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Results 451 - 500 of 1344
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Chung Sooyoung - - 2011
The mammalian circadian timing system is organized into hierarchical structures with a central clock in the suprachiasmatic nucleus (SCN) and subsidiary peripheral oscillators. After the discovery of the local clockwork in peripheral organs and tissues, which have a molecular makeup similar to the central pacemaker SCN, uncovering the roles of ...
Yakushin Sergei B SB Department of Neurology, Mount Sinai School of Medicine, New York, NY 10029, USA. - - 2011
We investigated spatial responses of the aVOR to small and large accelerations in six canal-plugged and lateral canal nerve-sectioned monkeys. The aim was to determine whether there was spatial adaptation after partial and complete loss of all inputs in a canal plane. Impulses of torques generated head thrusts of ≈ ...
Christensen-Dalsgaard Jakob - - 2011
Lizards have highly directional ears, owing to strong acoustical coupling of the eardrums and almost perfect sound transmission from the contralateral ear. To investigate the neural processing of this remarkable tympanic directionality, we combined biophysical measurements of eardrum motion in the Tokay gecko with neurophysiological recordings from the auditory nerve. ...
Lee Byung Woo - - 2011
The purpose of this study was to use digital videofluoroscopy to identify motion patterns of the lumbar spine during coronal movement in asymptomatic (normal) subjects and patients with herniated nucleus pulposus (HNP). Videofluoroscopic lumbar coronal motion was recorded in 18 asymptomatic volunteers and 9 patients with HNP. Measurements were made ...
Frasnelli J - - 2011
When an odorant is presented to one side of the nose and air to the other, the ability to localize which side received the odorant depends upon trigeminal nerve stimulation. It has been shown that performance on this lateralization task increases as stimulus concentration increases. In this study, we determined ...
Jennings Skyler G SG Department of Speech, Language, and Hearing Sciences, Purdue University, 500 Oval Drive, West Lafayette, IN 47907, USA. - - 2011
Masked detection threshold for a short tone in noise improves as the tone's onset is delayed from the masker's onset. This improvement, known as "overshoot," is maximal at mid-masker levels and is reduced by temporary and permanent cochlear hearing loss. Computational modeling was used in the present study to evaluate ...
Versteegh Corstiaen P C - - 2011
In this study, we analyze the processing of low-frequency sounds in the cochlear apex through responses of auditory nerve fibers (ANFs) that innervate the apex. Single tones and irregularly spaced tone complexes were used to evoke ANF responses in Mongolian gerbil. The spike arrival times were analyzed in terms of ...
Rijkhorst Erik-Jan - - 2011
To quantify the effects of respiratory motion on high-intensity focused ultrasound heating of liver tissue by comparing the simulated ablation using a conventional respiratory gating versus a MR-model-based motion compensation approach. To measure liver motion, dynamic free-breathing abdominal MR scans were acquired for five volunteers. Deformable registration was used to ...
Czuba Thaddeus B TB Center for Perceptual Systems, Department of Psychology & Section of Neurobiology, The University of Texas at Austin, Austin, TX 78712-0189, USA. - - 2011
Motion aftereffects are historically considered evidence for neuronal populations tuned to specific directions of motion. Despite a wealth of motion aftereffect studies investigating 2D (frontoparallel) motion mechanisms, there is a remarkable dearth of psychophysical evidence for neuronal populations selective for the direction of motion through depth (i.e., tuned to 3D ...
Kim Kyung K Research Institute, National Rehabilitation Center, Korea. - - 2011
Analyzing activities of daily living (ADL) for the development of practical upper limb rehabilitation robots is challenging in stroke patients. Basic ADL tasks using an upper limb are defined based on clinical assessment tools. The motions of 8 healthy participants and 8 stroke patients were recorded during defined ADL tasks, ...
Li Guanglin G Key Laboratory of Health Informatics of Chinese Academy of Sciences, Shenzhen Institutes of Advanced Technology, CAS, Shenzhen, Guangdong 518055, China. - - 2011
Electromyography (EMG) signals are commonly recorded using the Ag/AgCl gel electrodes in myoelectric prosthetic control. While a gelled electrode may provide high-quality EMG recordings, it is inconvenient in clinical application of a myoelectric prosthesis. A novel type of signal sensors-textile electrodes should be ideal in control of myoelectric prostheses. However, ...
Terao Masahiko - - 2011
Motion perception is compromised at equiluminance. Because previous investigations have been primarily carried out under fixation conditions, it remains unknown whether and how equiluminant color motion comes into play in the velocity compensation for retinal image motion due to smooth pursuit eye movement. We measured the retinal image velocity required ...
Thomas Laura E - - 2011
Perhaps walking and chewing gum is effortless, but walking and tracking moving objects is not. Multiple object tracking is impaired by walking from one location to another, suggesting that updating location of the self puts demands on object tracking processes. Here, we quantified the cost of self-motion in terms of ...
Holstein Gay R GR Department of Neurology, Mount Sinai School of Medicine, New York, NY 10029, USA. - - 2011
The vestibular system senses the movement and position of the head in space and uses this information to stabilize vision, control posture, perceive head orientation and self-motion in three-dimensional space, and modulate autonomic and limbic activity in response to locomotion and changes in posture. Most vestibular signals are not consciously ...
Pei Y Y Graduate School of Engineering, Nagoya University Furo-cho, Chikusa-ku, Nagoya - - 2011
We introduce a method for lower-limb physical rehabilitation by means of a robot that applies preliminary defined forces to a patient's foot while moving it on a preliminary defined trajectory. We developed a special musculoskeletal model that takes into consideration the generated muscle forces of 27 musculotendon actuators and joint ...
Masuda Kohji K Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan. - - 2011
We have developed a support system using our ultrasound diagnosis robot, which is able to support manual handling of ultrasound probe in echography to alleviate fatigue of examiner. This system realizes a coordinated motion according to the motion of the probe, which is hold by the robot and is moved ...
Perez Ronen - - 2011
According to classic theories, auditory stimulation, whether air- or bone-conducted, has been thought to begin with sound-induced relative motion between the cochlear shell and the stapes footplate, producing a passive mechanical traveling wave along the basilar membrane. This study was designed to assess the effect of experimental mechanical manipulations of ...
Trojnacki Maciej T - - 2011
In this paper, the method of generating biped robot motion using recorded human gait is presented. The recorded data were modified taking into account the velocity available for robot drives. Data includes only selected joint angles, therefore the missing values were obtained considering the dynamic postural stability of the robot, ...
Scarfe Peter - - 2011
Early cortical responses to visual motion are inherently ambiguous as to underlying motion in the world. This ambiguity derives from the fact that directionally selective cells in early visual areas, such as V1, can predominantly signal only 1D motion orthogonal to image contours spanning their small, spatially localized, receptive fields. ...
Lu Yanyu - - 2011
A visual prosthesis provides usable visual information to the patient in the form of phosphenes, that is, punctate photic sensations seen after electrical stimulation. Stimulation via different electrodes results in phosphenes in different positions within the visual field. Simulation studies can provide data on the possible limitations of prosthetic stimulation. ...
Zhao Wei - - 2011
The medial olivocochlear (MOC) pathway modulates basilar membrane motion and auditory nerve activity on both a fast (10-100 ms) and a slow (10-100 s) time scale in guinea pigs. The slow MOC modulation of cochlear activity is postulated to aide in protection against acoustic trauma. However in humans, the existence ...
Jean Frédéric F Department of Electrical and Computer Engineering, Laval University, Québec, QC, Canada. - - 2011
This paper describes a novel algorithm for tracking the motion of the urethra from trans-perineal ultrasound. Our work is based on the structure-from-motion paradigm and therefore handles well structures with ill-defined and partially missing boundaries. The proposed approach is particularly well-suited for video sequences of low resolution and variable levels ...
Beran Michael J - - 2011
Two monkey species (Macaca mulatta and Cebus apella) and human children and adults judged the numerousness of two subsets of moving stimuli on a computer screen. Two sets of colored dots that varied in number and size were intermixed in an array in which all dots moved in random directions ...
Kaunitz Lisandro - - 2011
The relationship between attention and awareness and the processing of visual information outside of attention and awareness remain controversial issues. We employed the motion aftereffect (MAE) illusion and continuous flash suppression (CFS) to study the behavioral effects of unseen and unattended visual motion. The main finding was that either withdrawal ...
Hergovich Andreas - - 2011
Following Gustav Kuhn's inspiring technique of using magicians' acts as a source of insight into cognitive sciences, we used the 'paddle move' for testing the psychophysics of combined movement trajectories. The paddle move is a standard technique in magic consisting of a combined rotating and tilting movement. Careful control of ...
Kirst Malte M Institute for Information Processing Technology, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany. - - 2011
Dealing with motion artifacts in long-term ECG recordings is a big issue. The frequency spectrum of motion artifacts is similar to the frequencies of the QRS complex--the wanted signal in the ECG. The deletion of motion artifacts often leads to a deformation of QRS complexes, too. These risks can be ...
Nagata Kentaro K Kanagawa Rehabilitation Institute, Japan. - - 2011
To improve degree of freedom (DOF) of system control using surface electromyogram (SEMG), we made a basic study of the estimation of user's intended motion including combined motion which is performed by more than one basic motion simultaneously. Our developed system requested to obtain three SEMG characteristics of basic motion ...
Asundi Krishna - - 2011
Objective: Compare wrist kinematics and typing force during computer work across two workstations, one configured according to recommended guidelines with the keyboard support surface flat and near resting elbow height, the other according to users' actual setup and preference, with an elevated, and positively tilted support surface. Participants: Twenty participants ...
Bonato Frederick - - 2011
The nauseogenic properties of a patterned rug that reputedly caused motion-sickness-like symptoms in those who viewed it was the topic of this study. Naive observers viewed a 1:1 scale image of the black-and-white patterned rug and a homogeneous gray region of equivalent luminance in a counterbalanced within-subjects design. After 5 ...
Sancisi Nicola N DIEM - Department of Mechanical Engineering, University of Bologna. - - 2011
Orthoses and exoskeletons need devices that can replicate the natural spatial motion of human joints. These devices should be simple and should have a high accuracy, in order not to constrain and load the joints unnaturally. In this study, strip-driven devices are proposed to guide the spatial joint motion. Classic ...
Bhowmik Ujjal Kumar UK Department of Electrical and Computer Engineering The University of Alabama in Huntsville Huntsville, AL-35899, USA. - - 2011
Head motion during brain CT studies can degrade the reconstructed image by introducing distortion and loss of resolution, thereby contributing to misdiagnosis of diseases. In this paper, we have proposed a correlation coefficient and Least Squares Support Vector Machines (LS-SVM) based approach to detect and mitigate motion artifacts in FDK ...
Chen Lihan - - 2011
Apparent motion can occur within a particular modality or between modalities, in which a visual or tactile stimulus at one location is perceived as moving towards the location of the subsequent tactile or visual stimulus. Intramodal apparent motion has been shown to be affected or 'captured' by information from another, ...
Low Daniel - - 2011
Recently developed 4D CT imaging technologies have shown that significant organ motion can occur within radiotherapy fields during treatment. Most often a result of respiration, this motion can cause dose delivery errors that are clinically significant when unmanaged, as demonstrated in many recent investigations. Motion during the regular breathing cycling ...
Takemura Hiromasa - - 2011
When two random-dot patterns moving in different directions are superimposed, motion appears coherent or transparent depending on the directional difference. In addition, when a pattern is surrounded by another pattern that is moving, the perceived motion of the central stimulus is biased away from the direction of the surrounding motion. ...
Tyler Sarah C - - 2011
Motion perception is important for visually segregating and identifying objects from their surroundings, but in some cases extracting motion cues can be taxing to the human attention system. We measured the strength of feature salience required for individuals to correctly judge three types of moving events: biological motion, coherent motion, ...
Nagai Takehiro - - 2011
Objects are critical functional units for many aspects of visual perception and recognition. Many psychophysical experiments support the concept of an "object file" consisting of characteristics attributed to a single object on the basis of successive views of it, but there has been little evidence that object identity influences apparent ...
Khuu Sieu K - - 2011
Visual saltation is the illusory mislocalization that occurs when multiple elements are rapidly presented to two peripheral locations; mislocalized elements appear to fill in the intermediate space. We investigated the influence of element orientation on the path of illusory saltatory motion. Experiment 1 showed that congruence in element orientation at ...
Or Charles C-F - - 2011
Humans are extremely sensitive to radial deformations of static circular contours (F. Wilkinson, H. R. Wilson, & C. Habak, 1998). Here, we investigate detection and identification of periodic motion trajectories defined by these radial frequency (RF) patterns over a range of radial frequencies of 2-5 cycles. We showed that the ...
Hafner Noah N Department of Electrical Engineering, University of Hawaii at Mānoa, Honolulu, Hawaii 96822, USA. - - 2011
Close-range underwater sensing of motion-based life signs can be performed with low power Doppler radar and ultrasound techniques. Corresponding noise and range performance trade-offs are examined here, with regard to choice of frequency and technology. The frequency range examined includes part of the UHF and microwave spectrum. Underwater detection of ...
van der Willigen Robert F - - 2011
While 3D experiences through binocular disparity sensitivity have acquired special status in the understanding of human stereo vision, much remains to be learned about how binocularity is put to use in animals. The owl provides an exceptional model to study stereo vision as it displays one of the highest degrees ...
Murphy Barbara A - - 2011
In contrast to studies showing gradual adaptation of melatonin (MT) rhythms to an advanced photoperiod in humans and rodents, we previously demonstrated that equine MT rhythms complete a 6-h light/dark (LD) phase advance on the first post-shift day. This suggested the possibility that melatonin secretion in the horse may be ...
Benoliel Rafael - - 2011
Aims: To assess the effects of four- and six-point acupuncture on facial sensory detection thresholds to thermal and electrical stimuli. Methods: Ten healthy volunteers underwent four-point acupuncture at ST6 and LI4 bilaterally for 15 minutes. A further 10 subjects underwent six-point acupuncture by adding needling at ST2 bilaterally. Sensory testing ...
von Hopffgarten Anna - - 2011
Successful locomotion through space requires precise estimation of the direction and distance travelled. Previous studies have shown that humans can use velocity information arising from visual, vestibular and somatosensory signals to reproduce passive linear displacements. In the present study we investigated whether also associated auditory velocity cues are used for ...
Lee Beom-Chan BC Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA. - - 2011
The Mobile Instrument for Motion Instruction and Correction (MIMIC) enables an expert (i.e., physical therapist) to map his/her movements to a trainee (i.e., patient) in a hands-free fashion. MIMIC comprises an Expert Module (EM) and a Trainee Module (TM); both modules include six-degree-of-freedom inertial measurement units, microcontrollers, and batteries. The ...
Gorzelniak Lukas - - 2011
For the assessment of physical activity, motion sensors have become increasingly important. To assure a high accuracy of the generated sensor data, the measurement error of these devices needs to be determined. Sensor variability has been assessed with various types of mechanical shakers. We conducted a small feasibility study to ...
Escobar Carolina - - 2011
The relevance of a synchronized temporal order for adaptation and homeostasis is discussed in this review. We present evidence suggesting that an altered temporal order between the biological clock and external temporal signals leads to disease. Evidence mainly based on a rodent model of "night work" using forced activity during ...
Bowns Linda - - 2011
Distortions of the local spatial-frequency power spectrum caused by motion blur may be used by the visual system to improve motion analysis (e.g., Barlow and Olshausen, 2004 Journal of Vision 4415-426). We tested this hypothesis by measuring the error of perceived motion direction of moving patterns in the presence of ...
Lorteije Jeannette A M - - 2011
The calyx of Held synapse is a giant synapse in the medial nucleus of the trapezoid body (MNTB) of the ventral brainstem, which is involved in sound localization. Although it has many release sites, it can show transmission failures and display an increase in synaptic delay during high-frequency signalling. Its ...
Lee Seunghoon S Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, CT 06510, - - 2010
Starburst amacrine cells (SACs) process complex visual signals in the retina using both acetylcholine (ACh) and gamma-aminobutyric acid (GABA), but the synaptic organization and function of ACh-GABA corelease remain unclear. Here, we show that SACs make cholinergic synapses onto On-Off direction-selective ganglion cells (DSGCs) from all directions but make GABAergic ...
Colletti Vittorio - - 2010
Background The rapid spread of devices generating electromagnetic fields (EMF) has raised concerns as to the possible effects of this technology on humans. The auditory system is the neural organ most frequently and directly exposed to electromagnetic activity owing to the daily use of mobile phones. In recent publications, a ...
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