Search Results
Results 1 - 50 of 680
1 2 3 4 5 6 7 8 9 10 >
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 - - 2012
RATIONALE: 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 ...
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 ...
Rodrigo Miguel - - 2011
In the last years, there has been an increasing interest in using Brain Computer Interfaces (BCI) within motor rehabilitation therapies that use robotic devices or functional electro stimulation to help or guide the efforts of the patient to move her body. A crucial step of these therapies is to provide ...
Muller Sandra Mara Torres - - 2011
This work presents a Brain-Computer Interface (BCI) based on Steady State Visual Evoked Potentials (SSVEP), using higher stimulus frequencies (>30 Hz). Using a statistical test and a decision tree, the real-time EEG registers of six volunteers are analyzed, with the classification result updated each second. The BCI developed does not ...
Higashi Hiroshi - - 2011
The spatial weights for electrodes called common spatial pattern (CSP) are known to be effective in EEG signal classification for motor imagery based brain computer interfaces (MI-BCI). To achieve accurate classification in CSP, the frequency filter should be properly designed. To this end, several methods for designing the filter have ...
Tanaka Hiroaki - - 2011
Anatomically distributed areas are dynamically linked to form functional networks for processing and integrating the different modalities of information in the human brain. A part of such networks is considered to be realized with synchronization of neuronal activities, which can generate correlated neural oscillation at the same and/or different frequency ...
Kim Do-Won - - 2011
Majority of the recently developed brain computer interface (BCI) systems have been using visual stimuli or visual feedbacks. However, the BCI paradigms based on visual perception might not be applicable to severe locked-in patients who have lost their ability to control their eye movement or even their vision. In the ...
Kang Eunji E - - 2011
The administration of the anesthetic agents is known to alter the electroencephalogram (EEG) signal significantly with the brain being their primary target. In this study, we analyzed the EEG recorded from six ASA I/II patients undergoing a 1-2 hour surgery. The EEG was collected before and during induction, maintenance and ...
Ng Kian B - - 2011
Steady-state visual evoked potential (SSVEP)-based Brain-Computer Interface (BCI) works on the basis that an attended stimulus shows an enhanced visual evoked response. By examining EEG power at the frequency of the dominant evoked response, we are able to determine which stimulus the subject is attending. However, due to the limited ...
Agashe Harshavardhan A - - 2011
With continued research on brain machine interfaces (BMIs), it is now possible to control prosthetic arm position in space to a high degree of accuracy. However, a reliable decoder to infer the dexterous movements of fingers from brain activity during a natural grasping motion is still to be demonstrated. Here, ...
Suminski Aaron J - - 2011
Although most brain-machine interface (BMI) studies have focused on decoding kinematic parameters of motion, it is known that motor cortical activity also correlates with kinetic signals, including hand force and joint torque. In this experiment, a monkey used a cortically-controlled BMI to move a visual cursor and hit a sequence ...
Porbadnigk Anne K - - 2011
Lighting in modern-day devices is often discrete. The sharp onsets and offsets of light are known to induce a steady-state visually evoked potential (SSVEP) in the electroencephalogram (EEG) at low frequencies. However, it is not well-known how the brain processes visual flicker at the threshold of conscious perception and beyond. ...
Cotic Marija - - 2011
We have used two algorithms, wavelet phase coherence (WPC) and modulation index (MI) analysis to study frequency interactions in the human epileptic brain. Quantitative analyses were performed on intracranial electroencephalographic (iEEG) segments from three patients with neocortical epilepsy. Interelectrode coherence was measured using WPC and intraelectrode frequency interactions were analyzed ...
Muto Yasuyuki - - 2011
We investigated the possibility of creating a temporal representation of brain activity from fNIRS signals. In an experiment, subjects performed isometric arm movements in four directions, and fNIRS signals were measured over the primary motor area in the left hemisphere of their brain. We estimated the direction of the arm ...
Song Xiaomu - - 2011
Functional magnetic resonance imaging (fMRI) techniques enable noninvasive studies of brain functional activity under task and resting states. However, the analysis of brain activity could be significantly affected by the cardiac- and respiration-induced physiological noise in fMRI data. In most multi-slice fMRI experiments, the temporal sampling rates are not high ...
Melia Umberto S P - - 2011
An efficient way to investigate the neural basis of nociceptive responses is the event-related brain potentials (ERPs). One component belonging to this family of ERPs is the mismatch negativity (MMN). It reflects pre-attentive detection of changes in the incoming stimulus by comparing the new stimulus with sensory memory traces. In ...
Liu Jiaen - - 2011
Being noninvasive, low-risk and inexpensive, EEG is a promising methodology in the application of human Brain Computer Interface (BCI) to help those with motor dysfunctions. Here we employed a center-out task paradigm to study the decoding of hand velocity in the EEG recording. We tested the hypothesis using a linear ...
Rubehn Birthe - - 2011
In this work, we describe the fabrication of a polymer-based shaft electrode which can conduct light as well as fluids to a target brain region and record electrical neural signals from the same tissue volume simultaneously. This multifunctional neural probe is intended to facilitate optogenetic in vivo experiments.
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 ...
1 2 3 4 5 6 7 8 9 10 >