Search Results
Results 1 - 50 of 681
1 2 3 4 5 6 7 8 9 10 >
Ali Fadel M FM Biophysics Department, Faculty of Science, Cairo University, - - 2014
Typhoid is a serious disease difficult to be treated with conventional drugs. The aim of the present work was to demonstrate a new method for the control of Salmonella.typhi growth, through the interference with the bioelectric signals generated from the microbe during cell division by extremely low frequency electromagnetic waves ...
Haughton Pippa N - - 2012
Campylobacter is an important cause of human gastroenteritis worldwide. Chicken meat is frequently contaminated with this organism and is considered to be a significant source of infection. It has been predicted that lowering the numbers of Campylobacter on chicken meat can reduce the risk to public health. The aims of ...
Shafiei S A - - 2012
It has been reported that human subjects exposed to electromagnetic fields exhibit changes in human EEG signals at the frequency of stimulation. The aim of the present study was to expose different parts of the brain to extremely low-frequency magnetic fields locally and investigate EEG power spectrum alters at the ...
Yin Zhengmao - - 2012
A remarkable enhancement of light extraction efficiency in GaN-based blue light-emitting diodes (LEDs) with rough beveled ZnO nanocone arrays grown on the planar indium tin oxide (ITO) layer is reported. The light output power of LEDs with rough beveled ZnO nanocone arrays was increased by about 110% at 20 mA ...
Ikegami Tsuyoshi - - 2012
Movement error is a driving force behind motor learning. For motor learning with discrete movements, such as point-to-point reaching, it is believed that the brain uses error information of the immediately preceding movement only. However, in the case of continuous and repetitive movements (i.e., rhythmic movements), there is a ceaseless ...
Saunders John A JA Translational Neuroscience Program, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, - - 2012
There is increasing evidence that functional deficits in schizophrenia may be driven by a reduction in the signal-to-noise ratio (SNR) and consistent timing of neural signals. This study examined the extent to which exposure to the NMDA receptor antagonists ketamine and MK801, frequently used pharmacological models of schizophrenia, recreate deficits ...
Glass J David - - 2012
Cocaine abuse is highly disruptive to circadian physiological and behavioral rhythms. The present study was undertaken to determine whether such effects are manifest through actions on critical photic and nonphotic regulatory pathways in the master circadian clock of the mouse suprachiasmatic nucleus (SCN). Impairment of SCN photic signaling by systemic ...
Pinton Gianmarco - - 2012
Purpose: Therapeutic ultrasound has been used in the brain for thrombolysis and high intensity focused ultrasound (HIFU) therapy. A low-frequency clinical study of sonothrombolysis, called the transcranial low-frequency ultrasound-mediated thrombolysis in brain ischemia (TRUMBI), has revealed an increased incidence of hemorrhage, which may have been caused by cavitation. The goal ...
Anderson Barton L - - 2011
The visual system relies on patterns of light to provide information about the layout of objects that populate our environment. Light is structured by the way it interacts with the three-dimensional shape, reflectance, and transmittance properties of objects. The input for vision is therefore a complex, conflated mixture of different ...
Weir Peter T - - 2011
Insects maintain a constant bearing across a wide range of spatial scales. Monarch butterflies and locusts traverse continents [1, 2], and foraging bees and ants travel hundreds of meters to return to their nests [1, 3, 4], whereas many other insects fly straight for only a few centimeters before changing ...
Bernasconi Fosco - - 2011
Behavioral and brain responses to identical stimuli can vary with experimental and task parameters, including the context of stimulus presentation or attention. More surprisingly, computational models suggest that noise-related random fluctuations in brain responses to stimuli would alone be sufficient to engender perceptual differences between physically identical stimuli. In two ...
Rosa Salva Orsola - - 2011
A spontaneous preference for face-like stimuli has been demonstrated in domestic chicks, similar to that shown by human newborns, suggesting evolutionary continuity across species. Inversion of contrast polarity of face-like stimuli abolishes face preferences in human newborns. Here we investigated the effects of contrast polarity inversion and brain lateralization in ...
Wei Hongying - - 2011
Pigment-dispersing factor-immunoreactive neurons anterior to the accessory medulla (aPDFMes) in the optic lobes of insects are circadian pacemaker neurons in cockroaches and fruit flies. The authors examined whether any of the aPDFMes of the cockroach Leucophaea maderae are sensitive to changes in period and photoperiod of light/dark (LD) cycles as ...
Hawkins Robert D RD Department of Neuroscience, Columbia University, New York, NY 10032, USA. - - 2011
A good deal is known about psychological factors that contribute to reward value, but very little is known about how reward is computed in the brain. Integration in the circuit for brain stimulation reward may provide a simple model system. Parametric studies have favored the idea that the integration is ...
Wuerger Sophie M - - 2011
The auditory and visual perception systems have developed special processing strategies for ecologically valid motion stimuli, utilizing some of the statistical properties of the real world. A well-known example is the perception of biological motion, for example, the perception of a human walker. The aim of the current study was ...
Doerschner Katja - - 2011
Many critical perceptual judgments, from telling whether fruit is ripe to determining whether the ground is slippery, involve estimating the material properties of surfaces. Very little is known about how the brain recognizes materials, even though the problem is likely as important for survival as navigating or recognizing objects. Though ...
Bertrand Josie-Anne JA Department of Psychology, Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, C.P. 6128 Succ Centre-ville, Montréal, QC H3C 3J7, - - 2012
How the brain processes visual stimuli has been extensively studied using scalp surface electrodes and magnetic resonance imaging. Using these and other methods, complex gratings have been shown to activate the ventral visual stream, whereas moving stimuli preferentially activate the dorsal stream. In the current study, a first experiment assessed ...
Tomita Hidehito - - 2011
We examined the effects of anticipation certainty concerning which voluntary movement is required in response to a stimulus while standing on preparatory brain activity and anticipatory postural adjustments (APAs). Ten right-handed adults abducted their left or right arm rapidly in response to a visual imperative stimulus, based on the type ...
Johnson Curtis L - - 2011
In magnetic resonance elastography (MRE), shear waves at a certain frequency are encoded through bipolar gradients that switch polarity at a controlled encoding frequency and are offset in time to capture wave propagation using a controlled sampling frequency. In brain MRE, there is a possibility that the mechanical actuation frequency ...
Timmermann Lars - - 2011
A number of studies have identified pathological neural oscillations in Parkinson's disease and it is widely agreed that these excessive synchronizations are linked to the motor symptoms of Parkinson's disease (PD). However, it is still under debate if there exists a single frequency having a critical negative influence on PD ...
Squeri Valentina - - 2011
Introduction: Humans routinely use both of their hands to gather information about shape and texture of objects. Yet, the mechanisms of how the brain combines haptic information from the two hands to achieve a unified percept are unclear. This study systematically measured the haptic precision of humans exploring a virtual ...
Gross Michael - - 2011
Optogenetics - a new methodology that involves expression of light-responsive proteins in specific groups of neurons, which can then be activated with light - has only been around for six years, but some researchers are already using it to target big psychiatric questions. Michael Gross reports.
Wutte Magdalena G - - 2011
While moving through the world, humans as well as animals can make use of motion cues during both active and passive whole-body motion to track their own position in space. However, the functional neuroanatomy of self-motion processing remains poorly understood. In the present study we aimed to characterize brain networks ...
Jiruska Premysl - - 2011
Pathological high-frequency electrographic activity (pHFA, >80Hz) represents one of the major discoveries in epilepsy research over the past few decades. In this review we focus on the high-frequency activity recorded in vivo in chronic models of epilepsy. The presence of HFA particularly of fast ripples (250-600Hz)reflects epileptogenic reorganization of brain ...
Forgaard Christopher J CJ School of Kinesiology, University of British Columbia, War Memorial Gymnasium 210-6081 University Boulevard, Vancouver, BC, V6T 1Z1, - - 2011
In a choice reaction time (RT) paradigm, providing partial advance information (a precue) about the upcoming response has been shown to decrease RT, presumably due to preprogramming of the precued parameters. When advance information about a particular aspect of a movement is provided (precued), several different strategies might be used ...
Hughes Adam M - - 2011
Neuronal population oscillations at a variety of frequencies can be readily seen in electroencephalographic (EEG) as well as local field potential recordings in many different species. Although these brain rhythms have been studied for many years, the methods for identifying discrete oscillatory epochs are still widely variable across studies. The ...
Kirenskaya Anna V - - 2011
Abstract EEG spectral power and coherence were analyzed under waking baseline condition in 19 high (HH) and 12 low (LH) hypnotizable subjects. In HH subjects, the theta1 and theta2 spectral power was higher than in LH. The major new finding of this study is that coherence between distributed brain regions ...
Amzica Florin - - 2011
This paper describes the various electroencephalographic (EEG) patterns expressed by the comatose brain, starting with the sleep-like oscillations associated with light coma. Deeper coma generally displays a burst-suppression pattern characterized by alternating episodes of isoelectric (flat) EEG and bursting slow waves. The latter are the result of cortical hyperexcitability, as ...
Kaiser Martha D - - 2011
Typical adult observers demonstrate enhanced behavioral sensitivity to human movement compared to animal movement. Yet, the neural underpinnings of this effect are unknown. We examined the tuning of brain mechanisms for the perception of biological motion to the social relevance of this category of motion by comparing neural response to ...
Müller Markus F - - 2011
SUMMARY: To quantify the evolution of genuine zero-lag cross-correlations of focal onset seizures, we apply a recently introduced multivariate measure to broad band and to narrow-band EEG data. For frequency components below 12.5 Hz, the strength of genuine cross-correlations decreases significantly during the seizure and the immediate postseizure period, while ...
Aznar-Casanova Antonio A Institute for Brain, Cognition and Behavior (IR3C), Barcelona, - - 2011
In a three-dimensional (3-D) environment, sensory information is projected on a 2-D retina with the consequence that the visual system needs space information for accurately reconstructing the visual world. However, the 3-D environment is not accurately represented in the brain; in particular, the perception of distances in depth is imprecise. ...
Cross Emily S - - 2012
As humans, we gather a wide range of information about other people from watching them move. A network of parietal, premotor, and occipitotemporal regions within the human brain, termed the action observation network (AON), has been implicated in understanding others' actions by means of an automatic matching process that links ...
Dammers Jürgen - - 2011
Polarized light imaging (PLI) enables the visualization of fiber tracts with high spatial resolution in microtome sections of postmortem brains. Vectors of the fiber orientation defined by inclination and direction angles can directly be derived from the optical signals employed by PLI analysis. The polarization state of light propagating through ...
Mobbs Dean - - 2011
Approximately 3% of Americans declare to have had a near-death experience. These experiences classically involve the feeling that one's soul has left the body, approaches a bright light and goes to another reality, where love and bliss are all encompassing. Contrary to popular belief, research suggests that there is nothing ...
Sánchez-Nàcher Noemí - - 2011
Previous evidence suggests that the judged predictive strength of one cue may be influenced by the predictive strengths of other pretrained cues (prediction errors). In the present study, we examined affective ratings and event-related brain responses from 18 healthy participants during an aversive conditioning task in which affective values of ...
Shultz Sarah - - 2012
The conditions under which we identify entities as animate agents and the neural mechanisms supporting this ability are central questions in social neuroscience. Prior studies have focused upon 2 perceptual cues for signaling animacy: 1) surface features representing body forms such as faces, torsos, and limbs and 2) motion cues ...
Chen S-K - - 2011
Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin and regulate a wide array of light-dependent physiological processes. Genetic ablation of ipRGCs eliminates circadian photoentrainment and severely disrupts the pupillary light reflex (PLR). Here we show that ipRGCs consist of distinct subpopulations that differentially express the Brn3b transcription factor, ...
Baker Kenneth B - - 2011
Deep brain stimulation (DBS) involves the delivery of continuous, fixed-frequency electrical pulses to specific brain regions; however the reliance of therapeutic benefit on the fixed-frequency nature of the stimulation pattern is currently unknown. To address this, we investigated the effect of changes in the pattern and frequency of DBS in ...
Helfrich-Förster Charlotte - - 2011
Insects display an impressive variety of daily rhythms, which are most evident in their behaviour. Circadian timekeeping systems that generate these daily rhythms of physiology and behaviour all involve three interacting elements: the timekeeper itself (i.e. the clock), inputs to the clock through which it entrains and otherwise responds to ...
Foldes S T - - 2011
Paralyzed individuals can control the movement of an assistive device using changes in electroencephalographic (EEG) power resulting from attempted movements. Simultaneous, proportional control of two-dimensional (2D) device movements can be achieved with the concurrent modulation of brain activity that is associated with the attempted movement and rest of two independent ...
Rivlin-Etzion Michal - - 2011
On-Off direction-selective retinal ganglion cells (DSGCs) encode the axis of visual motion. They respond strongly to an object moving in a preferred direction and weakly to an object moving in the opposite, "null," direction. Historically, On-Off DSGCs were classified into four subtypes according to their directional preference (anterior, posterior, superior, ...
Sadeghi Navid G - - 2011
How does the brain represent the passage of time at the subsecond scale? Although different conceptual models for time perception have been proposed, its neurophysiological basis remains unknown. We took advantage of a visual duration illusion produced by stimulus novelty to link changes in cortical activity in monkeys with distortions ...
Vandewalle Gilles - - 2011
Light is a powerful modulator of cognition through its long-term effects on circadian rhythmicity and direct effects on brain function as identified by neuroimaging. How the direct impact of light on brain function varies with wavelength of light, circadian phase, and sleep homeostasis, and how this differs between individuals, is ...
Mysore Shreesh P - - 2011
Categorization is the process by which the brain segregates continuously variable stimuli into discrete groups. We report that patterns of neural population activity in the owl optic tectum (OT) categorize stimuli based on their relative strengths into "strongest" versus "other." The category boundary shifts adaptively to track changes in the ...
Hamada Toshiyuki - - 2011
The olfactory bulb (OB) of rodents has been suggested to possess a self-sustaining circadian oscillator which functions independent from the master circadian clock in the suprachiasmatic nucleus of the hypothalamus (SCN). However, neither histology nor physiology of this extra-SCN clock is studied yet. In the present study, we examined circadian ...
Mutha Pratik K - - 2011
The question addressed in this study is whether parietal brain circuits involved in adaptation to novel visuomotor conditions are lateralized. This information is critical for characterizing the neural mechanisms mediating adaptive behavior in humans, as well as for assessing the effects of unilateral brain damage on function. Moreover, previous research ...
Turrioni Ana Paula Silveira - - 2011
The influence of dentin permeability on transdentinal LED light propagation should be evaluated since this kind of phototherapy may further be clinically used to stimulate the metabolism of pulp cells, improving the healing of damaged pulps. This study evaluated the influence of the dentin permeability on the transdentinal LED light ...
Hirata Satoshi - - 2011
The sound of one's own name is one of the most salient auditory environmental stimuli. Several studies of human brain potentials have revealed some characteristic waveforms when we hear our own names. In a recent work, we investigated event-related potentials (ERPs) in a female chimpanzee and demonstrated that the ERP ...
Sifakakis Iosif - - 2011
The aim of this study was to assess the effect of bracket type on the labiopalatal forces and moments generated in the sagittal plane. Incognito™ lingual brackets (3M Unitek), STb™ lingual brackets (Light Lingual System; ORMCO), and conventional 0.018 inch slot brackets (Gemini; 3M Unitek) were bonded on three identical ...
Rios Daniela - - 2011
Objective: To evaluate whether the type of cola drink (regular or diet) could influence the wear of enamel subjected to erosion followed by brushing abrasion. Method and Materials: Ten volunteers wore intraoral devices that each had eight bovine enamel blocks divided into four groups: ER, erosion with regular cola; EAR, ...
1 2 3 4 5 6 7 8 9 10 >