Whole brain segmentation: automated labeling of neuroanatomical structures in the human brain.

http://download.neurosky.com/docs/papers/bcq/Klimesch_1999_EEG_alpha_and_theta_oscillations_reflect_cognitive_and_memory_performance.pdf

EEG alpha and theta oscillations reflect cognitive and memory performance: a review and analysis

Nonlinear dynamical analysis of EEG and MEG: Review of an emerging field

http://raphe.kaist.ac.kr/publication/2004-EEG%20dynamics%20in%20patients%20with%20Alzheimer’s%20disease.pdf

EEG dynamics in patients with Alzheimer's disease

pare directly results based on cross-sectional and longitudinal data. Methods: Thirty-nine healthy control subjects (age range, 31-84 years) underwent serial magnetic resonance imaging assessments. Measurements included the whole-brain, temporal lobe, hippocampal, and ventricular volumes at baseline and for repeat scans. Results: We found significant decreases in crosssectionalwhole-brain(P.001),temporallobe(P.001), andhippocampal(P=.003)volumesandasignificantincrease in ventricular volume (P.001) with increasing age. Cross-sectional and longitudinal estimates of atrophy rates were similar. We also found directional evidenceofaccelerationinatrophyrateswithincreasingage in all analyses, with the most marked changes occurring after 70 years of age. This increase in rates after 70 years ofagewasparticularlymarkedintheventricles(P.001) and the hippocampi (P=.01). Conclusions:We found a significant age-associated decrease in global and regional brain volumes. Some evidence indicates that this decline in brain volumes may beduetoanonlinearaccelerationinratesofatrophywith increasingage.Abetterunderstandingofthisprocessmay helptodiscriminatenormalage-relatedchangesfromneurodegenerative diseases. Arch Neurol. 2003;60:989-994

https://jamanetwork.com/journals/jamaneurology/articlepdf/784396/noc20190.pdf

A longitudinal study of brain volume changes in normal aging using serial registered magnetic resonance imaging.

Discrimination of Alzheimer's disease and normal aging by EEG data

Parameters of EEG dimensional complexity in Alzheimer's disease

BACKGROUND We examined the differences in volume of the ventricular and extracerebral cerebrospinal fluid spaces in normal ageing and in probable Alzheimer's disease (AD) and we tried to investigate the effects of the severity of illness on the morphometric differentiation of AD and ageing, the principal components underlying brain atrophy in both conditions, and the correlations of these measurements with clinical findings.

METHOD Forty patients with probable AD were matched with 40 non-demented elderly controls. Both groups underwent standardised clinical tests and unenhanced cranial computed tomography for post hoc volumetric analysis.

RESULTS The lateral and third ventricles and the anterior and lateral fissures were significantly larger in AD than in normal ageing. The volumes of the lateral ventricle and lateral fissure permitted a highly efficient differentiation between normal ageing and AD even at the mild stage of dementia, and this differentiation was improved further in the more severe stages of illness. We identified one principal component underlying brain atrophy in normal ageing and two components in AD: a 'grey matter' component accounting for sulcal and third ventricular enlargement, and a 'white matter' component for lateral ventricular enlargement. In AD, most of the volumetric measurements were significantly correlated with cognitive impairment, but in the group of non-demented elderly controls they were correlated with age. CONCLUSION. Volumetric indices of brain atrophy permit a highly efficient differentiation between normal ageing and AD even in the mild stages of illness and this demonstrates that substantial structural brain changes have developed in the preclinical phase of illness. We suggest that there is an uncoupling between lateral ventricular enlargement and cortical brain atrophy in AD.

Brain atrophy in normal ageing and Alzheimer's disease. Volumetric discrimination and clinical correlations.

BACKGROUND The natural course of cognitive performance, electrophysiological alterations and brain atrophy in ageing and Alzheimer's disease (AD) has been investigated in numerous studies, but only few attempts have been made to examine the relationship between clinical, electroencephalographic (EEG) and morphological changes with quantitative methods prospectively over longer periods of time.

METHOD Fifty-five patients with clinically diagnosed AD and 66 healthy elderly controls were examined biannually using a cognitive test (CAMCOG), EEG band power and volumetric estimates of brain atrophy.

RESULTS On average cognitive performance deteriorated by 28 points on the CAMCOG in the AD group, the alpha/theta ratio decreased by 0.2, and the proportion of intracranial cerebrospinal fluid volume increased by 3.5% during a 2-year period. Similar changes were observed after a second 2-year interval. A multiple regression model demonstrated a significant influence of age on cognition and atrophy and a significant influence of the estimated duration of symptoms on cognition, alpha/theta ratio and brain atrophy at the initial examination. Cognitive performance at the first examination exerted significant effects on the performance and also on brain atrophy at re-examination after 2 or 4 years, whereas the EEG and neuroimaging findings at the previous examination were exclusively related to the corresponding findings at the follow-up examinations. In the control group no significant cognitive, EEG and morphological changes were observed after 2 and 4 years.

CONCLUSION After 2 consecutive follow-up periods, we were able to verify significant deteriorations of cognition accompanied by neurophysiological and neuroradiological changes in AD, but not in normal ageing. In clinically diagnosed AD, cognitive performance at the followup examination could not be predicted by the previous alpha/theta ratio or by the previous degree of global brain atrophy, whereas the cognitive test score determined not only performance, but also structural findings at follow-up. Performance on cognitive tests appears to be a more sensitive indicator of the degenerative process than EEG band-power and morphological changes in manifest AD. Neuroimaging, neurophysiology and genetic risk markers may be more important for the early differential diagnosis than for the prediction of the course of illness.

R Zerfass

Papers

Discrimination of Alzheimer's disease and normal aging by EEG data

Parameters of EEG dimensional complexity in Alzheimer's disease

Brain atrophy in normal ageing and Alzheimer's disease. Volumetric discrimination and clinical correlations.

Longitudinal cognitive, electroencephalographic and morphological brain changes in ageing and Alzheimer's disease.

Grundzuge des diagnostischen Vorgehens bei Demenzverdacht