of Aβ1-42 levels over a period of twelve years in a consecutive memory clinic cohort. We found a significant increase in Aβ1-42 from 2008 to 2019 independent of changes in tau.

Serum Neurofilament Light in Patients with Frontotemporal Dementia Caused by CHMP2B Mutation.

Introduction: The potential of neurofilament light (NfL) as a blood-based biomarker is currently being investigated in autosomal dominant neurodegenerative disease. This study explores the clinical utility of serum-NfL in frontotemporal dementia due to CHMP2B mutation (FTD-3).

Methods: This cross-sectional study included serum and CSF data from 38 members of the Danish FTD-3 family: 12 affected CHMP2B mutation carriers, 10 presymptomatic carriers, and 16 noncarriers.

Electroencephalographic Cross-Frequency Coupling as a Sign of Disease Progression in Patients With Mild Cognitive Impairment: A Pilot Study.

Mild cognitive impairment (MCI) refers to mild objective cognitive deficits and is associated with the later development of Alzheimer's disease (AD). However, not all patients with MCI convert to AD. EEG spectral power has shown promise as a marker of progression, but brain oscillations in different frequencies are not isolated entities.

Changes in the left temporal microstate are a sign of cognitive decline in patients with Alzheimer's disease.

Introduction: Large-scale brain networks are disrupted in the early stages of Alzheimer's disease (AD). Electroencephalography microstate analysis, a promising method for studying brain networks, parses EEG signals into topographies representing discrete, sequential network activations. Prior studies indicate that patients with AD show a pattern of global microstate disorganization.

Cerebrospinal Fluid/Plasma Albumin Ratio as a Biomarker for Blood-Brain Barrier Impairment Across Neurodegenerative Dementias.

Background: Previous studies have shown an association between disruption of the blood-brain-barrier (BBB) and dementias of different etiologies. The protein concentration of cerebrospinal fluid (CSF) can be used as an indirect measurement for the permeability of the BBB using the CSF/plasma albumin quotient (Q-Alb) or total CSF protein.

Objective: In the current study, we wanted to investigate Q-Alb and CSF protein concentration in dementias of different etiologies and the possible confounding factors.

Microstate Changes Associated With Alzheimer's Disease in Persons With Down Syndrome.

Down syndrome (DS) is associated with development of dementia due to Alzheimer's disease (AD). However, due to considerable heterogeneity in intellectual function among persons with DS, it is difficult to assess whether a person with DS has developed dementia due to AD (DS-AD). EEG spectral power has previously shown very promising results with increased slowing in DS-AD compared to DS.

Oscillatory connectivity as a diagnostic marker of dementia due to Alzheimer's disease.

Objective: Quantitative EEG power has not been as effective in discriminating between healthy aging and Alzheimer's disease as conventional biomarkers. But EEG coherence has shown promising results in small samples. The overall aim was to evaluate if EEG connectivity markers can discriminate between Alzheimer's disease, mild cognitive impairment, and healthy aging and to explore the early underlying changes in coherence.

Microstates as Disease and Progression Markers in Patients With Mild Cognitive Impairment.

Network dysfunction is well established in patients with Alzheimer's disease (AD) and has been shown to be present early in the disease. This is especially interesting in patients with mild cognitive impairment (MCI) since they are more likely to develop AD. In EEG, one type of network analysis is microstates where the EEG is divided into quasi-stable states and these microstates have been linked to networks found with resting state functional MRI.

Gamma tACS over the temporal lobe increases the occurrence of Eureka! moments.

The solution to a problem might manifest itself as a burst of unexpected, unpredictable clarity. Such Eureka! events, or Insight moments, are among the most fascinating mysteries of human cognition, whose neurophysiological substrate seems to include a role for oscillatory activity within the α and γ bands in the right parietal and temporal brain regions. We tested this hypothesis on thirty-one healthy participants using transcranial Alternating Current Stimulation (tACS) to externally amplify α (10 Hz) and γ (40 Hz) activity in the right parietal and temporal lobes, respectively.

Altered Low-Frequency EEG Connectivity in Mild Cognitive Impairment as a Sign of Clinical Progression.

Background: Mild cognitive impairment (MCI) is associated with clinical progression to Alzheimer's disease (AD) but not all patients with MCI convert to AD. However, it is important to have methods that can differentiate between patients with MCI who progress (pMCI) and those who remain stable (sMCI), i.e.

Decreased Parietal Beta Power as a Sign of Disease Progression in Patients with Mild Cognitive Impairment.

Background: Electroencephalography (EEG) power has previously been used to compare mild cognitive impairment (MCI) patients who progress to Alzheimer's disease (pMCI) with patients with MCI who remain stable (sMCI) by using beta power. However, the beta band is very broad and smaller frequency bands may improve accuracy.

Objective: In the present study, we wanted to investigate whether it was possible to find any differences between pMCI and sMCI using relative power and whether these differences were correlated to cognitive function or neuropathology markers.