scholarly journals Visual Stimulus–Dependent Changes in Interhemispheric EEG Coherence in Humans

1999 ◽  
Vol 82 (6) ◽  
pp. 3095-3107 ◽  
Author(s):  
M. G. Knyazeva ◽  
D. C. Kiper ◽  
V. Y. Vildavski ◽  
P. A. Despland ◽  
M. Maeder-Ingvar ◽  
...  
Keyword(s):  
Animal Studies ◽  
Human Subjects ◽  
Visual Stimuli ◽  
Eeg Coherence ◽  
Eeg Signals ◽  
Vertical Meridian ◽  
Gamma Frequency ◽  
Within Subjects ◽  
The Many ◽  
Cortical Connection

We analyzed the coherence of electroencephalographic (EEG) signals recorded symmetrically from the two hemispheres, while subjects ( n = 9) were viewing visual stimuli. Considering the many common features of the callosal connectivity in mammals, we expected that, as in our animal studies, interhemispheric coherence (ICoh) would increase only with bilateral iso-oriented gratings located close to the vertical meridian of the visual field, or extending across it. Indeed, a single grating that extended across the vertical meridian significantly increased the EEG ICoh in normal adult subjects. These ICoh responses were obtained from occipital and parietal derivations and were restricted to the gamma frequency band. They were detectable with different EEG references and were robust across and within subjects. Other unilateral and bilateral stimuli, including identical gratings that were effective in anesthetized animals, did not affect ICoh in humans. This fact suggests the existence of regulatory influences, possibly of a top-down kind, on the pattern of callosal activation in conscious human subjects. In addition to establishing the validity of EEG coherence analysis for assaying cortico-cortical connectivity, this study extends to the human brain the finding that visual stimuli cause interhemispheric synchronization, particularly in frequencies of the gamma band. It also indicates that the synchronization is carried out by cortico-cortical connection and suggests similarities in the organization of visual callosal connections in animals and in man.

’Animal Studies‘, Disziplinarität und die (Post-)Humanities

2013 ◽  
Vol 4 (1) ◽  
Author(s):  
Cary Wolfe
Keyword(s):  
Social Communication ◽  
Animal Studies ◽  
Human Subjects

Der Text von Cary Wolfe ist eine gekürzte Übersetzung des Kapitels »Animal Studies«, Disciplinarity, and the (Post)Humanities aus der Monographie What is Posthumanism? (Minnesota 2009). Wolfe diskutiert die Beziehung zwischen (Trans-)Disziplinarität und Posthumanismus im Rückgriff auf Konzepte von Derrida, Foucault und Luhmann, die eine Form von gesellschaftlicher Kommunikation zu denken erlauben, an der menschliche Subjekte zwar noch teilhaben, aber deren souveräne Urheber sie nicht mehr sind </br></br>The paper by Cary Wolfe is an abridged translation of the chapter »Animal Studies«, Disciplinarity, and the (Post)Humanities from the monograph (Minnesota 2009). Wolfe discusses the relation between (trans-)disciplinarity and posthumanism with reference to concepts by Derrida, Foucault and Luhmann, allowing to consider a form of social communication in which human subjects still may participate, but no longer are their sovereign initiators.

Development of the Biostator Glucose clamping algorithm.

1982 ◽  
Vol 28 (9) ◽  
pp. 1899-1904 ◽  
Author(s):  
A H Clemens ◽  
D L Hough ◽  
P A D'Orazio
Keyword(s):  
Animal Studies ◽  
Insulin Infusion ◽  
Blood Glucose Concentration ◽  
Human Subjects ◽  
Pancreatic Beta Cell ◽  
Model System ◽  
Exogenous Insulin ◽  
Maturity Onset Diabetes ◽  
Beta Cell Response ◽  
Infusion System

Abstract The "glucose clamping" technique has been proposed as a method for the early detection of a beginning derangement of glucose homeostasis and thus for the possible prevention of maturity-onset diabetes. This technique interrupts the physiological glucose-insulin relationship by placing a patient's blood glucose concentration under an investigator's control, for quantification of the pancreatic beta-cell response during hyperglycemic clamps and of sensitivity of body tissue to exogenous insulin during normoglycemic clamps. We report the development of a glucose clamping algorithm for use with the Biostator glucose-controlled insulin-infusion system (Horm. Metab. Res., Suppl. 8: 23-33, 1977). This algorithm adds simplicity and precision to the glucose clamping procedure and reduces operator effort to a minimum. We describe the early development of the algorithm with a model system and report evaluations made during animal studies and preliminary investigations with human subjects.

scholarly journals Nutritional programming of gastrointestinal tract development. Is the pig a good model for man?

2010 ◽  
Vol 23 (1) ◽  
pp. 4-22 ◽  
Author(s):  
Paul Guilloteau ◽  
Romuald Zabielski ◽  
Harald M. Hammon ◽  
Cornelia C. Metges
Keyword(s):  
Gastrointestinal Tract ◽  
Animal Models ◽  
Animal Studies ◽  
Reference Model ◽  
Human Subjects ◽  
Mammalian Species ◽  
Epidemiological Studies ◽  
Long Term Effects ◽  
Nutritional Programming ◽  
The Impact

The consequences of early-life nutritional programming in man and other mammalian species have been studied chiefly at the metabolic level. Very few studies, if any, have been performed in the gastrointestinal tract (GIT) as the target organ, but extensive GIT studies are needed since the GIT plays a key role in nutrient supply and has an impact on functions of the entire organism. The possible deleterious effects of nutritional programming at the metabolic level were discovered following epidemiological studies in human subjects, and confirmed in animal models. Investigating the impact of programming on GIT structure and function would need appropriate animal models due to ethical restrictions in the use of human subjects. The aim of the present review is to discuss the use of pigs as an animal model as a compromise between ethically acceptable animal studies and the requirement of data which can be interpolated to the human situation. In nutritional programming studies, rodents are the most frequently used model for man, but GIT development and digestive function in rodents are considerably different from those in man. In that aspect, the pig GIT is much closer to the human than that of rodents. The swine species is closely comparable with man in many nutritional and digestive aspects, and thus provides ample opportunity to be used in investigations on the consequences of nutritional programming for the GIT. In particular, the ‘sow–piglets’ dyad could be a useful tool to simulate the ‘human mother–infant’ dyad in studies which examine short-, middle- and long-term effects and is suggested as the reference model.

scholarly journals Statistical Model-Based Classification to Detect Patient-Specific Spike-and-Wave in EEG Signals

2020 ◽  
Author(s):  
Antonio Quintero Rincón ◽  
Hadj Batatia ◽  
Jorge Prende ◽  
Valeria Muro ◽  
Carlos D'Giano
Keyword(s):  
Statistical Model ◽  
Human Subjects ◽  
True Positive Rate ◽  
Wave Pattern ◽  
Absence Epilepsy ◽  
Patient Specific ◽  
Eeg Signals ◽  
True Negative ◽  
Eeg Recordings

Spike-and-wave discharge (SWD) pattern detection in electroencephalography (EEG) signals is a key signal processing problem. It is particularly important for overcoming time-consuming, difficult, and error-prone manual analysis of long-term EEG recordings. This paper presents a new SWD method with a low computational complexity that can be easily trained with data from standard medical protocols. Precisely, EEG signals are divided into time segments for which the Morlet 1-D decomposition is applied. The generalized Gaussian distribution (GGD) statistical model is fitted to the resulting wavelet coefficients. A k-nearest neighbors (k-NN) self-supervised classifier is trained using the GGD parameters to detect the spike-and-wave pattern. Experiments were conducted using 106 spike-and-wave signals and 106 non-spike-and-wave signals for training and another 96 annotated EEG segments from six human subjects for testing. The proposed SWD classification methodology achieved 95 % sensitivity (True positive rate), 87% specificity (True Negative Rate), and 92% accuracy. These results set the path to new research to study causes underlying the so-called absence epilepsy in long-term EEG recordings.

scholarly journals Melissa officinalis L. as a Nutritional Strategy for Cardioprotection

2021 ◽  
Vol 12 ◽  
Author(s):  
Nevena Draginic ◽  
Vladimir Jakovljevic ◽  
Marijana Andjic ◽  
Jovana Jeremic ◽  
Ivan Srejovic ◽  
...  
Keyword(s):  
Essential Oil ◽  
Animal Studies ◽  
Human Subjects ◽  
Radical Scavenging ◽  
Cardiovascular Effects ◽  
Melissa Officinalis ◽  
Active Components ◽  
Protective Mechanisms ◽  
Voltage Dependent ◽  
Radical Scavenging Properties

This review aimed to provide a summary on the traditional uses, phytochemistry, and pharmacological activities in the cardiovascular system and cardiotoxicity of Melissa officinalis (MO), with the special emphasis on the protective mechanisms in different cardiovascular pathologies. MO is a perennial aromatic herb commonly known as lemon balm, honey balm, or bee balm, which belongs to Lamiaceae family. Active components are mainly located in the leaves or essential oil and include volatile compounds, terpenoid (monoterpenes, sesquiterpenes, triterpenes), and polyphenolic compounds [rosmarinic acid (RA), caffeic acid, protocatechuic acid, quercitrin, rhamnocitrin, luteolin]. For centuries, MO has been traditionally used as a remedy for memory, cognition, anxiety, depression, and heart palpitations. Up until now, several beneficial cardiovascular effects of MO, in the form of extracts (aqueous, alcoholic, and hydroalcoholic), essential oil, and isolated compounds, have been confirmed in preclinical animal studies, such as antiarrhythmogenic, negative chronotropic and dromotropic, hypotensive, vasorelaxant, and infarct size–reducing effects. Nonetheless, MO effects on heart palpitations are the only ones confirmed in human subjects. The main mechanisms proposed for the cardiovascular effects of this plant are antioxidant free radical–scavenging properties of MO polyphenols, amelioration of oxidative stress, anti-inflammatory effects, activation of M2 and antagonism of β1 receptors in the heart, blockage of voltage-dependent Ca2+ channels, stimulation of endothelial nitric oxide synthesis, prevention of fibrotic changes, etc. Additionally, the main active ingredient of MO-RA, per se, has shown substantial cardiovascular effects. Because of the vastness of encouraging data from animal studies, this plant, as well as the main ingredient RA, should be considered and investigated further as a tool for cardioprotection and adjuvant therapy in patients suffering from cardiovascular diseases.

scholarly journals Nutrition and its contribution to obesity and diabetes: a life-course approach to disease prevention?

2008 ◽  
Vol 68 (1) ◽  
pp. 71-77 ◽  
Author(s):  
Michael E. Symonds
Keyword(s):  
Animal Studies ◽  
Dietary Intervention ◽  
Human Subjects ◽  
Disease Onset ◽  
Small Animal ◽  
Extended Period ◽  
Major Influence ◽  
Relative Contribution ◽  
Obesity And Diabetes

Whilst previously type 2 diabetes occurred in older adults, its incidence, together with obesity, has increased rapidly in children. An improved understanding of this disease pathway from a developmental view point is critical. It is likely that subtle changes in dietary patterns over an extended period of time contribute to diabetes, although this type of rationale is largely ignored in animal studies aimed at determining the mechanisms involved. Small-animal studies in which large, and often extreme, changes in the diet are imposed at different stages of the life cycle can have substantial effects on fat mass and/or pancreatic functions. These responses are not representative of the much more gradual changes seen in the human population. An increasing number of studies indicate that it is growth rate per se, rather than the type of dietary intervention that determines pancreatic function during development. Epigenetic mechanisms that regulate insulin secretion by the pancreas can be re-set by more extreme changes in dietary supply in early life. The extent to which these changes may contribute to more subtle modulations in glucose homeostasis that can accompany excess fat growth in childhood remains to be established. For human subjects there is much less information as to whether specific dietary components determine disease onset. Indeed, it is highly likely that genotype has a major influence, although recent data relating early diet to physical activity and the FTO gene indicate the difficulty of establishing the relative contribution of diet and changes in body mass to diabetes.

scholarly journals Dark matters: effects of light at night on metabolism

2018 ◽  
Vol 77 (3) ◽  
pp. 223-229 ◽  
Author(s):  
Randy J. Nelson ◽  
Souhad Chbeir
Keyword(s):  
Circadian Rhythms ◽  
Animal Studies ◽  
Human Subjects ◽  
Night Shift ◽  
Past Century ◽  
Light At Night ◽  
Shift Workers ◽  
The Past ◽  
Time Of Year ◽  
Life On Earth

Life on earth has evolved during the past several billion years under relatively bright days and dark night conditions. The wide-spread adoption of electric lights during the past century exposed animals, both human and non-human, to significant light at night for the first time in their evolutionary history. Endogenous circadian clocks depend on light to entrain to the external daily environment and seasonal rhythms depend on clear nightly melatonin signals to assess time of year. Thus, light at night can derange temporal adaptations. Indeed, disruption of naturally evolved light–dark cycles results in several physiological and behavioural changes with potentially serious implications for physiology, behaviour and mood. In this review, data from night-shift workers on their elevated risk for metabolic disorders, as well as data from animal studies will be discussed. Night-shift workers are predisposed to obesity and dysregulated metabolism that may result from disrupted circadian rhythms. Although studies in human subjects are correlative, animal studies have revealed several mechanisms through which light at night may exert its effects on metabolism by disrupting circadian rhythms that are associated with inflammation, both in the brain and in the periphery. Disruption of the typical timing of food intake is a key effect of light at night and subsequent metabolic dysregulation. Strategies to avoid the effects of light at night on body mass dysregulation should be pursued.

Information-based Analysis of the Coupling between Dynamic Visual Stimuli, Eye Movements, and Brain Signals

2021 ◽  
pp. 2150048
Author(s):  
Hamidreza Namazi ◽  
Avinash Menon ◽  
Ondrej Krejcar
Keyword(s):  
Eye Movements ◽  
Moving Objects ◽  
Brain Activity ◽  
Visual Stimuli ◽  
Strongly Correlated ◽  
Eeg Signals ◽  
Vision Science ◽  
Brain Signals ◽  
Information Contents ◽  
The Brain

Our eyes are always in search of exploring our surrounding environment. The brain controls our eyes’ activities through the nervous system. Hence, analyzing the correlation between the activities of the eyes and brain is an important area of research in vision science. This paper evaluates the coupling between the reactions of the eyes and the brain in response to different moving visual stimuli. Since both eye movements and EEG signals (as the indicator of brain activity) contain information, we employed Shannon entropy to decode the coupling between them. Ten subjects looked at four moving objects (dynamic visual stimuli) with different information contents while we recorded their EEG signals and eye movements. The results demonstrated that the changes in the information contents of eye movements and EEG signals are strongly correlated ([Formula: see text]), which indicates a strong correlation between brain and eye activities. This analysis could be extended to evaluate the correlation between the activities of other organs versus the brain.

scholarly journals Prediction of Visual Memorability with EEG Signals: A Comparative Study

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2694
Author(s):  
Sang-Yeong Jo ◽  
Jin-Woo Jeong
Keyword(s):  
Visual Memory ◽  
Human Subjects ◽  
Memory Task ◽  
Support Vector ◽  
Classification Models ◽  
Biological Feedback ◽  
Eeg Signals ◽  
Deep Convolutional Neural Networks ◽  
K Nearest Neighbors ◽  
Visual Memory Task

Visual memorability is a method to measure how easily media contents can be memorized. Predicting the visual memorability of media contents has recently become more important because it can affect the design principles of multimedia visualization, advertisement, etc. Previous studies on the prediction of the visual memorability of images generally exploited visual features (e.g., color intensity and contrast) or semantic information (e.g., class labels) that can be extracted from images. Some other works tried to exploit electroencephalography (EEG) signals of human subjects to predict the memorability of text (e.g., word pairs). Compared to previous works, we focus on predicting the visual memorability of images based on human biological feedback (i.e., EEG signals). For this, we design a visual memory task where each subject is asked to answer whether they correctly remember a particular image 30 min after glancing at a set of images sampled from the LaMemdataset. During the visual memory task, EEG signals are recorded from subjects as human biological feedback. The collected EEG signals are then used to train various classification models for prediction of image memorability. Finally, we evaluate and compare the performance of classification models, including deep convolutional neural networks and classical methods, such as support vector machines, decision trees, and k-nearest neighbors. The experimental results validate that the EEG-based prediction of memorability is still challenging, but a promising approach with various opportunities and potentials.

scholarly journals Institutional Review Board and International Field Research in Conflict Zones

2014 ◽  
Vol 47 (04) ◽  
pp. 840-844 ◽  
Author(s):  
Srobana Bhattacharya
Keyword(s):  
Human Subjects ◽  
Social Science Research ◽  
Field Research ◽  
Science Research ◽  
Political Conflict ◽  
Institutional Review Board ◽  
Biomedical Sciences ◽  
Conflict Zones ◽  
Institutional Review ◽  
The Many

ABSTRACTResearch on political conflict can benefit immensely from fieldwork. However, the Institutional Review Board (IRB) process is elaborate and daunting that discourages rather than encourages this type of research. Existing policies often are insensitive to the many uncertainties related to field research abroad, especially in conflict zones. Three reasons for this are identified in this article. First, the federal regulations to protect human subjects of social science research are most suitable for biomedical sciences. Second, there is huge gap between “procedural ethics” and “ethics in practice.” Third, there is a lack of communication or dialogue between researchers and IRBs. After discussing these reasons, I offer the following suggestions: bridging the gap between the researcher and the IRB; reducing delays in the IRB approval and revision process; encouraging collaboration and dialogue among researchers; and advocating a proactive stance by academic associations.

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