The relationship between the diagnosis method of neuronal dysfunction (DIMENSION) and brain pathology in the early stages of Alzheimer's disease

Abstract

Objectives: To examine whether the diagnosis method of neuronal dysfunction (DIMENSION), a new electroencephalogram (EEG) analysis method, reflected pathological changes in the early stages of Alzheimer's disease (AD), we conducted a comparative study of cerebrospinal fluid markers and single-photon emission computed tomography. Methods: Subjects cincluded 32 patients in the early stages of AD with a Mini-Mental State Examination score Ն24 (14 men, 18 women; mean age, 77.3 1 9.2 years). Cerebrospinal fluid samples were collected from AD patients, and cerebrospinal fluid levels of phosphorylated tau protein (p-tau) 181 and amyloid b (Ab) 42 were measured with sandwich ELISA. EEG recordings were performed for 5 min with the subjects awake in a resting state with their eyes closed. Then, the mean value of the EEG alpha dipolarity (Da) and the standard deviation of the EEG alpha dipolarity (Ds) were calculated with DIMENSION. Single-photon emission computed tomography analyses were also performed for comparison with DIMENSION measures. Results: Patients with parietal hypoperfusion had significantly increasing p-tau181, decreasing Da, and increasing Ds. In addition, there was a negative correlation between Da and p-tau181, p-tau181/Ab42, and a positive correlation between Ds and p-tau181/Ab42. Conclusion: Da and Ds were related to cerebral hypoperfusion and p-tau181/Ab42. DIMENSION was able to detect changes in the early-stage Alzheimer's brain, suggesting that it is possibility as a useful examination for early-stage AD with a difficult discrimination in clinical conditions. Moreover, EEG measurement is a quick and easy diagnostic test and is useful for repeated examinations.

Changes of Functional and Directed Resting-State Connectivity Are Associated with Neuronal Oscillations, ApoE Genotype and Amyloid Deposition in Mild Cognitive Impairment

“…In a computational model, it was recently found that Aβ can induce (hippocampal) theta band power changes (Zou et al, 2011 ). A recent study examined in patients with early stages of AD the link between Aβ42 (based on measures from the cerebrospinal fluid), phosphorylated tau protein (p-tau), and (resting-state) EEG alpha dipolarity and its standard deviation (Kouzuki et al, 2013 ). The authors found a negative correlation between alpha dipolarity and p-tau as well as between alpha dipolarity and Aβ42/p-tau.…”

EEG and Neuronal Activity Topography analysis can predict effectiveness of shunt operation in idiopathic normal pressure hydrocephalus patients

“…This is related to the fact that EEG directly relates to cortical electrical activity with a high temporal resolution and that NPV is particularly sensitive to the transition of cortical electrical activity. Although there are some other recently developed EEG methods which are connectivity ( Fonseca et al, 2013 ), complexity ( Mizuno et al, 2010 ) microstate ( Nishida et al, 2013 ) and dimension analysis ( Kouzuki et al, 2013 ), NAT analysis can more sensitively detect instability of cortical electrical activity prior to phase transition onset because theoretical model showed that NPV diverges to infinity as state approaches a phase transition point ( Chen et al, 2012 ). Therefore, we selected NAT analysis to detect cortical activity changes in iNPH patients.…”

Electroencephalogram and Alzheimer’s Disease: Clinical and Research Approaches

“…A newly introduced EEG analysis named method of neuronal dysfunction (DIMENSION) found a negative correlation between the mean value of EEG alpha dipolarity and p-Tau 181 as well as the ratio p-Tau 81/A β 42 and a positive correlation between the standard deviation of EEG alpha dipolarity [62]. …”

“…According to their results AD patients with parietal hypoperfusion had decreasing mean value of EEG alpha dipolarity and increasing standard deviation of EEG alpha dipolarity [62]. …”