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Alzheimer's disease dementia (ADD) is the most diffuse neurodegenerative disorder belonging to mild cognitive impairment (MCI) and dementia in old persons. This disease is provoked by an abnormal accumulation of amyloid-beta and tauopathy proteins in the brain. Very recently, the first disease-modifying drug has been licensed with reserve (i.e., Aducanumab). Therefore, there is a need to identify and use biomarkers probing the neurophysiological underpinnings of human cognitive functions to test the clinical efficacy of that drug. In this regard, event-related electroencephalographic potentials (ERPs) and oscillations (EROs) are promising candidates. Here, an Expert Panel from the Electrophysiology Professional Interest Area of the Alzheimer's Association and Global Brain Consortium reviewed the field literature on the effects of the most used symptomatic drug against ADD (i.e., Acetylcholinesterase inhibitors) on ERPs and EROs in ADD patients with MCI and dementia at the group level. The most convincing results were found in ADD patients. In those patients, Acetylcholinesterase inhibitors partially normalized ERP P300 peak latency and amplitude in oddball paradigms using visual stimuli. In these same paradigms, those drugs partially normalize ERO phase-locking at the theta band (4–7 Hz) and spectral coherence between electrode pairs at the gamma (around 40 Hz) band. These results are of great interest and may motivate multicentric, double-blind, randomized, and placebo-controlled clinical trials in MCI and ADD patients for final cross-validation. United States Department of Health & Human Services National Institutes of Health (NIH) - USA

There is clear evidence that normal aging and dementia caninfluence the ability to recognize facial emotions. Different dementiapatients could have different types of disabilities in their emotionalfunctions. The study aimed tofind out how the event-relatedoscillatory response changes with aging and dementia during theemotional paradigm. 25 patients with amnestic-Mild CognitiveImpairment (aMCI), 25 Alzheimer’s Disease patients (AD), 16Parkinson’s Disease patients with mild cognitive impairment(PDMCI), 16 Parkinson’s Disease patients with dementia (PDD) andage, education, gender matched 25 healthy elderly (HE) wereincluded in the study. Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)

In recent years, quantitative variables derived from the electroencephalogram (EEG) attract an increasing interest for the evaluation of neurodegenerative diseases, as EEG registers the neuro-electric activity with a high temporal resolution and provides a cost-effective and easily accessible, non-invasive method. Event-related oscillations (EROs) as oscillatory responses in the EEG to specific events further provide the possibility to track the cognitive decline in a task-specific manner. Current study in search for potential ERO biomarkers to distinguish different stages of cognitive decline along the Alzheimer's Disease (AD) continuum re-analyzed a combined set of data collected and analyzed in previous studies by Basar and coworkers. Target responses of a visual oddball experiment recorded from 33 AD patients, 46 Mild Cognitive Impairment (MCI) patients and 48 age, gender, and education matched normal elderly controls were analyzed for both evoked (phase-locked) and total (phase-locked + non-phase-locked) ERO powers in delta, theta, alpha, beta and gamma bands by applying continuous wavelet transform (WT) on averaged and single trial data, respectively. The cluster-based non-parametric permutation test implemented in the FieldTrip toolbox revealed significant differences among the three groups. While the total delta and theta responses already significantly declined in the MCI stage with further spatial expansion of the decline in AD, the evoked delta response reached a statistically significant reduction level in the AD stage. We obtained no significant difference among groups for alpha, beta and gamma frequency bands. These results suggest that total delta and theta EROs to oddball targets may be useful for early detection of the disease in MCI stage, while the evoked delta response allows detecting the conversion to AD. Istanbul University

Alzheimer's disease (AD) is the most common neurodegenerative disease among the elderly with a progressive decline in cognitive function significantly affecting quality of life. Both the prevalence and emotional and financial burdens of AD on patients, their families, and society are predicted to grow significantly in the near future, due to a prolongation of the lifespan. Several lines of evidence suggest that modifications of risk-enhancing life styles and initiation of pharmacological and non-pharmacological treatments in the early stage of disease, although not able to modify its course, helps to maintain personal autonomy in daily activities and significantly reduces the total costs of disease management. Moreover, many clinical trials with potentially disease-modifying drugs are devoted to prodromal stages of AD. Thus, the identification of markers of conversion from prodromal form to clinically AD may be crucial for developing strategies of early interventions. The current available markers, including volumetric magnetic resonance imaging (MRI), positron emission tomography (PET), and cerebral spinal fluid (CSF) analysis are expensive, poorly available in community health facilities, and relatively invasive. Taking into account its low cost, widespread availability and non-invasiveness, electroencephalography (EEG) would represent a candidate for tracking the prodromal phases of cognitive decline in routine clinical settings eventually in combination with other markers. In this scenario, the present paper provides an overview of epidemiology, genetic risk factors, neuropsychological, fluid and neuroimaging biomarkers in AD and describes the potential role of EEG in AD investigation, trying in particular to point out whether advanced analysis of EEG rhythms exploring brain function has sufficient specificity/sensitivity/accuracy for the early diagnosis of AD.

Extending Basar's theory of event-related EEG oscillations, here we hypothesize that even in quiet wakefulness, transient increases in delta rhythms may enhance global cortical arousal as revealed by the desynchronization of alpha rhythms in normal (Nold) seniors with some derangement in Alzheimer's disease dementia (ADD).Clinical and EEG datasets in 100 ADD and 100 Nold individuals matched as demography, education, and gender were taken from an international archive. Standard delta (< 4 Hz) and alpha1 (8-10.5 Hz) bands were used for the main analysis, while alpha2 (10.5-13 Hz), theta (4-8 Hz), beta1 (13-20 Hz), beta2 (20-35 Hz), and gamma (35-40 Hz) served as controls. In the interpretation, the higher the alpha1 power (density), the lower that arousal. As expected, when compared to the Nold group, the ADD group showed higher global (scalp) power density at the delta-theta band and lower global power density at the alpha-beta bands. As novel findings, we observed that: (1) in the Nold group, the global delta and alpha1-2 power were negatively and linearly correlated; (2) in the ADD group, this correlation was just marginal; and (3) in both Nold and AD groups, the EEG epochs with the highest delta power (median value for stratification) were associated with the lowest global alpha1 power. This effect was related to eLORETA freeware solutions showing maximum alpha1 source activations in posterior cortical regions.These results suggest that even in quiet wakefulness, delta and alpha rhythms are related to each other, and ADD partially affects this cross-band neurophysiological mechanism. Ministry of Health, Italy ; Ministry of Health Italy - Ricerca Corrente (MOH-RC) ; H2020 Marie S. Curie ITN-ETN project with the short title "BBDiag" ; H2020-TWINN-2015 project with the short title "SynaNet"

Objective: Here we tested if cortical sources of resting state electroencephalographic (rsEEG) rhythms may differ in sub-groups of patients with prodromal and overt dementia with Lewy bodies (DLB) as a function of relevant clinical symptoms.Methods: We extracted clinical, demographic and rsEEG datasets in matched DLB patients (N = 60) and control Alzheimer's disease (AD, N = 60) and healthy elderly (Nold, N = 60) seniors from our international database. The eLORETA freeware was used to estimate cortical rsEEG sources.Results: As compared to the Nold group, the DLB and AD groups generally exhibited greater spatially distributed delta source activities (DLB > AD) and lower alpha source activities posteriorly (AD > DLB). As compared to the DLB ``controls", the DLB patients with (1) rapid eye movement (REM) sleep behavior disorders showed lower central alpha source activities (p < 0.005); (2) greater cognitive deficits exhibited higher parietal and central theta source activities as well as higher central, parietal, and occipital alpha source activities (p < 0.01); (3) visual hallucinations pointed to greater parietal delta source activities (p < 0.005).Conclusions: Relevant clinical features were associated with abnormalities in spatial and frequency features of rsEEG source activities in DLB patients.Significance: Those features may be used as neurophysiological surrogate endpoints of clinical symptoms in DLB patients in future cross-validation prospective studies. Ministry of Health, Italy; H2020 Marie S. Curie ITN-ETN project; H2020-TWINN-2015 project

The research on the abnormalities of event-related oscillations in Parkinson's disease (PD) was mostly studied with cognitively normal patients. The present study aims to show the adverse effects of cognitive decline in PD patients via the EEG-Brain Oscillations approach by comparing the electrophysiological responses in two modalities, i.e. auditory, and visual in which PD group show deficit. We conducted a study in which we analyzed event-related theta power and phase-locking during auditory and visual oddball paradigm. Cognitively normal PD (PDCN) patients (N = 15), PD with mild cognitive impairment (PDMCI) patients (N = 22), PD dementia (PDD) patients (N = 11) and healthy controls (HC) (N = 17) were included in the study. Neuropsychological assessments were applied to all participants. There was a gradual decrease in scores of neuropsychological tests (HC, PDCN, PDMCI, PDD, respectively). Most of the neuropsychological test scores of the participants were highly correlated with the theta power and theta phase locking values, especially over frontal-central areas. HC had higher theta phase-locking and power in comparison to PDMCI and PDD. The differentiation between HC and PDCN was specific to frontal-central areas. Theta power and theta phase-locking were decreased overall locations in PDMCI and PDD both during visual and auditory oddball paradigms compared with PDCN. The results indicate that theta responses in PD patients decreased gradually as the cognitive decline increased. We can conclude that complex abnormalities in their neurotransmitter and neuronal signal systems that occur with the progression of the disease could be responsible for these results.

Studies on Event Related EEG Brain Oscillations presentedessential results on understanding cognitive brain function andcognitive decline in different pathologies. The present study aims toanalyze the abnormalities of cognitive and emotional processes in PDpatients with and without dementia compared to healthy controls Intwo different setups, EEG of PD patients without cognitive deficits,PD patients with Mild Cognitive Impairment, PD Dementia, andhealthy controls were recorded during visual, auditory oddballparadigms and facial expression paradigm. Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)

Characterizing brain activity at rest is of paramount importance to our understanding both of general principles of brain functioning and of the way brain dynamics is affected in the presence of neurological or psychiatric pathologies. We measured the time-reversal symmetry of spontaneous electroencephalographic brain activity recorded from three groups of patients and their respective control group under two experimental conditions (eyes open and closed). We evaluated differences in time irreversibility in terms of possible underlying physical generating mechanisms. The results showed that resting brain activity is generically time-irreversible at sufficiently long time scales, and that brain pathology is generally associated with a reduction in time-asymmetry, albeit with pathology-specific patterns. The significance of these results and their possible dynamical etiology are discussed. Some implications of the differential modulation of time asymmetry by pathology and experimental condition are examined.

Facial Expression (FE) recognition is a major marker of emotional ability. Behavioral studies show that FE recognition ability decreases with aging. Studying how event-related brain oscillations change with normal aging is important to better understand the underlying mechanisms of emotional processes. The aim of this study is to investigate changes in FE recognition due to normal aging using the EEG-Brain Oscillations approach. Fifteen young and fifteen elderly healthy subjects were included in the study. 15 photographs were used with 5 different FEs (angry, happy, neutral, sad, fearful). After each EEG recording session, subjects were asked to identify the FEs that were presented. Event-related delta, theta and, alpha phase-locking and frequency-band responses were analyzed. In the FE recognition part of the study, young subjects obtained better scores than the elderly subjects. There was a significant result regarding the locationXgroup comparison in the delta response; the young group had a higher delta response than the elderly group over the occipital area. There were significant locationXgroup differences in the theta and alpha phase locking values; the elderly group had higher theta and alpha phase locking values than the young group in the frontal area. Group differences were significant in the theta response and theta phase locking; the elderly individuals' theta response and phase locking values were higher compared to those of the young individuals. In elderly individuals, FE recognition impairment has been observed. It has been shown that the impairment may be characterized by decreased occipital delta responses and phase locking. This can be interpreted to mean that elderly individuals may have developed different brain dynamics as a compensating mechanism since they are not as efficient as young individuals in performing these functions.

Guntekin, Bahar/0000-0002-0860-0524 WOS: 000498325100052 PubMed: 31477464 We have evaluated an 82 years old PD patient who has acutely developed VH secondary to acute visual loss that was associated with increased electroencephalographic activity in the gamma range over the parietal, occipital and frontal regions. In this respect, we have tested the therapeutic effect of occipital lobe oriented rTMS application and its electrophysiological correlates that led to significant improvement in the hallucinatory symptomatology of the patient after two weeks. We have revealed that the improved hallucinatory symptoms after rTMS application resolved completely after switching from the pramipexole treatment to L-Dopa indicating that there could be a combined therapeutic effect of L-Dopa and rTMS. Furthermore, Quantitative-Electroencephalography analysis has shown that the therapeutic effects of rTMS and L-Dopa were seen with the improvement of impaired gamma power spectrum. Although the main limitation of this report is that this a single case study and that these findings need to be replicated in a larger sample, e.g., as part of a controlled trial, our present findings help us to enlighten the unknown pathophysiological overlapping between the visual hallucinations in PD and Charles Bonnet Syndrome. Finally, our study revealed increased gamma coherence and power spectrum which is seen with visual hallucinations and improved after the application of 1 Hz rTMS on the occipital lobe. These findings together suggest that rTMS could be used as a therapeutic tool for parkinsonian complex VH and probably due affecting gamma coherence and power spectrum. (C) 2019 Elsevier Ltd. All rights reserved.

Orjinal Makale: Functional cortical source connectivity of resting state electroencephalographic alpha rhythms shows similar abnormalities in patients with mild cognitive impairment due to Alzheimer's and Parkinson's diseases. 129(4), 766-782. https://doi.org/10.1016/j.clinph.2018.01.009

Objectives: The present study aims to evaluate the amplitude and latency of event-related potentials (ERPs) P100, N170, VPP and N230 in individuals with Alzheimer's disease (AD) compared to healthy elderly controls, using a passive viewing task of emotional facial expressions. Methods: Twenty-four individuals with mild to moderate AD and 23 demographically matched healthy elderly controls were included in the study. ERP P100, N170, VPP and N230 amplitude and latency values were compared between groups. Results: The categorization of emotional facial expressions was intact; yet, increased P100 amplitude and latency, decreased N170 amplitude, and increased VPP amplitude were observed in AD compared to controls. Increased N230 amplitude and latency were observed in response to angry expressions, while neutral expressions elicited decreased amplitude and latency. Conclusions: Increased P100 amplitude and latency may reflect reduced amygdala volume and disruptions in the visual system, while decreased N170 and increased VPP amplitudes may reflect impaired perceptual processing, mitigated by a greater involvement of prefrontal areas for task performance in AD. Significance: This study is the first to report a complex pattern of ERPs to emotional facial expressions in individuals with AD. (C) 2019 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Amnesic mild cognitive impairment (MCI) represents a risk of developing Alzheimer's disease (AD), but not all MCI subjects progress to dementia of AD type. Magnetic resonance imaging (MRI) of cortical and hippocampal atrophy supports early diagnosis of AD in MCI subjects, while frontal event-related oscillations (EROS) at delta frequencies (

WOS: 000466619600006 PubMed ID: 30851280 Event-related oscillatory responses reflect the cognitive status in many neuropsychiatric conditions including mild cognitive impairment (MCI). In this study, a total of 30 patients with amnestic MCI (aMCI) and 25 patients with MCI of Parkinson's disease (PD-MCI) were compared with 28 aged-, gender-, education-matched healthy control (HC) participants using visual event-related delta, theta, alpha oscillatory responses by methods of event related spectral perturbation and inter-trial coherence. PD-MCI and aMCI groups commonly share a decreased theta power, but all electrophysiological deviations from the controls were more prominent in PD-MCI than aMCI in all frequency bands. Additionally, decreased phase-locking in all studied frequency bands was encountered only in PD-MCI group, but it was preserved in aMCI. These findings indicate that visual networks in PD-MCI are more severely affected than aMCI. Reduced phase-locking in PD-MCI may possibly relate to dysfunctioning subcortical modulating centers that take a role in the generation of event-related responses. Scientific and Technological Research Council of Turkey-TUBITAK [112S459] This study was supported by the Scientific and Technological Research Council of Turkey-TUBITAK (Project number: 112S459).

Hallucinations in Parkinson ‘s disease (PD) could affect about one-quarter of the patients. There are limited studies on how the hallucinations effect cognitive states of the patients with Parkinson’s disease.

WOS: 000427485900009 PubMed ID: 29448151 Objective: This study tested the hypothesis that markers of functional cortical source connectivity of resting state eyes-closed electroencephalographic (rsEEG) rhythms may be abnormal in subjects with mild cognitive impairment due to Alzheimer's (ADMCI) and Parkinson's (PDMCI) diseases compared to healthy elderly subjects (Nold). Methods: rsEEG data had been collected in ADMCI, PDMCI, and Nold subjects (N = 75 for any group). eLORETA freeware estimated functional lagged linear connectivity (LLC) from rsEEG cortical sources. Area under receiver operating characteristic (AUROC) curve indexed the accuracy in the classification of Nold and MCI individuals. Results: Posterior interhemispheric and widespread intrahemispheric alpha LLC solutions were abnormally lower in both MCI groups compared to the Nold group. At the individual level, AUROC curves of LLC solutions in posterior alpha sources exhibited moderate accuracies (0.70-0.72) in the discrimination of Nold vs. ADMCI-PDMCI individuals. No differences in the LLC solutions were found between the two MCI groups. Conclusions: These findings unveil similar abnormalities in functional cortical connectivity estimated in widespread alpha sources in ADMCI and PDMCI. This was true at both group and individual levels. Significance: The similar abnormality of alpha source connectivity in ADMCI and PDMCI subjects might reflect common cholinergic impairment. (C) 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved. H Marie S. Curie ITN-ETN project The present study was developed based on the data of the informal European Consortium PDWAVES and European Consortium of Dementia with Lewy Body. The members and institutional affiliations of the Consortia are reported in the cover page of this manuscript. Dr. Erol Basar passed away due to health problems on October 28th (November 18th 1938-October 28th 2017) in Istanbul, during the editorial processing of this manuscript. Until the end of his life, he had been working to the development of EEG science and its application in Clinical Neurophysiology. He leaves to all us an invaluable scientific legacy in the Science of Brain Rhythms and Human Cognition. He also leaves a permanent reminder of scientific passion, academic soul, and social responsibility to all fortunate people who met and knew him during his intense life. The research activities of the Unit of University of Rome "La Sapienza" were partially supported by the H2020 Marie S. Curie ITN-ETN project with the short title "BBDiag" (http://bbdiag-ITNetn.eu). We thank Mrs. Jessica Janson and Mrs. Marina Selivanova for their support to those activities in the framework of the BBDiag project.

Brain oscillations in the gamma frequency band, - i.e. oscillations greater than 25 Hz - have attracted increasing attention over the last few decades in the research of sensory-cognitive processes. In the neuroscience research literature, a great number of reports aim to describe the functional correlates of oscillatory responses in the gamma frequency window. However, analysis using a broadband frequency window often leads to divergent functional interpretations and controversies. In order to provide a more exact approach, we have used a strategy by defining multiple frequency and multiple time windows according to the combined analysis of conventional power spectral windows, frequency adaptive multiple filters, and inter-trial coherence. The analysis in frequency windows of 25-30 Hz, 30-35 Hz, and 4048 Hz enables the investigator to provide a distinction of cognitive and/or sensory responses. Moreover, according to topological differentiation and the consideration of neuroanatomic pathways, more reliable interpretations of gamma responses are reached. (C) 2015 The Authors. Published by Elsevier B.V.

Kurt, Pınar (Arel Author), Eroğlu, Kübra (Arel Author), Kuzgun Bayram, Tubanur (Arel Author), The modulation of delta oscillations (0.5-3.5 Hz) by emotional stimuli is reported. Physical attributes such as color, brightness and spatial frequency of emotional visual stimuli have crucial effect on the perception of complex scene. Brightness is intimately related with emotional valence. Here we explored the effect of brightness on delta oscillatory responses upon presentation of pleasant, unpleasant and neutral pictures. We found that bright unpleasant pictures elicited lower amplitude of delta response than original unpleasant pictures. The electro-physiological finding of the study was in accordance with behavioral data. These results denoted the importance of delta responses on the examination of the association between perceptual and conceptual processes while in the question of brightness and emotion.

Introduction: Cognitive Impairment in Parkinson’s disease could occur by the progression of the disease. Event-related theta responses in the frontal region is strongly connected with cognitive processes. Increase of theta response during increased cognitive load is a robust finding. The decrease theta phase-locking and theta power was found in the patient groups which had cognitive decline. The aim of the present study is to investigate the event-related theta responses in Parkinson Patients with and without cognitive deficits during auditory and visual cognitive paradigms. Methods: Three different group of Parkinson’s disease patients were included in the study. 15 PD patients without cognitive deficits, 23 PD patients with mild cognitive impairment (MCI), 11 PD patients with dementia, and 18 aged-matched healthy controls (HC) were included in the study. The mean of Mini Mental State Examination (MMSE) scores was 28,00±1,25 for the HC group, 26,80±1,90 for the PD group, 22,56±5,32 for the PD-MCI group, and 18,82±3,74 for the PD-Dementia group. EEG was recorded at 8 different frontal locations (F3-F4, F7-F8, FC3-FC4, and FT7-FT8). Auditory and visual oddball paradigms were applied during EEG recordings. Phase-locking analysis (Inter-trial coherence) and event related power spectrum were analyzed for theta (4-7 Hz) frequency band for all subject groups for both “target” and non-target” stimulations. Results: In accordance with the previous studies target stimulation elicited higher theta phase-locking and theta power than the non-target stimulation (p

Background Studies on Event Related EEG Brain Oscillations presented essential results on the understanding of cognitive brain function and cognitive decline in different pathologies. Event related oscillatory dynamics in Parkinson’s disease (PD) have not been studied comprehensively. In the last three years, our group aimed to fulfill this critical gap. Material and methods 27 PD patients without cognitive deficits, 34 PD patients with Mild Cognitive Impairment, 22 patients with PD Dementia and 33 healthy controls were included in the study.EEG was recorded during visual and auditory oddball paradigEvent related power spectrum, phase locking, event related coherence were evaluated in delta, theta, alpha, beta and gamma frequency bands for all group of subjects. Results Event related delta, theta, alpha and beta power and phase locking increased with a cognitive load in healthy subjects but these responses decreased in PD patients who have mild cognitive impairment and dementia. Event related delta, theta, and alpha coherence values were also lower in PD patients with cognitive deficits. The most differentiated results were found in the theta frequency band, frontal theta responses were the lowest in PD patients with dementia especially during the visual paradigm rather than the auditory paradigm. Conclusions Comprehensive analysis of Event-related oscillatory dynamics could successfully differentiate the cognitive decline in Parkinson’s disease patients. The differentiation between subject groups did not just appear in local circuits, but long distance connections were also impaired in PD patients with cognitive decline. Acknowledgments This work (Grant No. 214S111 ) was supported by TUBITAK .

Background Event-related beta responses are related to the visual cognitive process. Beta phase-locking had decreased in subjects with cognitive deficits. Parkinson’s disease dementia (PDD) and dementia with Lewy bodies (DLB) have similar pathophysiology and have different clinical symptoEEG event-related responses in neurodegenerative diseases are remarkable for understanding the mechanisms underlying the pathophysiology. The aim of our study was to investigate the event-related beta responses in PDD and DLB patients. Material and methods 12 DLB, 14 PDD patients and matched 15 healthy controls were included in the study. There was no significant difference for the Mini-Mental State Examination score between the patient groups. EEG recordings were performed from 32 different locations during visual oddball paradigm. Phase-locking analysis was performed for beta (15–25 Hz) frequency band for all subject groups. Repeated measures of ANOVA was used for statistical analysis (p Results Healthy controls had increased beta phase locking with increasing cognitive loading. Healthy controls had higher beta phase locking than both PDD and DLB patients. LocationXGroup effect was significant for beta phase locking (p = 0.002). DLB patients had the worst beta phase locking particularly in parietal and occipital locations in comparison to other groups. Conclusions The present study showed that dementia characterized by a cognitive decline is reflected with decreased beta phase locking in posterior areas in both Parkinson’s disease and Lewy body disease. The decreased event-related beta phase locking could be a candidate of biomarkers for dementia in PDD and DLB patients.

18th World Congress of Psychophysiology of the International Organization of Psychophysiology (IOP) -- AUG 31-SEP 04, 2016 -- Havana, CUBA WOS: 000382408700195 Background: In the last decade research on delta oscillatoryresponses invaded the literature. One of thefirst research on thisarea showed that delta responses increase upon cognitive load(Başar and Stampfer 1985). After this preliminary result, manyresearchers have shown that delta responses are related to attention,perception, decision making and working memory processes. Ourgroup and other groups in the literature indicated that the deltaresponses in different patient groups were decreased duringcognitive load in comparison to healthy controls. In a recent reviewwe have described that decrease of delta responses could be acandidate of a general electrophysiological biomarker for neuropsy-chiatric disorders (Güntekin and Başar 2015). Delta responses weredecreased in Alzheimer’s disease, in Mild Cognitive impairment(MCI) in bipolar disorder patients and as well as in schizophreniapatients during cognitive load in comparison to healthy controls. Inthe present study we analyze the delta responses in Parkinson’sdisease with and without cognitive deficits Int Org Psychophysiol

Background: The purpose of this study was to investigate changes in delta event-related oscillations (EROs) in younger and older healthy elderly subjects. We hypothesized that delta EROs were affected by age-related changes, which could be reflected in a visual oddball paradigm. Method: The study included two groups of subjects, 17 younger healthy elderly (mean age: 63.1 +/- 2.8 years) and 17 gender- and education-matched older healthy elderly (mean age: 79.6 +/- 5.2 years), who performed a visual oddball paradigm. EEG was recorded from F-3, F-z, F-4, C-3, C-z, C-4, P-3, P-z, P-4, O-1, O-z and O-2 locations. Peak-to-peak amplitudes of delta (0.5-3 Hz) target ERO responses during the post-stimulus 0-800 ms time window were measured. Repeated measures of ANOVA was used to analyze four locations (frontal, central, parietal, occipital), at three sagittal (left, midline, right) sites. Independent t-tests were applied for post-hoc analyses. Results: The older healthy elderly group had 16-25% lower values for the maximum peak-to-peak amplitudes of delta ERO compared with the younger healthy elderly group over frontal (p < 0.003), central (p < 0.0001) and parietal (p < 0.007) locations [F-3.95 = 4396, p = 0.015] Furthermore, there was a moderate negative correlation between age and C-z peak-to-peak amplitude of target delta responses [r = -0.401, p < 0.02], indicating the notion that peak-to-peak amplitude of C-z decreases as age increases. Conclusion: In the present study younger healthy elderly showed significantly higher event-related delta responses than older healthy elderly at frontal, central and parietal locations. Moreover, delta ERO responses decreased in accordance with age. (C) 2015 Elsevier B.V. All rights reserved.

There are few studies describing gender differences in event related oscillations (EROS). In the present report we demonstrate that gender differences are apparent in EROS even during simple visual stimulation, possibly activating very basic sensory networks. The data of 32 (16 males) healthy subjects were recorded from thirteen different scalp locations (F-3, F-4, C-z, C-3, C-4, T-3, T-4, T-5, T-6, P-3, P-4, O-1, O-2). Analysis was performed in the delta (0.5-3.5 Hz), theta (5-8.5 Hz), alpha (9-13 Hz), beta (15-24 Hz), and gamma (28-48 Hz) frequency ranges. The results showed that the maximum peak-to-peak delta response amplitudes for women were significantly higher than for men over occipital, parietal, central and temporal electrode locations. There were also differentiations in the beta and gamma oscillatory responses. These gender differences were most pronounced over the electrode Site O-2, that is, over primary visual areas. It is suggested that this study might serve as a standard to investigate gender differences in electrophysiology. (c) 2007 Elsevier B.V All rights reserved.

The Cartesian System is a fundamental conceptual and analytical framework related and interwoven with the concept and applications of Newtonian Dynamics. In order to analyze quantum processes physicist moved to a Probabilistic Cartesian System in which the causality principle became a probabilistic one. This means the trajectories of particles (obeying quantum rules) can be described only with the concept of cloudy wave packets. The approach to the brain-body-mind problem requires more than the prerequisite of modern physics and quantum dynamics. In the analysis of the brain-body-mind construct we have to include uncertain causalities and consequently multiple uncertain causalities. These multiple causalities originate from (1) nonlinear properties of the vegetative system (e.g. irregularities in biochemical transmitters, cardiac output, turbulences in the vascular system, respiratory apnea, nonlinear oscillatory interactions in peristalsis); (2) nonlinear behavior of the neuronal electricity (e.g. chaotic behavior measured by EEG), (3) genetic modulations, and (4) additional to these physiological entities nonlinear properties of physical processes in the body. The brain shows deterministic chaos with a correlation dimension of approx. D(2)=6, the smooth muscles approx. D(2)=3. According to these facts we propose a hyper-probabilistic approach or a hyper-probabilistic Cartesian System to describe and analyze the processes in the brain-body-mind system. If we add aspects as our sentiments, emotions and creativity to this construct, better said to this already hyper-probabilistic construct, this "New Cartesian System" is more than hyper-probabilistic, it is a nebulous system, we can predict the future only in a nebulous way; however, despite this chain of reasoning we can still provide predictions on brain-body-mind incorporations. We tentatively assume that the processes or mechanisms of the brain-body-mind system can be analyzed and predicted similar to the metaphor of "finding the walking path in a cloudy or foggy day". This is meant by stating "The Nebulous Cartesian System" (NCS). Descartes, at his time undertaking his genius step, did not possess the knowledge of today's physiology and modern physics; we think that the time has come to consider such a New Cartesian System. To deal with this, we propose the utilization of the Heisenberg S-Matrix and a modified version of the Feynman Diagrams which we call "Brain Feynman Diagrams". Another metaphor to consider within the oscillatory approach of the NCS is the "string theory". We also emphasize that fundamental steps should be undertaken in order to create the own dynamical framework of the brain-body-mind incorporation; suggestions or metaphors from physics and mathematics are useful; however, the grammar of the brains intrinsic language must be understood with the help of a new biologically founded, adaptive-probabilistic Cartesian system. This new Cartesian System will undergo mutations and transcend to the philosophy of Henri Bergson in parallel to the Evolution theory of Charles Darwin to open gateways for approaching the brain-body-mind problem.

This is a pilot study describing event-related oscillations in patients with Alzheimer-type dementia (AD). Theta responses of 22 mild probable AD subjects according to NINCDS-ADRDA criteria (11 non-treated, 11 treated by cholinesterase inhibitors), and 20 healthy elderly controls were analyzed by using the conventional visual oddball paradigm. We aimed to compare theta responses of the three groups in a range between 4-7 Hz at the frontal electrodes. At F-3 location, theta responses of healthy subjects were phase locked to stimulation and theta oscillatory responses of non-treated Alzheimer patients showed weaker phase-locking, i.e. average of Z-transformed means of correlation coefficients between single trials was closer to zero. In treated AD patients, phase-locking following target stimulation was two times higher in comparison to the responses of non-treated patients. The results indicate that the phase-locking of theta oscillations at F-3 in the treated patients is as strong as the control subjects. The F-4 theta responses were not statistically significant between the groups. Our findings imply that the theta responses at F3 location are highly unstable in comparison to F4 in non-treated mild AD patients and cholinergic agents may modulate event-related theta oscillatory activities in the frontal regions. (c) 2006 Elsevier B.V. All rights reserved.

18th World Congress of Psychophysiology of the International Organization of Psychophysiology (IOP) -- AUG 31-SEP 04, 2016 -- Havana, CUBA WOS: 000382408700070 … International Organization of Psychophysiology

Background CBD is a neurodegenerative disorder characterized by asymmetric motor parkinsonism symptomatology and impairment in language, personality and affective functions that are related to frontoparietal atrophy. To date, there is still no effective treatment for CBD. In this respect, TMS may be a novel therapeutic candidate for CBS. Considering all of this evidence, we aimed to evaluate the pre and post-treatment electrophysiological, neurometabolic and neuropsychometric correlates of TMS application in four CBS patients. Methods We have evaluated the pre and post treatment EEG, FDG-PET and detailed clinical behavioral and neuropsychometric test correlates of TMS in four CBD patients who were admitted to our dementia outpatient at the University of Medipol-Istanbul. The following detailed neuropsychometric test procedures were applied to patients; Digit Span (Forward/Back) Test, Verbal Fluency Test, Lexical Fluency Test, Clock Drawing Test, Similarities and Comprehension test, Verbal Learning Test (SBSTTA-Oktem), Wechsler Memory Scale (WMS-Logical Memory Test), Benton Face Recognition Test (BFR), Line Orientation Identification Test (BLOT), Neuropsychiatric Inventory (NPI), Geriatric Depression Scale (GDS), Frontal Behavioral Inventory Test (FBI), Standardized Mini Mental State Examination (MMSE) and Clinical Dementia Rating-Scale (CDR). Results & conclusion We have found that increased pretreatment theta activity was significantly decreased after the TMS treatment in frontal, central and parietal regions that was associated with the normalized glucose metabolism and neurobehavioral test scores after the TMS treatment.

try to identify central and peripheral markers related to emotional processes. Furthermore, the increased abilities of functional neural techniques have consistently favored the exploration of emotional components in health and in pathology. In this frame, the aim of this symposium is to bring together innovative researches integrating neurobehavioral data related to normal and dysregulated emotional reactivity. Consequently, the first (H. Sequeira, University of Lille, France) and second (B. Guntekin, Istanbul Kultur University, Turkey) speakers will illustrate the brain dynamic of affective pictures processing in healthy individuals by using magnetoencephalographic and oscillatory cerebral analyses. C. Baeken (Ghent University and University Hospital of Brussels, Belgium), through the application of repetitive Transcranial Magnetic Stimulation (rTMS), will show the potential importance of cingulate functional connectivity in treatment-resistant depression. J.M. Martinez-Selva (University of Murcia, Spain) will focus on the relevance of autonomic (the heart, electrodermal and respiratory activities) and somatic (corrugator supercilii activity) responses to understand mechanisms of neural and behavioral reactivity of persons with blood and snake phobia. J. Martineau (INSERM and University of Tours, France), thanks to behavioral (gaze patterns) and eye physiological indices (pupil diameter and blink rates), will show the interest of emotional static and dynamic faces analyses to explain the impaired social interaction in autistic pathology. In brief, by the original combination of psychophysiological tools in healthy and in behavioral disturbed individuals, this symposium will give an updated and prospective panorama of neurobehavioral exploration of emotion.

Objective Decreased delta event-related oscillations (ERO) have been reported in prior studies of Alzheimer’s disease (AD) and mild cognitive impairment (MCI); however no study has examined its utility in predicting disease progression. In this study, we examined the longitudinal changes in brain dynamics of MCI by using delta ERO and volumetric MRI (vMRI). Methods Twenty-two MCI and 23 matched control subjects were included. Peak-to-peak amplitudes of delta (0.5–3.5 Hz) auditory target ERO and vMRI were measured at baseline and a year later. The ERO and vMRI of stable and progressive MCI were compared. Results Decreased amplitudes of delta ERO were found in MCI for baseline and follow-up [F1.43 = 11.394, p = 0.002]. Progressive MCI had lower delta ERO than stable MCI at F3 electrode site at baseline. vMRI revealed that MCI had lower volumes at baseline in whole brain and left hippocampus, and at follow-up in whole brain, right and left hippocampi. Moreover, a moderate correlation was found between left hippocampus volumes and delta ERO at C4 electrode site. Conclusions These findings indicate that delta ERO may detect early changes in MCI and can be a useful tool to predict disease progression. Brain oscillatory responses have the potential to be used as biomarker in MCI.

Objective Parkinson’s disease (PD) is the second most common progressive neurodegenerative disorder which affects both motor and cognitive functioning. This study aims to investigate the sensory evoked oscillations (SEO) and event-related oscillations (ERO) of visual modality in cognitively normal PD patients and healthy controls. Methods Sixteen PD and 16 matched control subjects were participated to the study. Simple flashlight was used for SEO and a classical visual oddball paradigm was used for target ERO. Oscillatory responses in delta frequency range (0.5–3.0 Hz) were examined. Results Significant differences were found between groups on the maximum peak-to-peak amplitudes of both delta ERO and SEO responses [ F 1.27 = 8.573, p = 0.007; F 1.27 = 6.306, p = 0.018, respectively], indicating significantly lower delta responses in PD than healthy controls. Delta ERO responses were decreased in PD in frontal, central and parietal locations ( p Conclusions In this study, both target delta ERO and SEO responses were decreased in PD. According to the notion that the activity of sensory networks are reflected by SEO and cognitive networks by ERO, these findings indicate that PD patients have impairments in both networks of visual modality. Brain oscillatory responses have a potential to be searched as a biomarker for visual cognitive and sensory status of PD.

Aim of the report: In the companion report (Basar, this volume), the physiological fundaments of alpha activity in integrative brain function are described. The present report is a review of the significant role of alpha activity in memory and cognitive processes in healthy subjects, and in cognitive impairment. The role of neurotransmitters is also described, briefly, in this context. Towards an understanding of brain alpha: Despite numerous experimental studies, it is indicated that the presented results are only appropriate to establish an ensemble of reasonings and suggestions for analyzing "alphas" in the whole brain. In turn, in the near future, these reasonings and suggestions may serve (or are indispensable to serve) as fundaments of more general and tenable hypotheses on the genesis and function of "alphas". (C) 2012 Elsevier B.V. All rights

oscillatory activity, signifies the functional coupling of distributed brain regions involved in reward processing. Also, this provides support for the notion that two dissociable neural networks can be delineated for the processing of gains and losses (Yacubian et al., 2006). Based on the result that there was no effect of outcome probability on the thetaand beta-oscillations accordingly suggests that these oscillatory activities also may reflect an evaluation of outcomes on a shorter time scale in the learning process.

The present study describes electrophysiological differentiation of "Facial Expressions" by using the method of event-related oscillations (EROS). These measures were used to assess electrical manifestations of emotional expressions of 20 healthy subjects exposed to neutral, angry, and happy" faces. The present study extended previous analysis to frequency windows of delta (0.5-3.5 Hz) and theta (5-8.5 Hz) oscillations. No significant differences among responses to various face expression stimuli were observed, however, topological differences in response to all facial expressions were found. Delta oscillatory responses in the parietal-temporal-occipital locations were larger than the frontal and central locations, whereas theta oscillatory responses in the right temporal-occipital electrodes were larger than the right central electrodes. Assessment of topologically distributed multiple oscillations opens a new avenue for understanding of the electrophysiology of recognition of "faces" and "facial expressions". (c) 2008 Elsevier B.V. All rights reserved.

Comparatively analyses of electrophysiological correlates across species during evolution, alpha activity during brain maturation, and alpha activity in complex cognitive processes are presented to illustrate a new multidimensional "Cartesian System" brain function. The main features are: (1) The growth of the alpha activity during evolution, increase of alpha during cognitive processes, and decrease of the alpha entropy during evolution provide an indicator for evolution of brain cognitive performance. (2) Human children younger than 3 years are unable to produce higher cognitive processes and do not show alpha activity till the age of 3 years. The mature brain can perform higher cognitive processes and demonstrates regular alpha activity. (3) Alpha activity also is significantly associated with highly complex cognitive processes, such as the recognition of facial expressions. The neural activity reflected by these brain oscillations can be considered as constituent "building blocks" for a great number of functions. An overarching statement on the alpha function is presented by extended analyzes with multiple dimensions that constitute a "Cartesian Hyperspace" as the basis for oscillatory function. Theoretical implications are considered.