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Kim Soyeon S Department of Applied Psychology & Human Development OISE, University of Toronto, Toronto, - - 2014
Individuals with attention-deficit/hyperactivity disorder (ADHD) are reported to manifest visual problems (including ophthalmological and color perception, particularly for blue-yellow stimuli), but findings are inconsistent. Accordingly, this study investigated visual function and color perception in adolescents with ADHD using color Visual Evoked Potentials (cVEP), which provides an objective measure of color ...
Noguchi Yasuki Y Department of Psychology, Graduate School of Humanities, Kobe University, 1-1 Rokkodai-cho, Nada, Kobe, 657-8501, Japan, - - 2014
Discriminating a direction of frequency change is an important ability of the human auditory system, although temporal dynamics of neural activity underlying this discrimination remains unclear. In the present study, we recorded auditory-evoked potentials when human subjects explicitly judged a direction of a relative frequency change between two successive tones. ...
Papesh Melissa A MA National Center for Rehabilitative Auditory Research, Portland VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, OR 97207, USA. Electronic address: - - 2014
To use cortical auditory evoked potentials (CAEPs) to understand neural encoding in background noise and the conditions under which noise enhances CAEP responses. CAEPs from 16 normal-hearing listeners were recorded using the speech syllable/ba/presented in quiet and speech-shaped noise at signal-to-noise ratios of 10 and 30dB. The syllable was presented ...
Scheerer Nichole E NE Psychology Department and Laurier Centre for Cognitive Neuroscience, Wilfrid Laurier University, 75 University Avenue West, Waterloo, ON, N2L 3C5, - - 2014
Speech production requires the combined effort of a feedback control system driven by sensory feedback, and a feedforward control system driven by internal models. However, the factors that dictate the relative weighting of these feedback and feedforward control systems are unclear. In this event-related potential (ERP) study, participants produced vocalisations ...
Fenton M Brock - - 2012
Duty cycle describes the relative 'on time' of a periodic signal. In bats, we argue that high duty cycle (HDC) echolocation was selected for and evolved from low duty cycle (LDC) echolocation because increasing call duty cycle enhanced the ability of echolocating bats to detect, lock onto and track fluttering ...
Zanotti-Fregonara Paolo - - 2012
Image-derived input function (IDIF) from carotid arteries is an elegant alternative to full arterial blood sampling for brain PET studies. However, a recent study using blood-free IDIFs found that this method is particularly vulnerable to patient motion. The present study used both simulated and clinical [11C](R)-rolipram data to assess the ...
Shestopalova L B - - 2012
The aim of the present study is to test whether mismatch negativity (MMN) response can be elicited by changes in auditory motion dynamics. The discrimination of auditory motion patterns was investigated using psychophysical and electrophysiological methods in the same group of subjects. Auditory event-related potentials (ERP) were recorded for stationary ...
Sanders Lia Lira Olivier - - 2012
Impaired perceptual inference has been suggested to be at the core of positive symptoms in schizophrenia. Apparent motion (AM) is a visual illusion in which perceptual inference gives rise to the experience of a single object moving back and forth when two spatially separated objects are flashed in alternation. Here, ...
Wu Haiyan - - 2012
The mechanism for motion detection in a fly's vision system, known as the Reichardt correlator, suffers from a main shortcoming as a velocity estimator: low accuracy. To enable accurate velocity estimation, responses of the Reichardt correlator to image sequences are analyzed in this paper. An elaborated model with additional preprocessing ...
Ibsen Stuart D - - 2012
A two-dimensional array of 16 hydrophones was created to map the spatial distribution of different frequencies within the echolocation beam of a Tursiops truncatus and a Pseudorca crassidens. It was previously shown that both the Tursiops and Pseudorca only paid attention to frequencies between 29 and 42 kHz while echolocating. ...
White Peter A - - 2012
Several tendencies found in explicit judgments about object motion have been interpreted as evidence that people possess a naive theory of impetus. The theory states that objects that are caused to move by other objects acquire force that determines the kind of motion exhibited by the object, and that this ...
Linnenschmidt Meike - - 2012
Some odontocetes and bats vary both click intensity and receiver sensitivity during echolocation, depending on target range. It is not known how this so-called automatic gain control is regulated by the animal. The source level of consecutive echolocation clicks from a harbour porpoise was measured with a hydrophone array while ...
Calabro F J FJ Brain and Vision Research Laboratory, Department of Biomedical Engineering, Boston University, Boston, MA, - - 2012
The task of parceling perceived visual motion into self- and object motion components is critical to safe and accurate visually guided navigation. In this paper, we used functional magnetic resonance imaging to determine the cortical areas functionally active in this task and the pattern connectivity among them to investigate the ...
Aaen-Stockdale Craig - - 2012
The intention of this series of experiments was to determine the extent to which the pathways sensitive to first-order and second-order motion are independent of one another at, and above, the level of global motion integration. We used translational, radial and rotational motion stimuli containing luminance-modulated dots, contrast-modulated dots, or ...
Hartmann Matthias - - 2012
We investigated the role of horizontal body motion on the processing of numbers. We hypothesized that leftward self-motion leads to shifts in spatial attention and therefore facilitates the processing of small numbers, and vice versa, we expected that rightward self-motion facilitates the processing of large numbers. Participants were displaced by ...
Mantani Shigeki - - 2012
Echolocation sounds of Rhinolophus ferrumequinum nippon as they approached a fluttering moth (Goniocraspidum pryeri) were investigated using an on-board telemetry microphone (Telemike). In 40 % of the successful moth-capture flights, the moth exhibited distinctive evasive flight behavior, but the bat pursued the moth by following its flight path. When the distance ...
Martini X - - 2012
Larvae of aphidophagous ladybirds leave a cue in their tracks that deters oviposition. The influence of relatedness on this behaviour is for the first time explored in this paper. Two-spot ladybird females (Adalia bipunctata L.) under different conditions (young and naive, young and experienced, and old and naive) were exposed ...
Villeneuve M Y - - 2012
Plaid stimuli are often used to investigate the mechanisms involved in the integration and segregation of motion information. Considering the perceptual importance of such mechanisms, only a very limited number of visual brain areas have been found to be specifically involved in motion integration. These are the human (h)MT+ complex, ...
Wang Jian - - 2012
Fundamental frequency difference limens (F0DLs) were measured for a target harmonic complex tone with nominal fundamental frequency (F0) of 200 Hz, in the presence and absence of a harmonic masker with overlapping spectrum. The F0 of the masker was 0, ±3, or ±6 semitones relative to 200 Hz. The stimuli were bandpass ...
Mahmudi Mentar - - 2012
We propose feature-based motion graphs for realistic locomotion synthesis among obstacles. Among several advantages, feature-based motion graphs achieve improved results in search queries, eliminate the need of post-processing for foot skating removal, and reduce the computational requirements in comparison to traditional motion graphs. Our contributions are threefold. First, we show ...
Quesada Luis - - 2012
Motion tracking is a critical task in many computer vision applications. Existing motion tracking techniques require either a great amount of knowledge on the target object or specific hardware. These requirements discourage the wide spread of commercial applications based on motion tracking. In this paper, we present a novel three ...
McCullough Stephen - - 2012
Previous research indicates that motion-sensitive brain regions are engaged when comprehending motion semantics expressed by words or sentences. Using fMRI, we investigated whether such neural modulation can occur when the linguistic signal itself is visually dynamic and motion semantics is expressed by movements of the hands. Deaf and hearing users ...
Dunderdale Gary James - - 2012
In this paper we show that processes such as Brownian motion, convection, sedimentation and bacterial contamination can cause small particles to move through liquids in a fashion which may be mistaken as nanopropulsion. It is shown that particle tracking and subsequent statistical analysis is essential to ascertain if small particles ...
Webster D R - - 2012
We designed and implemented a control algorithm for sensor-mediated chemical plume tracking in a turbulent flow environment. In our design, we focused on development of a signal processing strategy capable of replicating behavioral responses of actively tracking blue crabs (Callinectes sapidus) to chemical stimuli. The control algorithm is evaluated in ...
Zabala Francisco - - 2012
An important role of visual systems is to detect nearby predators, prey, and potential mates [1], which may be distinguished in part by their motion. When an animal is at rest, an object moving in any direction may easily be detected by motion-sensitive visual circuits [2, 3]. During locomotion, however, this ...
Falzon O - - 2012
Brain-computer interface (BCI) systems based on steady-state visual evoked potentials (SSVEPs) have gained considerable popularity because of the robustness and high information transfer rate these can provide. Typical SSVEP setups make use of visual targets flashing at different frequencies, where a users choice is determined from the SSVEPs elicited by ...
Galante Amanda - - 2012
Synechocystis sp., a common unicellular freshwater cyanobacterium, has been used as a model organism to study phototaxis, an ability to move in the direction of a light source. This microorganism displays a number of additional characteristics such as delayed motion, surface dependence, and a quasi-random motion, where cells move in ...
Carroll T L - - 2012
Reflecting signals off of targets is a method widely used to locate objects, but the reflected signal also contains information that can be used to identify the object. In radar or sonar, the signal amplitudes used are small enough that only linear effects are present, so we can consider the ...
Fattori G - - 2012
Purpose: To integrate and test an optical tracking platform for motion detection in scanned ion beam tracking for organ motion compensation. Methods: An infra-red optical tracking system (IR-OTS) has been integrated into the treatment control system to test beam tracking for organ motion compensation in the framework of a nearly ...
Schmitt D - - 2012
Purpose: Evaluation of different calculation methods for dose modification due to intrafraction prostate motion using film measurements as ground truth. Methods: We acquired intrafraction motion data with the Calypso tumor tracking system by Varian Medical Systems Inc for 4 prostate IMRT patients treated with 35 fractions each. These motion data ...
Audenaert Emmanuel - - 2012
Recent epidemiological studies have demonstrated that radiographic features specific to femoroacetabular impingement appear far more frequently in healthy and asymptomatic cohorts than previously anticipated. It remains unclear how incidental findings should be interpreted clinically. In addition, several authors have suggested that a decreased range of motion is part of the ...
Appleby-Thomas G J - - 2012
Plate-impact experiments have been used to interrogate the influence of gauge alignment on the shock response of wire-element lateral manganin stress gauges in PMMA and aluminium targets. Embedded gauges were progressively rotated relative to the target impact face. Peak stress and lateral gauge rise-times were found be proportional (negatively and ...
Holland Charles W - - 2012
Clutter, or discrete target-like returns, is the most significant problem in the employment of active sonar. It is well understood that discrete objects, which are of the same spatial scale as the target and which possess a significant impedance contrast to the surrounding ocean, can lead to clutter. Here a ...
Lim S - - 2012
Purpose: The accuracy of the tracking system is critical for the result of four-dimensional radiation therapy. The objective of this study is to propose the method of verifying the accuracy of respiratory tracking system. Methods: The scintillation screen and the light marker between the transparent acrylic plates were designed to ...
Gautier Q - - 2012
Purpose: During the treatment, a patient is continuously monitored by video cameras. The therapists are supposedly to watch the monitors and interrupt the treatment if any significant patient motion is spotted. Unfortunately, patient motion can easily be overlooked with this manual approach, especially when there are many other monitors in ...
Buzurovic I - - 2012
Purpose: The purpose of this study was to present a novel method for real- time tumor tracking using a commercially available robotic treatment couch, and to evaluate tumor tracking accuracy. Methods: Commercially available robotic couches are capable of positioning patients with high level of accuracy; however, currently there is no ...
Liu W - - 2012
Purpose: To reconstruct the motion manifold defined on anatomical interfaces from real-time MR imaging. Methods∷We have developed a novel method to construct the evolving motion manifold in real-time by preserving the point correspondence when a level set function is updated to track moving anatomical interfaces. The key to our development ...
van Breugel Floris - - 2012
Landing behavior is one of the most critical, yet least studied, aspects of insect flight. In order to land safely, an insect must recognize a visual feature, navigate towards it, decelerate, and extend its legs in preparation for touchdown. Although previous studies have focused on the visual stimuli that trigger ...
Ahmad M - - 2012
Purpose: Undersampling artifacts are a major problem in four-dimensional cone-beam computed tomography (4D-CBCT) and may compromise evaluation of target motion. The role of the target characteristics in scan parameter selection has not been previously investigated. In this work, we evaluated 4D-CBCT performance by assessing the accuracy of target motion measurements ...
Li S - - 2012
Purpose: To introduce video surface imaging guidance in synchronization with 4D cone-beam CT (CBCT) scans, and in combination with respiration- gated or target-tracked dose delivery to treat mobile tumors, without collaterally damaging nearby critical structures. Methods: The approach uses the concept that the integral of balanced forces over the moving ...
Yue Y - - 2012
Purpose: To track prostate motion during clinical arc radiotherapy using a novel statistical motion tracking algorithm in both phantom and patient systems. Methods: For the phantom study, a dynamic phantom with a custom tumor model and radiopaque fiducials was used. For the patient study, the clinical data from two prostate ...
Cheung K - - 2012
Purpose: To develop a dynamic dosimetry phantom suitable for commissioning and QA of gated RapidArc radiotherapy of moving targets. Methods: A high precision dynamic dosimetry phantom was developed for commissioning and dosimetric verification of gated RapidArc radiotherapy treatments. The phantom consisted of two main parts (a) a high precision 3-D ...
Lange-Malecki Bettina - - 2012
Visual motion perception is essential for appropriate behavior in a dynamic visual world. It is influenced by voluntary attention towards or away from moving objects as well as by the capture of automatic attention by salient stimuli. Both kinds of attention play a major role in the Eriksen Flanker Task ...
Park Justin C - - 2012
Purpose: Purpose of this study was to investigate the motion characteristics of liver during SBRT, based on fiducial markers tracked with X-ray projections of CBCT scans, taken immediately prior to each treatment. Methods: Purpose of this study was to investigate the motion characteristics of liver during SBRT, based on fiducial ...
Ehara I - - 2012
Purpose: In intensity modulated radiation therapy (IMRT) and/or volumetric modulated arc therapy (VMAT), it is important to ensure the accuracy of multi-leaf collimator (MLC) motion during delivery. However, the commercially available software can evaluate only summary of MLC motion during delivery as the error's root-mean-square (RMS). The purposeof this study ...
Koshino Kazuhiro - - 2012
Patient movement has been considered an important source of errors in cardiac PET. This study was aimed at evaluating the effects of such movement on myocardial blood flow (MBF) and perfusable tissue fraction (PTF) measurements in intravenous ¹⁵O-water PET. Nineteen ¹⁵O-water scans were performed on ten healthy volunteers and three ...
Huk Alexander C - - 2012
This article begins by reviewing recent work on 3D motion processing in the primate visual system. Some of these results suggest that 3D motion signals may be processed in the same circuitry already known to compute 2D motion signals. Such "multiplexing" has implications for the study of visual cortical circuits ...
Rañó Iñaki - - 2012
Motion camouflage is a stealth behaviour observed both in hover-flies and in dragonflies. Existing controllers for mimicking motion camouflage generate this behaviour on an empirical basis or without considering the kinematic motion restrictions present in animal trajectories. This study summarises our formal contributions to solve the generation of motion camouflage ...
Spering Miriam - - 2012
Feature-based attention enhances visual processing and improves perception, even for visual features that we are not aware of. Does feature-based attention also modulate motor behavior in response to visual information that does or does not reach awareness? Here we compare the effect of feature-based attention on motion perception and smooth-pursuit ...
Garcia Javier O - - 2012
The brain systems that support motion perception are some of the most studied in the primate visual system, with apparent specialization in the middle temporal area (hMT+in humans, MT or V5 in monkeys). Even with this specialization, it is safe to assume that the hMT+interacts with other brain systems as ...
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