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Occelli Valeria - - 2011
The last few years have seen a growing interest in the assessment of audiotactile interactions in information processing in peripersonal space. In particular, these studies have focused on investigating peri-head space and, more recently, on the functional differences that have been demonstrated between the space close to front and back ...
MacNeilage Paul R PR Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, Missouri 63110, - - 2010
Effective navigation and locomotion depend critically on an observer's ability to judge direction of linear self-motion, i.e., heading. The vestibular cue to heading is the direction of inertial acceleration that accompanies transient linear movements. This cue is transduced by the otolith organs. The otoliths also respond to gravitational acceleration, so ...
Guida Heraldo Lorena - - 2010
Noise-induced hearing loss has been studied for many years and today many experts also investigate the synergic action of chemical products, since they can be potentially ototoxic. to investigate the audiological findings in workers exposed to occupational noise and pesticide and to compare it to data from noise-exposed workers. Clinical ...
Mateo B - - 2010
This study demonstrates that appropriate measurement procedures can detect differences in head movement in a near reading task when using three different progressive addition lenses (PALs). The movements were measured using an anatomical reference system with a biomechanical rationale. This reference system was capable of representing rotations for comparing head ...
Kaplan David M - - 2010
Game et al. (2009) explored using rapid rotational fishing for increasing herbivore biomass. Their results depend crucially on the assumption that fishing effort that was in closures disappears, rather than shifting elsewhere. If effort shifts, rapid rotation has no effects, but previous age-structured analyses show benefits of longer period rotation ...
MacNeilage Paul R - - 2010
Gravitational signals arising from the otolith organs and vertical plane rotational signals arising from the semicircular canals interact extensively for accurate estimation of tilt and inertial acceleration. Here we used a classical signal detection paradigm to examine perceptual interactions between otolith and horizontal semicircular canal signals during simultaneous rotation and ...
Yakusheva Tatyana T Department of Neurobiology, Washington University School of Medicine, St. Louis, Missouri 63110, - - 2010
Lobules 10 and 9 in the caudal posterior vermis [also known as nodulus and uvula (NU)] are thought important for spatial orientation and balance. Here, we characterize complex spike (CS) and simple spike (SS) activity in response to three-dimensional vestibular stimulation. The strongest modulation was seen during translation (CS: 12.8 ...
Mallery Robert M RM Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, Saint Louis, MO 63110, - - 2010
Vestibular reflexes are critically important for stabilizing gaze and maintaining posture, but comparatively little is known about conscious perceptions of vestibular stimuli and how they may relate to balance function. We used psychophysical methods to determine the ability of normal subjects and a vestibular-deficient subject to discriminate among velocities of ...
Lee Seung-Han - - 2010
Benign paroxysmal positional vertigo (BPPV) is characterized by brief recurrent episodes of vertigo triggered by changes in head position. BPPV is the most common etiology of recurrent vertigo and is caused by abnormal stimulation of the cupula by free-floating otoliths (canalolithiasis) or otoliths that have adhered to the cupula (cupulolithiasis) ...
Gu Yong Y Department of Neurobiology, Washington University School of Medicine, St. Louis, MO 63110, - - 2010
Humans and monkeys use both vestibular and visual motion (optic flow) cues to discriminate their direction of self-motion during navigation. A striking property of heading perception from optic flow is that discrimination is most precise when subjects judge small variations in heading around straight ahead, whereas thresholds rise precipitously when ...
Thomas Biju B BB Doheny Retina Institute, Doheny Eye Institute, 1450 San Pablo St., Los Angeles, CA 90033, United States. - - 2010
Optokinetic testing is a non-invasive technique, widely used for visual functional evaluation in rodents. The modulatory influence of optokinetic stimulus parameters such as contrast level and grating speed on head-tracking response in normal and retinal degenerate (RD) mice (rd10) and rats (S334ter-line-3) was evaluated using a computer-based testing apparatus. In ...
Stecker G Christopher - - 2010
Listeners detected interaural differences of time (ITDs) or level (ILDs) carried by single 4000-Hz Gabor clicks (Gaussian-windowed tone bursts) and trains of 16 such clicks repeating at an interclick interval (ICI) of 2, 5, or 10 ms. In separate conditions, target interaural differences favored the right ear by a constant ...
Kashou Nasser H - - 2010
Modifying experimental conditions of optokinetic nystagmus (OKN) result in different outcomes and may not optimally translate into clinical testing. The purpose of this study was to assess the influence of subject instruction on the anatomical correlates of OKN. The instructions were to voluntarily look or stare at the same moving ...
Fushiki Hiroaki - - 2010
OBJECTIVE: We examined the emerging vertical component after cross-axis vestibulo-ocular reflex (VOR) adaptation. METHODS: For the adaptive conditioning, the whole body of a subject was rotated horizontally while a visual pattern was rotated vertically for 1h. RESULTS: During the conditioning period, the vertical component in response to the vertical visual ...
Chandrakumar Manokaraananthan - - 2010
To investigate whether static ocular counterroll (OCR) gain is reduced during viewing of an earth-fixed vs a head-fixed target. Twelve healthy individuals were recruited. The target consisted of a red fixation cross against a grid pattern at a viewing distance of 33 cm. The target was mounted on a wall ...
Kandel Benjamin M - - 2010
The semicircular canals measure head rotations, providing information critical for maintaining equilibrium. The canals of cetaceans (including whales, dolphins and porpoises) are extraordinarily small, making them unique exceptions to the allometric relationship shared by all other vertebrates between canal size and animal mass. Most modern cetaceans have shorter and less ...
Byun Jae Yong - - 2010
OBJECTIVES: By assessing unilateral utricular function at the acute and subacute stages, we sought to determine the ability of the subjective visual vertical (SVV) during eccentric rotation (dynamic SVV) in detecting latent abnormality of otolith dysfunction in unilateral vestibular neuritis. In addition, we compared the validity of the dynamic SVV ...
Sunny Megha - - 2010
In this work, we will examine the problem of detecting the angular motion of head in effort to build a head-tracking system to control sound. The head motion occurs in X, Y, and Z linear directions and three rotation angles, namely pitch, roll, and yaw. In the past, we had ...
Zhang Yundong - - 2010
We report the experimental observation of enhanced rotation sensing in a slow-light structure. We demonstrate that the differential of the phase difference, introduced by rotation, between the counterpropagating waves is proportional to the group index, and thus we can obtain large rotation sensitivity in the slow-light structure with high dispersion ...
Horan Sean A - - 2010
Thorax and pelvis motion during the golf swing have most frequently been described for male golfers at discrete points during the swing, such as top of backswing (TBS) and ball contact (BC). Less is known about the continual motion and coordination of the thorax and pelvis throughout the downswing for ...
Goumans Janine - - 2010
The three-dimensional vestibulo-ocular reflex (3D VOR) ideally generates compensatory ocular rotations not only with a magnitude equal and opposite to the head rotation but also about an axis that is collinear with the head rotation axis. Vestibulo-ocular responses only partially fulfill this ideal behavior. Because animal studies have shown that ...
Koo Ja-Won - - 2010
Thinning or dehiscence of the superior semicircular canal may occur on the middle cranial fossa floor or adjacent to the superior petrosal sinus (SPS). However, no symptomatic cases of superior canal dehiscence by SPS have been previously described. A 45-year-old woman presented with left-side pulsating tinnitus, autophony and disequilibrium. Examination ...
Snyder Janice J - - 2010
Past research indicates that observers rely strongly on flow-based and object-based motion information for determining egomotion or direction of heading. More recently, it has been shown that they also rely on displacement information that does not induce motion perception. As yet, little is known regarding the specific displacement cues that ...
Saeys Wim - - 2010
In this study the influence of head-on-body and starting roll position of laser bar and chair was investigated on the perception of, respectively, the visual and postural vertical. Sixty-one subjects, between 21 and 82 years, participated in this study. Results show that head-on-body and starting roll position of laser bar ...
Muelenz Cornelius - - 2010
Although observers know about the law of reflection, their intuitive understanding of spatial locations in mirrors is often erroneous. Hecht et al. (2005) proposed a two-stage mirror-rotation hypothesis to explain these misconceptions. The hypothesis involves an egocentric bias to the effect that observers behave as if the mirror surface were ...
Bhasin Shaaista - - 2010
Profiles may vary in expression with changes in the height of the profile's features, the mouth's angle at the profile contour, and head tilt. In three experiments, we varied these factors. Features low on the profile, with mouths at an obtuse angle to the profile line and head tilted 15 ...
Wachowski Martin Michael - - 2010
The biomechanical role of the zygapophysial joints was investigated for axial rotations of lumbar segments by recording the positions of the instantaneous helical axis (IHA) against the axial rotational angle and by relating these IHA-positions to anatomical landmarks. Cyclically varying pure axial moments were applied to 3 L1/L2, 7 L3/L4 ...
Jarchow T - - 2010
Subjective body position, as influenced by 21-day 6 degrees -head-down bed rest and intermittent supine centrifugation, was investigated in two experimental groups. Treatment subjects were exposed to a daily dose of 1-hour of horizontal centrifugation, whereas control subjects were also put on the centrifuge, but were not spun. During the ...
Zhang Lelin L University of California San Diego, La Jolla, CA 92093, - - 2010
Wireless physiological/neurological monitoring in virtual reality (VR) offers a unique opportunity for unobtrusively quantifying human responses to precisely controlled and readily modulated VR representations of health care environments. Here we present such a wireless, light-weight head-mounted system for measuring electrooculogram (EOG) and electroencephalogram (EEG) activity in human subjects interacting with ...
Sejdić Ervin - - 2010
Head motions can severely affect dual-axis cervical acceloremetry signals. A complete understanding of the effects of head motion is required before a robust accelerometry-based medical device can be developed. In this paper, we examine the spectral characteristics of dual-axis cervical accelerometry signals in the absence of swallowing but in the ...
Bussone William R - - 2010
Research suggests gender and body size affect head injury tolerance. In this study, angular accelerations and velocities of the head were measured for 18 adult volunteers during typical everyday activities. Peak resultant angular head accelerations and velocities for each subject were compared via T-tests and ANOVAs to determine significant differences ...
Lavergne Louisa - - 2010
In the temporal vicinity of a saccade onset, visual stability is transiently disrupted and briefly flashed visual stimuli undergo a systematic perceptual mislocalization. Specifically, when a stimulus is flashed around saccade onset, localization judgments are grossly biased toward the saccade endpoint. This peri-saccadic compression increases with saccade amplitude. Previous studies ...
Petersik J Timothy - - 2010
Four experiments and controls were run in order to determine the ability of the visual system to detect slight changes in three-dimensional (3D) rotating stimuli in comparison to two-dimensional (2D) controls. A small number of observers (between 5 and 8) viewed computerized displays of pixel-defined transparent rotating spheres or circular ...
Liao Ke K Biomedical Engineering, Daroff-Dell'Osso Laboratory, Veterans Affairs Medical Center and University Hospitals, Case Western Reserve University, Cleveland, OH, - - 2010
During locomotion, head perturbations, consisting of rotations and translations (linear movements), occur with predominant frequencies of 0.5-5.0 Hz. The vestibular reflexes act at short latency to safeguard clear vision and stable posture during locomotion. Much is known about the angular vestibulo-ocular reflex (aVOR) in response to head rotations, which depend ...
Schuler Jeanine R - - 2010
When roll-tilted, the subjective visual vertical (SVV) deviates up to 40 degrees from earth-vertical and trial-to-trial variability increases with head roll. Imperfections in the central processing of visual information were postulated to explain these roll-angle dependent errors. For experimental conditions devoid of visual input, e.g. adjustments of body posture or ...
Seacrist Thomas - - 2010
The Hybrid III 6-year-old ATD has been benchmarked against adult-scaled component level tests but the lack of biomechanical data hinders the effectiveness of the procedures used to scale the adult data to the child. Whole body kinematic validation of the pediatric ATD through limited comparison to post mortem human subjects ...
Petrov Alexander A - - 2010
Perceptual learning was used as a tool for studying motion perception. The pattern of transfer of learning of luminance- (LM) and contrast-modulated (CM) motion is diagnostic of how their respective processing pathways are integrated. Twenty observers practiced fine direction discrimination with either additive (LM) or multiplicative (CM) mixtures of a ...
Patel Ashna - - 2010
We compared thresholds for discriminating spatial frequency for children aged 5, 7, and 9 years, and adults at two baseline spatial frequencies (1 and 3 cpd). In Experiment 1, the minimum change from baseline necessary to detect a change in spatial frequency from either baseline decreased with age from 34% ...
Akamatsu T - - 2010
Dolphins and porpoises have excellent biosonar ability, which they use for navigation, ranging and foraging. However, the role of biosonar in free-ranging small cetaceans has not been fully investigated. The biosonar behaviour and body movements of 15 free-ranging finless porpoises (Neophocaena phocaenoides) were observed using electronic tags attached to the ...
Azat Ch - - 2010
To compare the results of two frequencies of shock waves (1 SW/1 sec. and 1 SW/2 sec.) in the treatment of urolithiasis using the shock wave lithotripsy. SWL is the most frequent modality of the treatment of urolithiasis. The information on a better efficiency of applying shock waves of a ...
Shinder Michael E - - 2010
Vestibular information is an important factor in maintaining accurate spatial awareness. Yet, each of the cortical areas involved in processing vestibular information has unique functionality. Further, the anatomical pathways that provide vestibular input for cognitive processes are also distinct. This review outlines some of the current understanding of vestibular pathways ...
Ghasemzadeh Ali - - 2010
Nowadays, phytochemicals and antioxidants in plants are raising interest in consumers for their roles in the maintenance of human health. Phenolics and flavonoids are known for their health-promoting properties due to protective effects against cardiovascular disease, cancers and other disease. Ginger (Zingiber officinale) is one of the traditional folk medicinal ...
Menzocchi Manuel - - 2010
In highly hypnotizable individuals (highs), postural control is more independent of sensory information than in low hypnotizable subjects (lows). The aim of the study was to find out whether locomotion is also less affected in highs than in lows by visual suppression and changes in the neck proprioceptive input. Eighteen ...
McCandless Cyrus H CH Department of Neurobiology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, - - 2010
The caudal aspect of the parabrachial nucleus (PBN) contains neurons responsive to whole body, periodic rotational stimulation in alert monkeys (Balaban et al. in J Neurophysiol 88:3175-3193, 2002). This study characterizes the angular and linear motion-sensitive response properties of PBN unit responses during off-vertical axis rotation (OVAR) and position trapezoid ...
Day Brian L BL Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK. - - 2010
The left and right vestibular organs always transduce the same signal of head movement, and with natural stimuli can only be activated simultaneously. To investigate how signals from the left and right vestibular organs are integrated to control human balance we electrically modulated the firing of vestibular afferents from each ...
Lewis Richard F RF Department of Otolaryngology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, 243 Charles Street, Boston MA 02114, USA. - - 2010
To investigate vestibuloocular reflex (VOR) adaptation produced by changes in peripheral vestibular afference, we developed and tested a vestibular "prosthesis" that senses yaw-axis angular head velocity and uses this information to modulate the rate of electrical pulses applied to the lateral canal ampullary nerve. The ability of the brain to ...
Tarnutzer A A - - 2010
Precision and accuracy of the subjective visual vertical (SVV) modulate in the roll plane. At large roll angles, systematic SVV errors are biased toward the subject's body-longitudinal axis and SVV precision is decreased. To explain this, SVV models typically implement a bias signal, or a prior, in a head-fixed reference ...
Boker Steven M - - 2009
When people speak with one another, they tend to adapt their head movements and facial expressions in response to each others' head movements and facial expressions. We present an experiment in which confederates' head movements and facial expressions were motion tracked during videoconference conversations, an avatar face was reconstructed in ...
Boeddeker Norbert - - 2010
As animals travel through the environment, powerful reflexes help stabilize their gaze by actively maintaining head and eyes in a level orientation. Gaze stabilization reduces motion blur and prevents image rotations. It also assists in depth perception based on translational optic flow. Here we describe side-to-side flight manoeuvres in honeybees ...
Ortega Laura Jiménez LJ Universidad Complutense de Madrid, Madrid, - - 2009
Many birds show a characteristic forward and backward head movement, while walking, running and sometimes during landing flight, called head bobbing. During the hold phase, the head of the bird remains stable in space, while during the thrust phase, the head is rapidly moved forward. Three main functions for head ...
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