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Publication Open Access 1. Aile İşletmeleri Kongresi: Kongre Kitabı(İstanbul Kültür Üniversitesi, 2004-04) Koçel, Tamer; Eliaçık, MehtapPublication Open Access Önder ve Komutan Atatürk(İstanbul Kültür Üniversitesi, 2005) UCUZSATAR, NECATİ ULUNAY; ed., Cem AkbıyıkPublication Open Access 2. KOBİ’ler ve Verimlilik Kongresi(İstanbul Kültür Üniversitesi / İktisadi ve İdari Bilimler Fakültesi / İşletme Bölümü / KOBİ Danışma Birimi, 2005-12) Gençyılmaz, Güneş; Eliaçık, MehtapPublication Metadata only Principles of Oscillatory Brain Dynamics and a Treatise of recognition of Faces and Facial Expressions(ELSEVIER SCIENCE BV, SARA BURGERHARTSTRAAT 25, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2006) Öniz, Adile; BAŞAR, EROL; TR142226; TR204666; TR59951The research of event-related oscillations is one of fast-growing fields in neuroscience. In this study, a theory of the "whole-brain-work," which can be useful for functional interpretation of brain oscillations, is presented together with its application to recognition of faces and facial expressions. Following results are summarized: (1) Mechanisms leading to the perception of the grandmother picture are manifested with parallel activations of neural assemblies in different cortical locations and as superposition of delta, theta, alpha, beta, and gamma oscillations. Known and anonymous faces can be differentiated by means of oscillatory brain dynamics. Percepts cannot be localized in a given specific region. The differentiation of facial expression induces significant change in alpha and theta oscillation. (2) While the importance of fMRI in object recognition is clear, this method has low temporal resolution. Our results shows that multiple brain oscillations clearly differentiate the known and unknown faces with varied degrees of selective-responsiveness in a short time window between 0 and 800 ins, thus completing and implementing the analysis of percepts in the dynamic window and indicating a broader distribution at the cortex. (3) The presented evidence of selectively distributed multiple oscillations for differentiation of facial percepts is in conceptual accordance with the "selectively distributed processing" in neurocognitive networks of Goldman-Rakic, Fuster, and of Mesulam. The large-scale approach of several investigators is also confirmed with the new results. On facial stimuli, a given location can show a considerable selected activation, but the formation of percepts is manifested by multiple oscillations with differentiated weight in large neural populations. (4) The most important feature of the comparison of percepts of grandmother and anonymous faces is the existence of a variety of significant differences in delta, theta, alpha, beta, and gamma responses between the anonymous and grandmother faces in frontal, central, parietal, temporal, and occipital sites. (5) The brain response is a construct in a multi-dimensional state manifested by amplitudes of oscillatory responses, topological coordinates, and changes in the time axis following presentation of the percepts including delays and prolongations, coherence between locations. Only a new metrics embracing all these parameters can be representative for dynamics of functionality in the brain. The conceptual aspects of this new scope are explained in the presented theory.Publication Open Access 2. Aile İşletmeleri Kongresi: Kongre kitabı(İstanbul Kültür Üniversitesi / İktisadi ve İdari Bilimler Fakültesi / Aile İşletmeleri ve Girişimcilik Araştırma Merkezi, 2006-04) Koçel, Tamer; Eliaçık Gülaçtı, MehtapPublication Open Access 3. KOBİ’ler ve Verimlilik Kongresi(İstanbul Kültür Üniversitesi / İktisadi ve İdari Bilimler Fakültesi / İşletme Bölümü / KOBİ Danışma Birimi, 2006-11) Gençyılmaz, Güneş; Savcı Gökgöz, Gülsüm; Arıker, ÇağlaPublication Metadata only Emotional Face Expressions are Differentiated With Brain Oscillations(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2007-04) Güntekin, Bahar; BAŞAR, EROL; TR204666; TR142226The differentiation of "facial expressions" is a process of higher mental activity, which has considerable applications in "psychology of moods and emotions". We applied the approach of event-related oscillations (EROs) to investigate the modulation of electrical manifestations related to emotional expression in EEG recordings of 20 healthy subjects. EROs of "neutral, angry and happy" faces in 13 electrical recordings sites (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) were analyzed. Following the recording session, the subjects were asked to express the degree of their emotional involvement (valence and arousal) using the Self-Assessment Manikin ratings. Amplitude frequency characteristics (AFCs) were used to determine the frequencies of interest and the ranges for digital pass-band filtering applied accordingly. Consecutively, peak to peak amplitude measures of oscillatory responses were computed for the selected frequency bands and for the differentiation of the different stimuli. A differentiation between angry and happy facial expressions was observed especially in the alpha (9-13 Hz) and beta (15-24 Hz) frequencies, however, only when selecting stimuli with high mood involvement. Therefore, these frequency bands are the main focus of this report. The amplitudes of the alpha responses upon angry face stimulation were significantly higher than upon presentation of the happy faces at posterior locations. At F3, C, and C3, beta responses upon angry face stimulation were significantly higher in amplitude compared with the happy face stimulation. It is discussed that the frontal theta response is highly increased in comparison to all theta responses also encountered in studies of face recognition: During observation of facial expression, the occipital theta is much higher. We conclude and emphasize that the analysis of brain oscillatory responses distributed over the scalp in combination with subjective ratings of emotional impact of stimuli provide a good basis for analysing the influence of emotional information processing in the brain. In congruence with others, the results support the phylogenetical viewpoint suggesting that angry face stimulations are faster and more ample in responding. Furthermore, frontal, temporal, parietal and occipital lobes seem to be involved in processing of facial expressions, as reflected in an ensemble of different frequency brain oscillatory responses distributed over the scalp. (c) 2006 Published by Elsevier B.V.Publication Metadata only A breakthrough in neuroscience needs a "Nebulous Cartesian System" Oscillations, quantum dynamics and chaos in the brain and vegetative system(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2007-04) Güntekin, Bahar; BAŞAR, EROL; TR142226; TR204666The 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 modem 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 modem 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. (c) 2006 Published by Elsevier B.V.Publication Metadata only Brain Oscillations Differentiate the Picture of One's Own Grandmother(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2007-04) Özgören, Murat; Öniz, Adile; Schmiedt, Christina; Başar-Eroğlu, Canan; BAŞAR, EROL; TR142226; TR143075; TR59951; TR186954The present report introduces, as a first study, the concept and methods of oscillatory brain dynamics to analyze well-known (familiar) and unfamiliar face processing in the 800 ms following a face presentation. We analyzed event-related oscillations in young, healthy subjects (N=26) by using three types of stimulation: (1) a simple light signal, (2) the picture of the face of an anonymous elderly lady and (3) the picture of the subjects' own grandmother. We found a number of significant peak to peak amplitude measures in all frequency bands in the time period of 0-500 ms, allowing a differentiation between perception of the subjects' own grandmother, the unknown elderly face and the light stimulation. The results showed increased event-related oscillatory responses elicited by the unknown face compared to the known grandmother a) in the theta responses (4-8 Hz) at T-6 (46%), b) in the gamma (28-48 Hz) responses at C-z (22%) and C-3 (38%) and c) in the beta responses at F-4 (46%), C-z (47%) and P-3 (105%). In contrast, the subjects' own grandmother elicited 20% increased fast theta (6-8 Hz) oscillations at F-4 compared to the unknown face. Delta responses dissociated face from simple light processing, as reflected in the observation of approx. 50% higher amplitudes at the occipital compared to the frontal locations during face perception. We conclude that the described multiple brain oscillations clearly differentiate the known and unknown faces with varied degrees of selective-responsiveness in a short time window between 0 and 800 ms. Furthermore, the results are in conceptual accordance with the "selectively distributed processing" hypothesis. (c) 2006 Published by Elsevier B.V.Publication Metadata only Increased frontal phase-locking of event-related theta oscillations in Alzheimer patients treated with cholinesterase inhibitors(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2007-04) Yener, Görsev G.; Güntekin, Bahar; Öniz, Adile; BAŞAR, EROL; TR142226; TR143760; TR59951; TR204666This 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.Publication Metadata only Effect of valproate on oscillatory delta frequency responses to visual stimuli in a group of euthymic bipolar patients in comparison to healthy controls(Elsevier Science Inc, 360 Park Ave South, New York, Ny 10010-1710 USA, 2007-04-15) Özerdem, Ayşegül; Kocaaslan, Sibel; Tunca, Zeliha; BAŞAR, EROL; 140995; 12868; 143327; 142226Publication Metadata only Evolution of alpha activity and intuitive behaviour(Elsevier Science Inc, 360 Park Ave South, New York, Ny 10010-1710 USA, 2007-04-15) Güntekin, Bahar; BAŞAR, EROL; 142226; 204666Publication Metadata only Gender differences in recognition of facial expressions: Occipital beta oscillations of female subjects depict higher amplitudes(Elsevier Science Inc, 360 Park Ave South, New York, Ny 10010-1710 USA, 2007-04-15) Güntekin, Bahar; BAŞAR, EROL; 204666; 142226Publication Metadata only Brain oscillations are highly influenced by gender differences(ELSEVIER SCIENCE BV, PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS, 2007-09) Güntekin, Bahar; BAŞAR, EROL; TR204666; TR142226There 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.Publication Metadata only Gender Differences Influence Brain's Beta Oscillatory Responses in Recognition of Facial Expressions(ELSEVIER IRELAND LTD, ELSEVIER HOUSE, BROOKVALE PLAZA, EAST PARK SHANNON, CO, CLARE, 00000, IRELAND, 2007-09-07) Güntekin, Bahar; BAŞAR, EROL; TR142226; TR204666There are only few studies describing gender differences in recognition of facial expressions. Our study has the aim to analyze the effect of gender differences in oscillatory brain responses. Three sets of Ekman and Friesens's facial expressions (neutral, angry, and happy) were presented to 26 healthy subjects (13 men) while recording from 13 different scalp locations. Occipital beta response (15-24 Hz) was significantly larger for women than for men during the presentation of face expressions. Our results demonstrate that processing of emotional face expressions clearly differs between men and women. Accordingly, the results indicate the necessity of introducing standardization between male and female subjects by means of oscillatory dynamics. In turn, this standardization may be useful for cognitive and clinical studies. (C) 2007 Elsevier Ireland Ltd. All rights reserved.Publication Open Access 4. KOBİ’ler ve Verimlilik Kongresi(İstanbul Kültür Üniversitesi / İktisadi ve İdari Bilimler Fakültesi / İşletme Bölümü / KOBİ Danışma Birimi, 2007-12) Gençyılmaz, Güneş; Savcı Gökgöz, Gülsüm; Arıker, ÇağlaPublication Open Access 3. Aile İşletmeleri Kongresi: Kongre Kitabı(İstanbul Kültür Üniversitesi / İktisadi ve İdari Bilimler Fakültesi / Aile İşletmeleri ve Girişimcilik Araştırma Merkezi, 2008-04) Koçel, Tamer; Eliaçık Gülaçtı, MehtapPublication Metadata only Event related oscillations during recognition of face expressions(Elsevier Science Inc, 360 Park Ave South, New York, Ny 10010-1710 USA, 2008-04-01) Güntekin, Bahar; BAŞAR, EROL; 142226; 204666Publication Metadata only High occipital beta (18-30 Hz) and low occipital alpha (8-13 Hz) oscillatory response to target visual stimuli in bipolar disorder reduce with chronic valproate use(Elsevier Science Inc, 360 Park Ave South, New York, Ny 10010-1710 USA, 2008-04-01) Özerdem, Ayşegül; Güntekin, Bahar; Tunca, Zeliha; BAŞAR, EROL; 140995; 204666; 143327; 142226Publication Metadata only Event related oscillations differentiate the face of the loved person from other faces(Elsevier Science Inc, 360 Park Ave South, New York, Ny 10010-1710 USA, 2008-04-01) Schmiedt-Fehr, Christina; Öniz, Adile; Başar Eroğlu, Canan; BAŞAR, EROL; 142226; 59951