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Cognitive Neurodynamics

Yesim Güzey Aras, Abdülkadir Tunç, Belma Doğan Güngen, Adil Can Güngen, Yusuf Aydemir, Bekir Enes Demiyürek
The purpose of this study was to investigate the effects of depression, anxiety and sleep disturbances on cognitive functions in chronic obstructive pulmonary disease (COPD) patients. In this prospective case-control study, demographic data, smoking history, depression, anxiety, sleep quality and cognitive status of 48 COPD patients and 36 healthy volunteers aged 40-90 years were recorded. The Beck depression inventory (BDI), the Beck anxiety inventory (BAI), and Pittsburgh Sleep Quality Index (PSQI) were used to assess depression, anxiety and sleep quality, respectively in COPD patients...
December 2017: Cognitive Neurodynamics
Jingyi Qu, Rubin Wang
In this paper, the collective behaviors of a small-world neuronal network motivated by the anatomy of a mammalian cortex based on both Izhikevich model and Rulkov model are studied. The Izhikevich model can not only reproduce the rich behaviors of biological neurons but also has only two equations and one nonlinear term. Rulkov model is in the form of difference equations that generate a sequence of membrane potential samples in discrete moments of time to improve computational efficiency. These two models are suitable for the construction of large scale neural networks...
December 2017: Cognitive Neurodynamics
Eva Déli, Arturo Tozzi, James F Peters
Brain electric activity exhibits two important features: oscillations with different timescales, characterized by diverse functional and psychological outcomes, and a temporal power law distribution. In order to further investigate the relationships between low- and high- frequency spikes in the brain, we used a variant of the Borsuk-Ulam theorem which states that, when we assess the nervous activity as embedded in a sphere equipped with a fractal dimension, we achieve two antipodal points with similar features (the slow and fast, scale-free oscillations)...
December 2017: Cognitive Neurodynamics
Dongzhe Hou, Chunfang Wang, Yuanyuan Chen, Weijie Wang, Jingang Du
Abnormal long-range temporal correlation (LRTC) in EEG oscillation has been observed in several brain pathologies and mental disorders. This study examined the relationship between the LRTC of broadband EEG oscillation and depression following cerebral infarction with different hemispheric lesions to provide a novel insight into such depressive disorders. Resting EEGs of 16 channels in 18 depressed (9 left and 9 right lesions) and 21 non-depressed (11 left and 10 right lesions) subjects following cerebral infarction and 19 healthy control subjects were analysed by means of detrended fluctuation analysis, a quantitative measurement of LRTC...
December 2017: Cognitive Neurodynamics
Jong Ho Hwang, Kyoung Won Nam, Dong Pyo Jang, In Young Kim
There have been few reports that investigated the effects of the degree and pattern of a spectral smearing of stimuli due to deteriorated hearing ability on the performance of auditory brain-computer interface (BCI) systems. In this study, we assumed that such spectral smearing of stimuli may affect the performance of an auditory steady-state response (ASSR)-based BCI system and performed subjective experiments using 10 normal-hearing subjects to verify this assumption. We constructed smearing-reflected stimuli using an 8-channel vocoder with moderate and severe hearing loss setups and, using these stimuli, performed subjective concentration tests with three symmetric and six asymmetric smearing patterns while recording electroencephalogram signals...
December 2017: Cognitive Neurodynamics
A Khasnobish, S Datta, R Bose, D N Tibarewala, A Konar
Tactual exploration of objects produce specific patterns in the human brain and hence objects can be recognized by analyzing brain signals during tactile exploration. The present work aims at analyzing EEG signals online for recognition of embossed texts by tactual exploration. EEG signals are acquired from the parietal region over the somatosensory cortex of blindfolded healthy subjects while they tactually explored embossed texts, including symbols, numbers, and alphabets. Classifiers based on the principle of supervised learning are trained on the extracted EEG feature space, comprising three features, namely, adaptive autoregressive parameters, Hurst exponents, and power spectral density, to recognize the respective texts...
December 2017: Cognitive Neurodynamics
Yasar Dasdemir, Esen Yildirim, Serdar Yildirim
In this study, we investigate the brain networks during positive and negative emotions for different types of stimulus (audio only, video only and audio + video) in [Formula: see text], and [Formula: see text] bands in terms of phase locking value, a nonlinear method to study functional connectivity. Results show notable hemispheric lateralization as phase synchronization values between channels are significant and high in right hemisphere for all emotions. Left frontal electrodes are also found to have control over emotion in terms of functional connectivity...
December 2017: Cognitive Neurodynamics
Csaba Kerepesi, Balázs Szalkai, Bálint Varga, Vince Grolmusz
Based on the data of the NIH-funded Human Connectome Project, we have computed structural connectomes of 426 human subjects in five different resolutions of 83, 129, 234, 463 and 1015 nodes and several edge weights. The graphs are given in anatomically annotated GraphML format that facilitates better further processing and visualization. For 96 subjects, the anatomically classified sub-graphs can also be accessed, formed from the vertices corresponding to distinct lobes or even smaller regions of interests of the brain...
October 2017: Cognitive Neurodynamics
Xiaoqing Li, Yuping Zhang, Lin Li, Haiyan Zhao, Xiufang Du
The present electroencephalogram study used an attention probe paradigm to investigate how semantic and acoustic structures constrain temporal attention during speech comprehension. Spoken sentences were used as stimuli, with each one containing a four-character critical phrase, of which the third character was the target character. We manipulated not only the semantic relationship between the target character and the immediately preceding two characters, but also the presence/absence of a pitch accent on the first character...
October 2017: Cognitive Neurodynamics
Zhiyong Yang, Taohong Zhang, Jingcheng Lu, Yuan Su, Dezheng Zhang, Yaowu Duan
This paper studies the joint effect of V-matrix, a recently proposed framework for statistical inferences, and extreme learning machine (ELM) on regression problems. First of all, a novel algorithm is proposed to efficiently evaluate the V-matrix. Secondly, a novel weighted ELM algorithm called V-ELM is proposed based on the explicit kernel mapping of ELM and the V-matrix method. Though V-matrix method could capture the geometrical structure of training data, it tends to assign a higher weight to instance with smaller input value...
October 2017: Cognitive Neurodynamics
Zhuosheng Lü, Bizhao Zhang, Lixia Duan
Experimental investigations have shown that the pre-Bötzinger complex (pre-BötC) within the mammalian brainstem generates the inspiratory phase of respiratory rhythm. Based on a single-compartment model of a pre-BötC inspiratory neuron, we, in this paper, use semi-analytical, numerical as well as fast-slow dynamical methods to investigate the effects of sodium conductance ([Formula: see text]) and potassium conductance ([Formula: see text]) on the firing activities of pre-BötC and try to reveal the dynamical mechanisms behind them...
October 2017: Cognitive Neurodynamics
Nicolas Rouleau, Nirosha J Murugan, Michael A Persinger
Post-mortem human neural tissues fixed in ethanol and aldehyde-based solutions express modulated frequency-dependent microvolt potentials when probed by chemical and electrical stimuli. These observations run contrary to the assumption that basic tissue functions are irreversibly impaired upon fixation, in the absence of nutrients and sufficient concentrations of physiological ions. The aim of the current study was to investigate the relative effects of pH and specific charged particles relevant to normal cell physiology upon electric potentials associated with fixed post-mortem rat brain tissue...
October 2017: Cognitive Neurodynamics
Hui Wei, Yijie Bu, Dawei Dai
To adapt to the environment and survive, most animals can control their behaviors by making decisions. The process of decision-making and responding according to cues in the environment is stable, sustainable, and learnable. Understanding how behaviors are regulated by neural circuits and the encoding and decoding mechanisms from stimuli to responses are important goals in neuroscience. From results observed in Drosophila experiments, the underlying decision-making process is discussed, and a neural circuit that implements a two-choice decision-making model is proposed to explain and reproduce the observations...
October 2017: Cognitive Neurodynamics
Sang-Yoon Kim, Woochang Lim
For studying how dynamical responses to external stimuli depend on the synaptic-coupling type, we consider two types of excitatory and inhibitory synchronization (i.e., synchronization via synaptic excitation and inhibition) in complex small-world networks of excitatory regular spiking (RS) pyramidal neurons and inhibitory fast spiking (FS) interneurons. For both cases of excitatory and inhibitory synchronization, effects of synaptic couplings on dynamical responses to external time-periodic stimuli S(t) (applied to a fraction of neurons) are investigated by varying the driving amplitude A of S(t)...
October 2017: Cognitive Neurodynamics
James F Peters, Arturo Tozzi, Sheela Ramanna, Ebubekir İnan
Contrary to common belief, the brain appears to increase the complexity from the perceived object to the idea of it. Topological models predict indeed that: (a) increases in anatomical/functional dimensions and symmetries occur in the transition from the environment to the higher activities of the brain, and (b) informational entropy in the primary sensory areas is lower than in the higher associative ones. To demonstrate this novel hypothesis, we introduce a straightforward approach to measuring island information levels in fMRI neuroimages, via Rényi entropy derived from tessellated fMRI images...
August 2017: Cognitive Neurodynamics
Shi Jiancheng, Luo Min, Huang Chusheng
The cooperative effect of random coupling strength and time-periodic coupling strengh on synchronization transitions in one-way coupled neural system has been investigated by mean field approach. Results show that cooperative coupling strength (CCS) plays an active role for the enhancement of synchronization transitions. There exist an optimal frequency of CCS which makes the system display the best CCS-induced synchronization transitions, a critical frequency of CCS which can not further affect the CCS-induced synchronization transitions, and a critical amplitude of CCS which can not occur the CCS-induced synchronization transitions...
August 2017: Cognitive Neurodynamics
S Dharani, R Rakkiyappan, Jinde Cao, Ahmed Alsaedi
This paper explores the problem of synchronization of a class of generalized reaction-diffusion neural networks with mixed time-varying delays. The mixed time-varying delays under consideration comprise of both discrete and distributed delays. Due to the development and merits of digital controllers, sampled-data control is a natural choice to establish synchronization in continuous-time systems. Using a newly introduced integral inequality, less conservative synchronization criteria that assure the global asymptotic synchronization of the considered generalized reaction-diffusion neural network and mixed delays are established in terms of linear matrix inequalities (LMIs)...
August 2017: Cognitive Neurodynamics
Bahar Güntekin, Banu Femir, Bilge Turp Gölbaşı, Elif Tülay, Erol Başar
Analysis of affective picture processing by means of EEG has invaded the literature. The methodology of event-related EEG coherence is one of the essential methods used to analyze functional connectivity. The aims of the present study are to find out the long range EEG connectivity changes in perception of different affective pictures and analyze gender differences in these long range connected networks. EEGs of 28 healthy subjects (14 female) were recorded at 32 locations. The participants passively viewed emotional pictures (IAPS, unpleasant, pleasant, neutral)...
August 2017: Cognitive Neurodynamics
Pierre Bonzon
A computational architecture modeling the relation between perception and action is proposed. Basic brain processes representing synaptic plasticity are first abstracted through asynchronous communication protocols and implemented as virtual microcircuits. These are used in turn to build mesoscale circuits embodying parallel cognitive processes. Encoding these circuits into symbolic expressions gives finally rise to neuro-inspired programs that are compiled into pseudo-code to be interpreted by a virtual machine...
August 2017: Cognitive Neurodynamics
Fatemeh Bakouie, Morteza Pishnamazi, Roxana Zeraati, Shahriar Gharibzadeh
When two eyes are simultaneously stimulated by two inconsistent images, the observer's perception switches between the two images every few seconds such that only one image is perceived at a time. This phenomenon is named binocular rivalry (BR). However, sometimes the perceived image is a piecemeal mixed of two stimuli known as piecemeal perceptions. In this study, a BR task was designed in which orthogonal gratings are presented to the two eyes. The subjects were trained to report 3 states: dominant perceptions (two state matching to perceived grating orientation) and the piecemeal perceptions (third state)...
August 2017: Cognitive Neurodynamics
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