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Sample records for hand eye coordination

  1. Evidence of common and separate eye and hand accumulators underlying flexible eye-hand coordination.

    Science.gov (United States)

    Jana, Sumitash; Gopal, Atul; Murthy, Aditya

    2017-01-01

    Eye and hand movements are initiated by anatomically separate regions in the brain, and yet these movements can be flexibly coupled and decoupled, depending on the need. The computational architecture that enables this flexible coupling of independent effectors is not understood. Here, we studied the computational architecture that enables flexible eye-hand coordination using a drift diffusion framework, which predicts that the variability of the reaction time (RT) distribution scales with its mean. We show that a common stochastic accumulator to threshold, followed by a noisy effector-dependent delay, explains eye-hand RT distributions and their correlation in a visual search task that required decision-making, while an interactive eye and hand accumulator model did not. In contrast, in an eye-hand dual task, an interactive model better predicted the observed correlations and RT distributions than a common accumulator model. Notably, these two models could only be distinguished on the basis of the variability and not the means of the predicted RT distributions. Additionally, signatures of separate initiation signals were also observed in a small fraction of trials in the visual search task, implying that these distinct computational architectures were not a manifestation of the task design per se. Taken together, our results suggest two unique computational architectures for eye-hand coordination, with task context biasing the brain toward instantiating one of the two architectures. Previous studies on eye-hand coordination have considered mainly the means of eye and hand reaction time (RT) distributions. Here, we leverage the approximately linear relationship between the mean and standard deviation of RT distributions, as predicted by the drift-diffusion model, to propose the existence of two distinct computational architectures underlying coordinated eye-hand movements. These architectures, for the first time, provide a computational basis for the flexible

  2. Commentary : Coordination of eye and hand in time and space

    NARCIS (Netherlands)

    Bekkering, H; Sailer, U; Hyona, J; Munoz, DP; Heide, W; Radach, R

    2002-01-01

    Every day of our lives starts with a succession of actions that require eye-hand coordination. From the time we try to turn off the, alarm clock and get dressed, to putting toothpaste on the brush and preparing coffee: all these goal-directed hand movements need to be coordinated with the

  3. Hand-eye coordinative remote maintenance in a tokamak vessel

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Qiang, E-mail: qiu6401@sjtu.edu.cn; Gu, Kai, E-mail: gukai0707@sjtu.edu.cn; Wang, Pengfei, E-mail: wpf790714@163.com; Bai, Weibang, E-mail: 654253204@qq.com; Cao, Qixin, E-mail: qxcao@sjtu.edu.cn

    2016-03-15

    Highlights: • If there is not rotation between the visual coordinate frame (O{sub e}X{sub e}Y{sub e}) and hand coordinate frame (O{sub h}X{sub h}Y{sub h}), a person can coordinate the movement between hand and eye easily. • We establish an alignment between the movement of the operator's hand and the visual scene of the end-effector as displayed on the monitor. • A potential function is set up in a simplified vacuum vessel model to provide a fast collision checking, and the alignment between repulsive force and Omega 7 feedback force is accomplished. • We carry out an experiment to evaluate its performance in a remote handling task. - Abstract: The reliability is vitally important for the remote maintenance in a tokamak vessel. In order to establish a more accurate and safer remote handling system, a hand-eye coordination method and an artificial potential function based collision avoidance method were proposed in this paper. At the end of this paper, these methods were implemented to a bolts tightening maintenance task, which was carried out in our 1/10 scale tokamak model. Experiment results have verified the value of the hand-eye coordination method and the collision avoidance method.

  4. Drawing from memory: hand-eye coordination at multiple scales.

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    Stephanie Huette

    Full Text Available Eyes move to gather visual information for the purpose of guiding behavior. This guidance takes the form of perceptual-motor interactions on short timescales for behaviors like locomotion and hand-eye coordination. More complex behaviors require perceptual-motor interactions on longer timescales mediated by memory, such as navigation, or designing and building artifacts. In the present study, the task of sketching images of natural scenes from memory was used to examine and compare perceptual-motor interactions on shorter and longer timescales. Eye and pen trajectories were found to be coordinated in time on shorter timescales during drawing, and also on longer timescales spanning study and drawing periods. The latter type of coordination was found by developing a purely spatial analysis that yielded measures of similarity between images, eye trajectories, and pen trajectories. These results challenge the notion that coordination only unfolds on short timescales. Rather, the task of drawing from memory evokes perceptual-motor encodings of visual images that preserve coarse-grained spatial information over relatively long timescales as well.

  5. Drawing from Memory: Hand-Eye Coordination at Multiple Scales

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    Spivey, Michael J.

    2013-01-01

    Eyes move to gather visual information for the purpose of guiding behavior. This guidance takes the form of perceptual-motor interactions on short timescales for behaviors like locomotion and hand-eye coordination. More complex behaviors require perceptual-motor interactions on longer timescales mediated by memory, such as navigation, or designing and building artifacts. In the present study, the task of sketching images of natural scenes from memory was used to examine and compare perceptual-motor interactions on shorter and longer timescales. Eye and pen trajectories were found to be coordinated in time on shorter timescales during drawing, and also on longer timescales spanning study and drawing periods. The latter type of coordination was found by developing a purely spatial analysis that yielded measures of similarity between images, eye trajectories, and pen trajectories. These results challenge the notion that coordination only unfolds on short timescales. Rather, the task of drawing from memory evokes perceptual-motor encodings of visual images that preserve coarse-grained spatial information over relatively long timescales as well. PMID:23554894

  6. EFFECT OF PRANAYAMA AND EYE EXERCISES ON EYE TO HAND COORDINATION: STUDY BY FINGER DEXTERITY TEST

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    Nitin

    2015-10-01

    Full Text Available BACKGROUND: Our eyes are bo dy's most well developed sensory organs. Indeed, a far larger part of our brain is devoted to the functions of eyesight than to those of hearing, taste, touch or smell together. We usually take our eyesight for granted, although when vision problems develop, most of us will do everything in our capacity to restore our eyesight to normal . Eyes work together to perceive depth thus allowing us to coordinate with motor actions. Practicing relaxation exercises in the form of pranayama and eye exercise has been shown to improve motor functions and attention. AIM: To study the effect of pranayama and eye exercises on eye to hand coordination. MATERIALS AND METHODS: The present study consisted of 60 healthy subjects divided equally into two groups. One group practiced kapalabhati pranayama and eye exercises for eight weeks whereas other group did not participate in any kind of exercise. The effect of pranayama and eye exercises on eye to hand coordination were assessed by finger dexterity test by using O′Connor finger dexterity task. RESULTS: There was significant improvement in eye to hand coordination in subjects practicing pranayama and eye exercises. Fi nger dexterity test values in study group before and after intervention were 31±4.94 and 33±4.98 respectively. Whereas in control group the values were 29.9±5.7 and 30.1±5.31 respectively. CONCLUSION: Both Kapalabhati pranayama and eye to hand coordination can improve fine motor skills

  7. Geometric computations underlying eye-hand coordination: orientations of the two eyes and the head.

    NARCIS (Netherlands)

    Henriques, D.Y.P.; Medendorp, W.P.; Gielen, C.C.A.M.; Crawford, J.D.

    2003-01-01

    Eye-hand coordination is geometrically complex. To compute the location of a visual target relative to the hand, the brain must consider every anatomical link in the chain from retinas to fingertips. Here we focus on the first three links, studying how the brain handles information about the angles

  8. Geometric computations underlying eye-hand coordination: orientations of the two eyes and the head

    NARCIS (Netherlands)

    Henriques, D.Y.P.; Medendorp, W.P.; Gielen, C.C.A.M.; Crawford, J.D.

    2003-01-01

    Eye-hand coordination is geometrically complex. To compute the location of a visual target relative to the hand, the brain must consider every anatomical link in the chain from retinas to fingertips. Here we focus on the first three links, studying how the brain handles information about the angles

  9. Eye-hand coordination during a double-step task: evidence for a common stochastic accumulator

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    Gopal, Atul

    2015-01-01

    Many studies of reaching and pointing have shown significant spatial and temporal correlations between eye and hand movements. Nevertheless, it remains unclear whether these correlations are incidental, arising from common inputs (independent model); whether these correlations represent an interaction between otherwise independent eye and hand systems (interactive model); or whether these correlations arise from a single dedicated eye-hand system (common command model). Subjects were instructed to redirect gaze and pointing movements in a double-step task in an attempt to decouple eye-hand movements and causally distinguish between the three architectures. We used a drift-diffusion framework in the context of a race model, which has been previously used to explain redirect behavior for eye and hand movements separately, to predict the pattern of eye-hand decoupling. We found that the common command architecture could best explain the observed frequency of different eye and hand response patterns to the target step. A common stochastic accumulator for eye-hand coordination also predicts comparable variances, despite significant difference in the means of the eye and hand reaction time (RT) distributions, which we tested. Consistent with this prediction, we observed that the variances of the eye and hand RTs were similar, despite much larger hand RTs (∼90 ms). Moreover, changes in mean eye RTs, which also increased eye RT variance, produced a similar increase in mean and variance of the associated hand RT. Taken together, these data suggest that a dedicated circuit underlies coordinated eye-hand planning. PMID:26084906

  10. A Turbo Pascal program for testing eye-hand coordination by means of tracing.

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    Indra, M

    1992-02-01

    A Turbo Pascal program for eye-hand coordination testing using standard PC XT/AT mouse is presented. The contour segments of three simple figures (square, circle and triangle) are chosen as tracing trajectories. Tracing performance expressed in root mean squared (RMS) and modulus mean error (MME) measures are calculated and used, together with tracing time for evaluation of eye hand coordination ability.

  11. Coordinated control of eye and hand movements in dynamic reaching

    NARCIS (Netherlands)

    Neggers, S.F.W.; Bekkering, H.

    2002-01-01

    In the present study, we integrated two recent, at first sight contradictory findings regarding the question whether saccadic eye movements can be generated to a newly presented target during an ongoing hand movement. Saccades were measured during so-called adaptive and sustained pointing

  12. An Infant Development-inspired Approach to Robot Hand-eye Coordination

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    Fei Chao

    2014-02-01

    Full Text Available This paper presents a novel developmental learning approach for hand-eye coordination in an autonomous robotic system. Robotic hand-eye coordination plays an important role in dealing with real-time environments. Under the approach, infant developmental patterns are introduced to build our robot's learning system. The method works by first constructing a brain-like computational structure to control the robot, and then by using infant behavioural patterns to build a hand-eye coordination learning algorithm. This work is supported by an experimental evaluation, which shows that the control system is implemented simply, and that the learning approach provides fast and incremental learning of behavioural competence.

  13. Eye-hand coordination during dynamic visuomotor rotations.

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    Lorenzo Masia

    Full Text Available BACKGROUND: for many technology-driven visuomotor tasks such as tele-surgery, human operators face situations in which the frames of reference for vision and action are misaligned and need to be compensated in order to perform the tasks with the necessary precision. The cognitive mechanisms for the selection of appropriate frames of reference are still not fully understood. This study investigated the effect of changing visual and kinesthetic frames of reference during wrist pointing, simulating activities typical for tele-operations. METHODS: using a robotic manipulandum, subjects had to perform center-out pointing movements to visual targets presented on a computer screen, by coordinating wrist flexion/extension with abduction/adduction. We compared movements in which the frames of reference were aligned (unperturbed condition with movements performed under different combinations of visual/kinesthetic dynamic perturbations. The visual frame of reference was centered to the computer screen, while the kinesthetic frame was centered around the wrist joint. Both frames changed their orientation dynamically (angular velocity = 36 degrees /s with respect to the head-centered frame of reference (the eyes. Perturbations were either unimodal (visual or kinesthetic, or bimodal (visual+kinesthetic. As expected, pointing performance was best in the unperturbed condition. The spatial pointing error dramatically worsened during both unimodal and most bimodal conditions. However, in the bimodal condition, in which both disturbances were in phase, adaptation was very fast and kinematic performance indicators approached the values of the unperturbed condition. CONCLUSIONS: this result suggests that subjects learned to exploit an "affordance" made available by the invariant phase relation between the visual and kinesthetic frames. It seems that after detecting such invariance, subjects used the kinesthetic input as an informative signal rather than a

  14. Movement-related activity in the periarcuate cortex of monkeys during coordinated eye and hand movements.

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    Kurata, Kiyoshi

    2017-09-20

    To determine the role of the periarcuate cortex during coordinated eye and hand movements in monkeys, the present study examined neuronal activity in this region during movement with the hand, eyes, or both as effectors toward a visuospatial target. Similar to the primary motor cortex (M1), the dorsal premotor cortex contained a higher proportion of neurons that were closely related to hand movements, whereas saccade-related neurons were frequently recorded from the frontal eye field (FEF). Interestingly, neurons that exhibited activity related to both eye and hand movements were recorded most frequently in the ventral premotor cortex (PMv), located between the FEF and M1. Neuronal activity in the periarcuate cortex was highly modulated during coordinated movements compared to either eye or hand movement only. Additionally, a small number of neurons were active specifically during one of the three task modes, which could be dissociated from the effector activity. In this case, neuron onset was either ahead of or behind the onset of eye and/or hand movement, and some neuronal activity lasted until reward delivery signaled successful completion of reaching. The present findings indicate that the periarcuate cortex, particularly the PMv, plays important roles in orchestrating coordinated movements from the initiation to the termination of reaching. Copyright © 2017, Journal of Neurophysiology.

  15. Hand/Eye Coordination For Fine Robotic Motion

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    Lokshin, Anatole M.

    1992-01-01

    Fine motions of robotic manipulator controlled with help of visual feedback by new method reducing position errors by order of magnitude. Robotic vision subsystem includes five cameras: three stationary ones providing wide-angle views of workspace and two mounted on wrist of auxiliary robot arm. Stereoscopic cameras on arm give close-up views of object and end effector. Cameras measure errors between commanded and actual positions and/or provide data for mapping between visual and manipulator-joint-angle coordinates.

  16. Joint attention without gaze following: human infants and their parents coordinate visual attention to objects through eye-hand coordination.

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    Chen Yu

    Full Text Available The coordination of visual attention among social partners is central to many components of human behavior and human development. Previous research has focused on one pathway to the coordination of looking behavior by social partners, gaze following. The extant evidence shows that even very young infants follow the direction of another's gaze but they do so only in highly constrained spatial contexts because gaze direction is not a spatially precise cue as to the visual target and not easily used in spatially complex social interactions. Our findings, derived from the moment-to-moment tracking of eye gaze of one-year-olds and their parents as they actively played with toys, provide evidence for an alternative pathway, through the coordination of hands and eyes in goal-directed action. In goal-directed actions, the hands and eyes of the actor are tightly coordinated both temporally and spatially, and thus, in contexts including manual engagement with objects, hand movements and eye movements provide redundant information about where the eyes are looking. Our findings show that one-year-olds rarely look to the parent's face and eyes in these contexts but rather infants and parents coordinate looking behavior without gaze following by attending to objects held by the self or the social partner. This pathway, through eye-hand coupling, leads to coordinated joint switches in visual attention and to an overall high rate of looking at the same object at the same time, and may be the dominant pathway through which physically active toddlers align their looking behavior with a social partner.

  17. Limited Contribution of Primary Motor Cortex in Eye-Hand Coordination: A TMS Study.

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    Mathew, James; Eusebio, Alexandre; Danion, Frederic

    2017-10-04

    The ability to track a moving target with the eye is substantially improved when the target is self-moved compared with when it is moved by an external agent. To account for this observation, it has been postulated that the oculomotor system has access to hand efference copy, thereby allowing to predict the motion of the visual target. Along this scheme, we tested the effect of transcranial magnetic stimulation (TMS) over the hand area of the primary motor cortex (M1) when human participants (50% females) are asked to track with their eyes a visual target whose horizontal motion is driven by their grip force. We reasoned that, if the output of M1 is used by the oculomotor system to keep track of the target, on top of inducing short latency disturbance of grip force, single-pulse TMS should also quickly disrupt ongoing eye motion. For comparison purposes, the effect of TMS over M1 was monitored when subjects tracked an externally moved target (while keeping their hand at rest or not). In both cases, results showed no alterations in smooth pursuit, meaning that its velocity was unaffected within the 25-125 ms epoch that followed TMS. Overall, our results imply that the output of M1 has limited contribution in driving the eye motion during our eye-hand coordination task. This study suggests that, if hand motor signals are accessed by the oculomotor system, this is upstream of M1.SIGNIFICANCE STATEMENT The ability to coordinate eye and hand actions is central in everyday activity. However, the neural mechanisms underlying this coordination remain to be clarified. A leading hypothesis is that the oculomotor system has access to hand motor signals. Here we explored this possibility by means of transcranial magnetic stimulation (TMS) over the hand area of the primary motor cortex (M1) when humans tracked with the eyes a visual target that was moved by the hand. As expected, ongoing hand action was perturbed 25-30 ms after TMS, but our results fail to show any disruption

  18. Three-dimensional binocular eye-hand coordination in normal vision and with simulated visual impairment.

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    Maiello, Guido; Kwon, MiYoung; Bex, Peter J

    2018-01-03

    Sensorimotor coupling in healthy humans is demonstrated by the higher accuracy of visually tracking intrinsically-rather than extrinsically-generated hand movements in the fronto-parallel plane. It is unknown whether this coupling also facilitates vergence eye movements for tracking objects in depth, or can overcome symmetric or asymmetric binocular visual impairments. Human observers were therefore asked to track with their gaze a target moving horizontally or in depth. The movement of the target was either directly controlled by the observer's hand or followed hand movements executed by the observer in a previous trial. Visual impairments were simulated by blurring stimuli independently in each eye. Accuracy was higher for self-generated movements in all conditions, demonstrating that motor signals are employed by the oculomotor system to improve the accuracy of vergence as well as horizontal eye movements. Asymmetric monocular blur affected horizontal tracking less than symmetric binocular blur, but impaired tracking in depth as much as binocular blur. There was a critical blur level up to which pursuit and vergence eye movements maintained tracking accuracy independent of blur level. Hand-eye coordination may therefore help compensate for functional deficits associated with eye disease and may be employed to augment visual impairment rehabilitation.

  19. Eye-Hand Coordination during Visuomotor Adaptation with Different Rotation Angles

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    Rentsch, Sebastian; Rand, Miya K.

    2014-01-01

    This study examined adaptive changes of eye-hand coordination during a visuomotor rotation task. Young adults made aiming movements to targets on a horizontal plane, while looking at the rotated feedback (cursor) of hand movements on a monitor. To vary the task difficulty, three rotation angles (30°, 75°, and 150°) were tested in three groups. All groups shortened hand movement time and trajectory length with practice. However, control strategies used were different among groups. The 30° group used proportionately more implicit adjustments of hand movements than other groups. The 75° group used more on-line feedback control, whereas the 150° group used explicit strategic adjustments. Regarding eye-hand coordination, timing of gaze shift to the target was gradually changed with practice from the late to early phase of hand movements in all groups, indicating an emerging gaze-anchoring behavior. Gaze locations prior to the gaze anchoring were also modified with practice from the cursor vicinity to an area between the starting position and the target. Reflecting various task difficulties, these changes occurred fastest in the 30° group, followed by the 75° group. The 150° group persisted in gazing at the cursor vicinity. These results suggest that the function of gaze control during visuomotor adaptation changes from a reactive control for exploring the relation between cursor and hand movements to a predictive control for guiding the hand to the task goal. That gaze-anchoring behavior emerged in all groups despite various control strategies indicates a generality of this adaptive pattern for eye-hand coordination in goal-directed actions. PMID:25333942

  20. Eye-hand coordination during visuomotor adaptation with different rotation angles.

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    Sebastian Rentsch

    Full Text Available This study examined adaptive changes of eye-hand coordination during a visuomotor rotation task. Young adults made aiming movements to targets on a horizontal plane, while looking at the rotated feedback (cursor of hand movements on a monitor. To vary the task difficulty, three rotation angles (30°, 75°, and 150° were tested in three groups. All groups shortened hand movement time and trajectory length with practice. However, control strategies used were different among groups. The 30° group used proportionately more implicit adjustments of hand movements than other groups. The 75° group used more on-line feedback control, whereas the 150° group used explicit strategic adjustments. Regarding eye-hand coordination, timing of gaze shift to the target was gradually changed with practice from the late to early phase of hand movements in all groups, indicating an emerging gaze-anchoring behavior. Gaze locations prior to the gaze anchoring were also modified with practice from the cursor vicinity to an area between the starting position and the target. Reflecting various task difficulties, these changes occurred fastest in the 30° group, followed by the 75° group. The 150° group persisted in gazing at the cursor vicinity. These results suggest that the function of gaze control during visuomotor adaptation changes from a reactive control for exploring the relation between cursor and hand movements to a predictive control for guiding the hand to the task goal. That gaze-anchoring behavior emerged in all groups despite various control strategies indicates a generality of this adaptive pattern for eye-hand coordination in goal-directed actions.

  1. Effects of induced monocular blur versus anisometropic amblyopia on saccades, reaching, and eye-hand coordination.

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    Niechwiej-Szwedo, Ewa; Kennedy, Sean A; Colpa, Linda; Chandrakumar, Manokaraananthan; Goltz, Herbert C; Wong, Agnes M F

    2012-07-01

    We previously showed that anisometropic amblyopia affects the programming and execution of saccades and reaching movements. In our current study, we investigated whether these amblyopia-related changes simply are due to a reduction in visual acuity alone by inducing artificial blur in one eye in visually-normal participants. Twelve visually-normal participants performed saccades and reach-to-touch movements to targets presented on a computer screen during binocular and monocular viewing. A contact lens was used to blur the vision of one eye to a mean acuity level of 20/50. Saccades and reaching kinematics were compared before blur, immediately after blur, and 5 hours after blur was induced. The 5 hours after blur kinematic data from visually-normal participants also were compared to those from 12 patients with anisometropic amblyopia who had comparable acuity in the amblyopic eye. Primary saccades (latency, amplitude, peak velocity), reaching movements (reaction time, movement time, peak acceleration, duration of the acceleration phase), and eye-hand coordination (saccade-to-reach planning interval, saccade-to-reach peak velocity interval) were not affected by induced monocular blur in visually-normal participants, either immediately or 5 hours after blur. Compared to visually-normal participants after 5 hours of blur, patients with anisometropic amblyopia had significantly longer and more variable saccade latency during amblyopic eye viewing, lower peak acceleration, and a longer acceleration phase during reaching, and a different temporal pattern of eye-hand coordination. Artificially-induced monocular blur in visually-normal participants did not affect saccades, reaching movements, and eye-hand coordination during a simple reach-to-touch task even after a period of blur exposure. In contrast, patients with anisometropic amblyopia demonstrated significantly different kinematics while performing the same task. These results indicate that loss of visual acuity

  2. CORRELATION BETWEEN CORE MUSCLE STRENGTH AND HAND-EYE COORDINATION IN NON ATHLETES

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    Anusha Reddy

    2017-10-01

    Full Text Available Background: The trunk plays a vital role in limb excursion and manipulation. Hence core muscle strength invariably affects the performance of the upper extremity skills. Thus this study tried to determine the correlation between core muscle strength and hand-eye coordination in non-athletes with low back pain. Methods: 20 nonathletic subjects with low back pain were selected based on the selection criteria. Day 1 core muscle strength was assessed using Plank Test and Sorensen Test. Day 2 hand-eye coordination was assessed using Alternate Wall Toss Test and Simultaneous Ball Throw Test. A rest period of 2 hours was given between both the tests. Results: Pearson’s Correlation analysis was doe to find the relationship between the scales. The correlation analysis of plank test and AWT reveled r = 0.8 with significant difference (p <0.003. The analysis of plank test and SBT revealed r=0.7 with significant difference (p <0.011. The correlation analysis of Sorensen test and AWT revealed r= 0.8 with significant difference (p <0.008. The analysis of Sorensen Test and SBT revealed r=0.7 with significant difference (p<0.005. Conclusion: This study concludes that there is a strong positive correlation between the Core Muscle Strength and Hand-Eye Coordination in nonathletes with Low Back Pain

  3. Effects of hand termination and accuracy constraint on eye-hand coordination during sequential two-segment movements.

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    Rand, Miya K; Stelmach, George E

    2010-12-01

    The purpose of this study was to examine the effects of accuracy constraints and termination requirements of hand movement on eye-hand coordination. Healthy adults performed two-segment eye and hand aiming movements to predetermined stationary targets. While two-segment eye movements were made to the first and second targets for all conditions, hand movements were varied across conditions. The first segment had two target sizes to alter accuracy constraints. There were three hand movement types with different termination requirements: (1) stop both at the first and at the second targets, (2) stop at the first target and discontinue, and (3) move through the first target and discontinue. The results showed that the initiation of saccades was moderately correlated with the initiation of hand movements, and both initiations changed in a similar fashion depending on various hand termination requirements. Amplitude of primary saccades and frequency of corrective saccades during the first segment were affected by the combined effects of accuracy constraints and hand termination requirements. These results suggest that the planning and execution of saccades are based in part on global task constraints related to the accuracy and termination demands of hand movements over the two segments. During the transition from the first to the second segment, the gaze was held on the first target until shortly after the pointing to that target was terminated, showing gaze anchoring. The gaze anchoring was prolonged due to the increased accuracy constraint of that target or by including pointing to the second target. However, the gaze anchoring was broken prior to the completion of pointing when the accuracy constraint was reduced and pointing to the second target was excluded. The observed modifications of gaze anchoring imply that the oculomotor system is functionally obligated to fixate a gaze to a pointing target only to the extent that successful completion of a pointing task is

  4. Eye-Hand Coordination in Children with High Functioning Autism and Asperger's Disorder Using a Gap-Overlap Paradigm

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    Crippa, Alessandro; Forti, Sara; Perego, Paolo; Molteni, Massimo

    2013-01-01

    We investigated eye-hand coordination in children with autism spectrum disorders (ASD) in comparison with age-matched normally developing peers. The eye-hand correlation was measured by putting fixation latencies in relation with pointing and key pressing responses in visual detection tasks where a gap-overlap paradigm was used and compared to…

  5. Very slow search and reach: failure to maximize expected gain in an eye-hand coordination task.

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    Hang Zhang

    Full Text Available We examined an eye-hand coordination task where optimal visual search and hand movement strategies were inter-related. Observers were asked to find and touch a target among five distractors on a touch screen. Their reward for touching the target was reduced by an amount proportional to how long they took to locate and reach to it. Coordinating the eye and the hand appropriately would markedly reduce the search-reach time. Using statistical decision theory we derived the sequence of interrelated eye and hand movements that would maximize expected gain and we predicted how hand movements should change as the eye gathered further information about target location. We recorded human observers' eye movements and hand movements and compared them with the optimal strategy that would have maximized expected gain. We found that most observers failed to adopt the optimal search-reach strategy. We analyze and describe the strategies they did adopt.

  6. Dynamic modulation of illusory and physical target size on separate and coordinated eye and hand movements.

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    Gamble, Christine M; Song, Joo-Hyun

    2017-03-01

    In everyday behavior, two of the most common visually guided actions-eye and hand movements-can be performed independently, but are often synergistically coupled. In this study, we examine whether the same visual representation is used for different stages of saccades and pointing, namely movement preparation and execution, and whether this usage is consistent between independent and naturalistic coordinated eye and hand movements. To address these questions, we used the Ponzo illusion to dissociate the perceived and physical sizes of visual targets and measured the effects on movement preparation and execution for independent and coordinated saccades and pointing. During independent movements, we demonstrated that both physically and perceptually larger targets produced faster preparation for both effectors. Furthermore, participants who showed a greater influence of the illusion on saccade preparation also showed a greater influence on pointing preparation, suggesting that a shared mechanism involved in preparation across effectors is influenced by illusions. However, only physical but not perceptual target sizes influenced saccade and pointing execution. When pointing was coordinated with saccades, we observed different dynamics: pointing no longer showed modulation from illusory size, while saccades showed illusion modulation for both preparation and execution. Interestingly, in independent and coordinated movements, the illusion modulated saccade preparation more than pointing preparation, with this effect more pronounced during coordination. These results suggest a shared mechanism, dominated by the eyes, may underlie visually guided action preparation across effectors. Furthermore, the influence of illusions on action may operate within such a mechanism, leading to dynamic interactions between action modalities based on task demands.

  7. Effects of strabismic amblyopia and strabismus without amblyopia on visuomotor behavior: III. Temporal eye-hand coordination during reaching

    National Research Council Canada - National Science Library

    Niechwiej-Szwedo, Ewa; Goltz, Herbert C; Chandrakumar, Manokaraananthan; Wong, Agnes M F

    2014-01-01

    To examine the effects of strabismic amblyopia and strabismus only, without amblyopia, on the temporal patterns of eye-hand coordination during both the planning and execution stages of visually-guided reaching. Forty-six adults...

  8. Active collisions in altered gravity reveal eye-hand coordination strategies.

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    Olivier White

    Full Text Available Most object manipulation tasks involve a series of actions demarcated by mechanical contact events, and gaze is usually directed to the locations of these events as the task unfolds. Typically, gaze foveates the target 200 ms in advance of the contact. This strategy improves manual accuracy through visual feedback and the use of gaze-related signals to guide the hand/object. Many studies have investigated eye-hand coordination in experimental and natural tasks; most of them highlighted a strong link between eye movements and hand or object kinematics. In this experiment, we analyzed gaze strategies in a collision task but in a very challenging dynamical context. Participants performed collisions while they were exposed to alternating episodes of microgravity, hypergravity and normal gravity. First, by isolating the effects of inertia in microgravity, we found that peak hand acceleration marked the transition between two modes of grip force control. Participants exerted grip forces that paralleled load force profiles, and then increased grip up to a maximum shifted after the collision. Second, we found that the oculomotor strategy adapted visual feedback of the controlled object around the collision, as demonstrated by longer durations of fixation after collision in new gravitational environments. Finally, despite large variability of arm dynamics in altered gravity, we found that saccades were remarkably time-locked to the peak hand acceleration in all conditions. In conclusion, altered gravity allowed light to be shed on predictive mechanisms used by the central nervous system to coordinate gaze, hand and grip motor actions during a mixed task that involved transport of an object and high impact loads.

  9. Saccade-Related Potentials During Eye-Hand Coordination: Effects of Hand Movements on Saccade Preparation.

    Science.gov (United States)

    Sailer, Uta; Güldenpfennig, Florian; Eggert, Thomas

    2016-07-01

    This study investigated the effect of hand movements on behavioral and electrophysiological parameters of saccade preparation. While event-related potentials were recorded in 17 subjects, they performed saccades to a visual target either together with a hand movement in the same direction, a hand movement in the opposite direction, a hand movement to a third, independent direction, or without any accompanying hand movements. Saccade latencies increased with any kind of accompanying hand movement. Both saccade and manual latencies were largest when both movements aimed at opposite directions. In contrast, saccade-related potentials indicating preparatory activity were mainly affected by hand movements in the same direction. The data suggest that concomitant hand movements interfere with saccade preparation, particularly when the two movements involve motor preparations that access the same visual stimulus. This indicates that saccade preparation is continually informed about hand movement preparation.

  10. Playing checkers: detection and eye hand coordination in simulated prosthetic vision

    Science.gov (United States)

    Dagnelie, Gislin; Walter, Matthias; Yang, Liancheng

    2006-09-01

    In order to assess the potential for visual inspection and eye hand coordination without tactile feedback under conditions that may be available to future retinal prosthesis wearers, we studied the ability of sighted individuals to act upon pixelized visual information at very low resolution, equivalent to 20/2400 visual acuity. Live images from a head-mounted camera were low-pass filtered and presented in a raster of 6 × 10 circular Gaussian dots. Subjects could either freely move their gaze across the raster (free-viewing condition) or the raster position was locked to the subject's gaze by means of video-based pupil tracking (gaze-locked condition). Four normally sighted and one severely visually impaired subject with moderate nystagmus participated in a series of four experiments. Subjects' task was to count 1 to 16 white fields randomly distributed across an otherwise black checkerboard (counting task) or to place a black checker on each of the white fields (placing task). We found that all subjects were capable of learning both tasks after varying amounts of practice, both in the free-viewing and in the gaze-locked conditions. Normally sighted subjects all reached very similar performance levels independent of the condition. The practiced performance level of the visually impaired subject in the free-viewing condition was indistinguishable from that of the normally sighted subjects, but required approximately twice the amount of time to place checkers in the gaze-locked condition; this difference is most likely attributable to this subject's nystagmus. Thus, if early retinal prosthesis wearers can achieve crude form vision, then on the basis of these results they too should be able to perform simple eye hand coordination tasks without tactile feedback.

  11. Eye-Hand Coordination during Visuomotor Adaptation with Different Rotation Angles: Effects of Terminal Visual Feedback.

    Directory of Open Access Journals (Sweden)

    Miya K Rand

    Full Text Available This study examined adaptive changes of eye-hand coordination during a visuomotor rotation task under the use of terminal visual feedback. Young adults made reaching movements to targets on a digitizer while looking at targets on a monitor where the rotated feedback (a cursor of hand movements appeared after each movement. Three rotation angles (30°, 75° and 150° were examined in three groups in order to vary the task difficulty. The results showed that the 30° group gradually reduced direction errors of reaching with practice and adapted well to the visuomotor rotation. The 75° group made large direction errors of reaching, and the 150° group applied a 180° reversal shift from early practice. The 75°and 150° groups, however, overcompensated the respective rotations at the end of practice. Despite these group differences in adaptive changes of reaching, all groups gradually adapted gaze directions prior to reaching from the target area to the areas related to the final positions of reaching during the course of practice. The adaptive changes of both hand and eye movements in all groups mainly reflected adjustments of movement directions based on explicit knowledge of the applied rotation acquired through practice. Only the 30° group showed small implicit adaptation in both effectors. The results suggest that by adapting gaze directions from the target to the final position of reaching based on explicit knowledge of the visuomotor rotation, the oculomotor system supports the limb-motor system to make precise preplanned adjustments of reaching directions during learning of visuomotor rotation under terminal visual feedback.

  12. Keep your head on straight: facilitating sensori-motor transformations for eye-hand coordination.

    Science.gov (United States)

    Tagliabue, M; Arnoux, L; McIntyre, J

    2013-09-17

    In many day-to-day situations humans manifest a marked tendency to hold the head vertical while performing sensori-motor actions. For instance, when performing coordinated whole-body motor tasks, such as skiing, gymnastics or simply walking, and even when driving a car, human subjects will strive to keep the head aligned with the gravito-inertial vector. Until now, this phenomenon has been thought of as a means to limit variations of sensory signals emanating from the eyes and inner ears. Recent theories suggest that for the task of aligning the hand to a target, the CNS compares target and hand concurrently in both visual and kinesthetic domains, rather than combining sensory data into a single, multimodal reference frame. This implies that when sensory information is lacking in one modality, it must be 'reconstructed' based on information from the other. Here we asked subjects to reach to a visual target with the unseen hand. In this situation, the CNS might reconstruct the orientation of the target in kinesthetic space or reconstruct the orientation of the hand in visual space, or both. By having subjects tilt the head during target acquisition or during movement execution, we show a greater propensity to perform the sensory reconstruction that can be achieved when the head is held upright. These results suggest that the reason humans tend to keep their head upright may also have to do with how the brain manipulates and stores spatial information between reference frames and between sensory modalities, rather than only being tied to the specific problem of stabilizing visual and vestibular inputs. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. Eye-hand coordination during manual object transport with the affected and less affected hand in adolescents with hemiparetic cerebral palsy

    NARCIS (Netherlands)

    Verrel, J.; Bekkering, H.; Steenbergen, B.

    2008-01-01

    In the present study we investigated eye-hand coordination in adolescents with hemiparetic cerebral palsy (CP) and neurologically healthy controls. Using an object prehension and transport task, we addressed two hypotheses, motivated by the question whether early brain damage and the ensuing

  14. Does physical education influence eye-hand coordination? The Lifestyles of our Kids intervention study.

    Science.gov (United States)

    Wicks, L J; Telford, R M; Cunningham, R B; Semple, S J; Telford, R D

    2017-12-01

    In Australian government-funded primary schools, the responsibility for physical education (PE) falls mainly on general classroom teachers, many of whom possess limited PE training. This study sought to examine the impact of specialist-taught PE on eye-hand coordination (EHC) development. In this 4-year cluster-randomized intervention, participants were 187 boys and 172 girls initially in grade 2 in 29 primary schools, where no school employed university-trained specialist PE teachers. In 13 (intervention) schools, specialist PE teachers conducted 268 PE classes (two 45-minute sessions/wk) from grade 2 to grade 6. The intervention was based on traditional PE educational objectives, including fundamental motor skills, but did not specifically focus on EHC. The remaining 16 (control) schools continued with common-practice PE taught by general classroom teachers (30-60 min/wk). EHC was measured by a ball throw and wall-rebound catch test and recorded at ages 8, 10, and 12 (SD 0.3) at ends of grades 2, 4, and 6, respectively. There was steady yearly improvement of EHC in both groups, but no evidence of any intervention effect in boys (P=.88) or girls (P=.20). The introduction of specialist-taught PE during 4 years of primary school did not influence EHC development. Considering evidence that classroom teachers make little contribution to PE in this jurisdiction, together with the steady progression of EHC over the 4 years, other influences such as organized sport, after-school activities, natural development, and parental instruction are conceivably more influential factors in EHC development during primary school years. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Effects of strabismic amblyopia and strabismus without amblyopia on visuomotor behavior: III. Temporal eye-hand coordination during reaching.

    Science.gov (United States)

    Niechwiej-Szwedo, Ewa; Goltz, Herbert C; Chandrakumar, Manokaraananthan; Wong, Agnes M F

    2014-11-11

    To examine the effects of strabismic amblyopia and strabismus only, without amblyopia, on the temporal patterns of eye-hand coordination during both the planning and execution stages of visually-guided reaching. Forty-six adults (16 with strabismic amblyopia, 14 with strabismus only, and 16 visually normal) executed reach-to-touch movements toward targets presented randomly 5° or 10° to the left or right of central fixation. Viewing conditions were binocular, monocular viewing with the amblyopic eye, and monocular viewing with the fellow eye (dominant and nondominant viewing for participants without amblyopia). Temporal coordination between eye and hand movements was examined during reach planning (interval between the initiation of saccade and reaching, i.e., saccade-to-reach planning interval) and reach execution (interval between the initiation of saccade and reach peak velocity [PV], i.e., saccade-to-reach PV interval). The frequency and dynamics of secondary reach-related saccades were also examined. The temporal patterns of eye-hand coordination prior to reach initiation were comparable among participants with strabismic amblyopia, strabismus only, and visually normal adults. However, the reach acceleration phase of participants with strabismic amblyopia and those with strabismus only were longer following target fixation (saccade-to-reach PV interval) than that of visually normal participants (P amblyopia with different levels of acuity and stereo acuity loss. Participants with strabismic amblyopia and strabismus only initiated secondary reach-related saccades significantly more frequently than visually normal participants. The amplitude and peak velocity of these saccades were significantly greater during amblyopic eye viewing in participants with amblyopia who also had negative stereopsis. Adults with strabismic amblyopia and strabismus only showed an altered pattern of temporal eye-hand coordination during the reach acceleration phase, which might

  16. Multiple Coordinate Systems and Motor Strategies for Reaching Movements When Eye and Hand Are Dissociated in Depth and Direction

    Directory of Open Access Journals (Sweden)

    Annalisa Bosco

    2017-06-01

    Full Text Available Reaching behavior represents one of the basic aspects of human cognitive abilities important for the interaction with the environment. Reaching movements towards visual objects are controlled by mechanisms based on coordinate systems that transform the spatial information of target location into appropriate motor response. Although recent works have extensively studied the encoding of target position for reaching in three-dimensional space at behavioral level, the combined analysis of reach errors and movement variability has so far been investigated by few studies. Here we did so by testing 12 healthy participants in an experiment where reaching targets were presented at different depths and directions in foveal and peripheral viewing conditions. Each participant executed a memory-guided task in which he/she had to reach the memorized position of the target. A combination of vector and gradient analysis, novel for behavioral data, was applied to analyze patterns of reach errors for different combinations of eye/target positions. The results showed reach error patterns based on both eye- and space-centered coordinate systems: in depth more biased towards a space-centered representation and in direction mixed between space- and eye-centered representation. We calculated movement variability to describe different trajectory strategies adopted by participants while reaching to the different eye/target configurations tested. In direction, the distribution of variability between configurations that shared the same eye/target relative configuration was different, whereas in configurations that shared the same spatial position of targets, it was similar. In depth, the variability showed more similar distributions in both pairs of eye/target configurations tested. These results suggest that reaching movements executed in geometries that require hand and eye dissociations in direction and depth showed multiple coordinate systems and different trajectory

  17. Multiple Coordinate Systems and Motor Strategies for Reaching Movements When Eye and Hand Are Dissociated in Depth and Direction

    Science.gov (United States)

    Bosco, Annalisa; Piserchia, Valentina; Fattori, Patrizia

    2017-01-01

    Reaching behavior represents one of the basic aspects of human cognitive abilities important for the interaction with the environment. Reaching movements towards visual objects are controlled by mechanisms based on coordinate systems that transform the spatial information of target location into appropriate motor response. Although recent works have extensively studied the encoding of target position for reaching in three-dimensional space at behavioral level, the combined analysis of reach errors and movement variability has so far been investigated by few studies. Here we did so by testing 12 healthy participants in an experiment where reaching targets were presented at different depths and directions in foveal and peripheral viewing conditions. Each participant executed a memory-guided task in which he/she had to reach the memorized position of the target. A combination of vector and gradient analysis, novel for behavioral data, was applied to analyze patterns of reach errors for different combinations of eye/target positions. The results showed reach error patterns based on both eye- and space-centered coordinate systems: in depth more biased towards a space-centered representation and in direction mixed between space- and eye-centered representation. We calculated movement variability to describe different trajectory strategies adopted by participants while reaching to the different eye/target configurations tested. In direction, the distribution of variability between configurations that shared the same eye/target relative configuration was different, whereas in configurations that shared the same spatial position of targets, it was similar. In depth, the variability showed more similar distributions in both pairs of eye/target configurations tested. These results suggest that reaching movements executed in geometries that require hand and eye dissociations in direction and depth showed multiple coordinate systems and different trajectory strategies according

  18. Gain-of-function mutations in the K(ATP channel (KCNJ11 impair coordinated hand-eye tracking.

    Directory of Open Access Journals (Sweden)

    James S McTaggart

    Full Text Available Gain-of-function mutations in the ATP-sensitive potassium channel can cause permanent neonatal diabetes mellitus (PNDM or neonatal diabetes accompanied by a constellation of neurological symptoms (iDEND syndrome. Studies of a mouse model of iDEND syndrome revealed that cerebellar Purkinje cell electrical activity was impaired and that the mice exhibited poor motor coordination. In this study, we probed the hand-eye coordination of PNDM and iDEND patients using visual tracking tasks to see if poor motor coordination is also a feature of the human disease.Control participants (n = 14, patients with iDEND syndrome (n = 6 or 7, and patients with PNDM (n = 7 completed three computer-based tasks in which a moving target was tracked with a joystick-controlled cursor. Patients with PNDM and iDEND were being treated with sulphonylurea drugs at the time of testing.No differences were seen between PNDM patients and controls. Patients with iDEND syndrome were significantly less accurate than controls in two of the three tasks. The greatest differences were seen when iDEND patients tracked blanked targets, i.e. when predictive tracking was required. In this task, iDEND patients incurred more discrepancy errors (p = 0.009 and more velocity errors (p= 0.009 than controls.These results identify impaired hand-eye coordination as a new clinical feature of iDEND. The aetiology of this feature is likely to involve cerebellar dysfunction. The data further suggest that sulphonylurea doses that control the diabetes of these patients may be insufficient to fully correct their neurological symptoms.

  19. The role of the posterior parietal cortex in stereopsis and hand-eye coordination during motor task behaviours.

    Science.gov (United States)

    Paggetti, Giulia; Leff, Daniel Richard; Orihuela-Espina, Felipe; Mylonas, George; Darzi, Ara; Yang, Guang-Zhong; Menegaz, Gloria

    2015-05-01

    The field of 'Neuroergonomics' has the potential to improve safety in high-risk operative environments through a better appreciation of the way in which the brain responds during human-tool interactions. This is especially relevant to minimally invasive surgery (MIS). Amongst the many challenges imposed on the surgeon by traditional MIS (laparoscopy), arguably the greatest is the loss of depth perception. Robotic MIS platforms, on the other hand, provide the surgeon with a magnified three-dimensional view of the environment, and as a result may offload a degree of the cognitive burden. The posterior parietal cortex (PPC) plays an integral role in human depth perception. Therefore, it can be hypothesized that differences in PPC activation between monoscopic and stereoscopic vision may be observed. In order to investigate this hypothesis, the current study explores disparities in PPC responses between monoscopic and stereoscopic visual perception to better de-couple the burden imposed by laparoscopy and robotic surgery on the operator's brain. Fourteen participants conducted tasks of depth perception and hand-eye coordination under both monoscopic and stereoscopic visual feedback. Cortical haemodynamic responses were monitored throughout using optical functional neuroimaging. Overall, recruitment of the bilateral superior parietal lobule was observed during both depth perception and hand-eye coordination tasks. This occurred contrary to our hypothesis, regardless of the mode of visual feedback. Operator technical performance was significantly different in two- and three-dimensional visual displays. These differences in technical performance do not appear to be explained by significant differences in parietal lobe processing.

  20. Active collisions in altered gravity reveal eye-hand coordination strategies

    National Research Council Canada - National Science Library

    White, Olivier; Lefèvre, Philippe; Wing, Alan M; Bracewell, R Martyn; Thonnard, Jean-Louis

    2012-01-01

    .... Typically, gaze foveates the target 200 ms in advance of the contact. This strategy improves manual accuracy through visual feedback and the use of gaze-related signals to guide the hand/object...

  1. Active Collisions in Altered Gravity Reveal Eye-Hand Coordination Strategies: e44291

    National Research Council Canada - National Science Library

    Olivier White; Philippe Lefèvre; Alan M Wing; R Martyn Bracewell; Jean-Louis Thonnard

    2012-01-01

    .... Typically, gaze foveates the target 200 ms in advance of the contact. This strategy improves manual accuracy through visual feedback and the use of gaze-related signals to guide the hand/object...

  2. Detection, eye-hand coordination and virtual mobility performance in simulated vision for a cortical visual prosthesis device

    Science.gov (United States)

    Srivastava, Nishant R.; Troyk, Philip R.; Dagnelie, Gislin

    2009-06-01

    In order to assess visual performance using a future cortical prosthesis device, the ability of normally sighted and low vision subjects to adapt to a dotted 'phosphene' image was studied. Similar studies have been conduced in the past and adaptation to phosphene maps has been shown but the phosphene maps used have been square or hexagonal in pattern. The phosphene map implemented for this testing is what is expected from a cortical implantation of the arrays of intracortical electrodes, generating multiple phosphenes. The dotted image created depends upon the surgical location of electrodes decided for implantation and the expected cortical response. The subjects under tests were required to perform tasks requiring visual inspection, eye-hand coordination and way finding. The subjects did not have any tactile feedback and the visual information provided was live dotted images captured by a camera on a head-mounted low vision enhancing system and processed through a filter generating images similar to the images we expect the blind persons to perceive. The images were locked to the subject's gaze by means of video-based pupil tracking. In the detection and visual inspection task, the subject scanned a modified checkerboard and counted the number of square white fields on a square checkerboard, in the eye-hand coordination task, the subject placed black checkers on the white fields of the checkerboard, and in the way-finding task, the subjects maneuvered themselves through a virtual maze using a game controller. The accuracy and the time to complete the task were used as the measured outcome. As per the surgical studies by this research group, it might be possible to implant up to 650 electrodes; hence, 650 dots were used to create images and performance studied under 0% dropout (650 dots), 25% dropout (488 dots) and 50% dropout (325 dots) conditions. It was observed that all the subjects under test were able to learn the given tasks and showed improvement in

  3. Does an Eye-Hand Coordination Test Have Added Value as Part of Talent Identification in Table Tennis? : A Validity and Reproducibility Study

    NARCIS (Netherlands)

    Faber, IR (Irene); Nijhuis-van der Sanden, MWG (Ria); Oosterveld, FGJ (Frits)

    2014-01-01

    This study investigated the added value, i.e. discriminative and concurrent validity and reproducibility, of an eye-hand coordination test relevant to table tennis as part of talent identification. Forty-three table tennis players (7–12 years) from national (n = 13), regional (n = 11) and

  4. Does an eye-hand coordination test have added value as part of talent identification in table tennis? A validity and reproducibility study

    NARCIS (Netherlands)

    Faber, I.R.; Oosterveld, F.G.J.; Nijhuis-Van der Sanden, M.W.G.

    2014-01-01

    This study investigated the added value, i.e. discriminative and concurrent validity and reproducibility, of an eye-hand coordination test relevant to table tennis as part of talent identification. Forty-three table tennis players (7-12 years) from national (n = 13), regional (n = 11) and local

  5. Spatial Alignment of the Senses: The Role of Audition in Eye-Hand-Coordination

    Directory of Open Access Journals (Sweden)

    Thorsten Kluss

    2011-10-01

    Full Text Available Sensory modalities are usually appropriately aligned in space: audition, vision, and proprioception each direct actions to the same spatial coordinates. Subjects wearing prism glasses that shift the visual input first miss the target in a pointing task, but quickly adapt to the new sensorimotor configuration. This adaptation may take place either in the visual or the proprioceptive pathway, ie, the internal visual representation is shifted back or the proprioceptive one is shifted towards the new configuration. Usually, the proprioceptive component is affected, probably due to the often observed dominance of vision over other modalities. This process is changed when auditory stimuli are presented during prism exposure inducing a shift of the visual representation contrary to the aforementioned results, maybe because a cortical mechanism performs statistical reliability estimation: Both audition and proprioception remain unaffected by prism exposure and therefore force vision to realign. We investigated the influence of sound-source-location on prism-adaptation by assessing the effects of displaced (accordingly to the prism offset, centered and unlocalized sound-sources. We discuss the influence of spatial properties on sensory calibration, its implications on the notion of motor action as the binding element between senses and its role in spatial adaptation processes.

  6. Contribution of Leg Muscle Explosive Power and Eye-Hand Coordination to The Accuracy Smash of Athletes in Volleyball Club of Universitas Islam Riau

    Directory of Open Access Journals (Sweden)

    Mimi Yulianti

    2017-11-01

    Full Text Available The purpose of this study was to determine the contribution of leg muscle explosive power and eye-hand coordination. The type of research was correlational. The population in this study was all athletes who actively follow the training as many as 20 people and using total sampling technique. Thus the sample in this study amounted to 20 men athletes. The data were collected using the measurement test on the three variables: the leg muscle explosive power data was using vertical jump test, eyehand coordination was using ballwerfen und fangen test and smash accuracy was using smash accuracy test. The data were analyzed by product moment correlation and double correlation and then continued with contribution of the determinant formula. Based on data analysis found that there was contribution of leg muscle explosive power equal to 35,52%, eye-hand coordination equal to 20,79%, and both equal to 40,70% regarding to the accuracy smash of volleyball atletes of Universitas Islam Riau. It was concluded that there was contribution of leg muscle explosive power and eye-hand coordination to the smash accuracy of volleyball athlete of Universitas Islam Riau.

  7. Effects of conventional neurological treatment and a virtual reality training program on eye-hand coordination in children with cerebral palsy.

    Science.gov (United States)

    Shin, Ji-Won; Song, Gui-Bin; Hwangbo, Gak

    2015-07-01

    [Purpose] The purpose of the study was to evaluate the effects of conventional neurological treatment and a virtual reality training program on eye-hand coordination in children with cerebral palsy. [Subjects] Sixteen children (9 males, 7 females) with spastic diplegic cerebral palsy were recruited and randomly assigned to the conventional neurological physical therapy group (CG) and virtual reality training group (VRG). [Methods] Eight children in the control group performed 45 minutes of therapeutic exercise twice a week for eight weeks. In the experimental group, the other eight children performed 30 minutes of therapeutic exercise and 15 minutes of a training program using virtual reality twice a week during the experimental period. [Results] After eight weeks of the training program, there were significant differences in eye-hand coordination and visual motor speed in the comparison of the virtual reality training group with the conventional neurological physical therapy group. [Conclusion] We conclude that a well-designed training program using virtual reality can improve eye-hand coordination in children with cerebral palsy.

  8. Does an eye-hand coordination test have added value as part of talent identification in table tennis? A validity and reproducibility study.

    Directory of Open Access Journals (Sweden)

    Irene R Faber

    Full Text Available This study investigated the added value, i.e. discriminative and concurrent validity and reproducibility, of an eye-hand coordination test relevant to table tennis as part of talent identification. Forty-three table tennis players (7-12 years from national (n = 13, regional (n = 11 and local training centres (n = 19 participated. During the eye-hand coordination test, children needed to throw a ball against a vertical positioned table tennis table with one hand and to catch the ball correctly with the other hand as frequently as possible in 30 seconds. Four different test versions were assessed varying the distance to the table (1 or 2 meter and using a tennis or table tennis ball. 'Within session' reproducibility was estimated for the two attempts of the initial tests and ten youngsters were retested after 4 weeks to estimate 'between sessions' reproducibility. Validity analyses using age as covariate showed that players from the national and regional centres scored significantly higher than players from the local centre in all test versions (p<0.05. The tests at 1 meter demonstrated better discriminative ability than those at 2 meter. While all tests but one had a positive significant association with competition outcome, which were corrected for age influences, the version with a table tennis ball at 1 meter showed the highest association (r = 0.54; p = 0.001. Differences between the first and second attempts were comparable for all test versions (between -8 and +7 repetitions with ICC's ranging from 0.72 to 0.87. The smallest differences were found for the test with a table tennis ball at 1 meter (between -3 and +3 repetitions. Best test version as part of talent identification appears to be the version with a table tennis ball at 1 meter regarding the psychometric characteristics evaluated. Longitudinal studies are necessary to evaluate the predictive value of this test.

  9. THE INFLUENCE OF LEARNING APPROACH AND EYE-HAND COORDINATION AGAINST THE RESULTS OF A FREE THROW IN BASKETBALL GAMES "PENGARUH PENDEKATAN PEMBELAJARAN DAN KOORDINASI MATA-TANGAN TERHADAP HASIL FREE THROW PADA PERMAINAN BOLA BASKET"

    Directory of Open Access Journals (Sweden)

    Pramoda Wardana

    2017-06-01

    Full Text Available The purposes of this recearch were to examine the influence of direct and indirect learning approaches on free throw result in basketball, the difference of free throw result played by students with good and poor hand-eye coordinations, and the interaction influence of learning approach and hand-eye coordination on the result. This research applied experimental method with 2x2 factorial design. The population within this study was male students in 5th semester of the major program. Purposive Random Sampling was used as the sampling technique. 40 students were taken as the samples, in which students with good and poor hand-eye coordinations were equal. The analytical technique of this study belonged to ANOVA to use SPSS 22 and 5% significancy. Study result showed the difference of significant influence between direct and indirect learning approaches on free throw result, for p-value = 0,045, smaller than 0,05; the difference of increase in the result from students with good and poor hand-eye coordinations, for p-value = 0,035, smaller than 0,05; and the interaction of learning approach and hand-eye coordination on the result, for p-value = 0, 012, smaller than 0,05.It is concluded that there were differences of the significant influence between the learning approaches on free throw result, the free throw result from students with good and poor hand-eye coordinations, and there was an interaction influence of learning approaches and hand-eye coordination on the free throw result.

  10. Enhancing Eye-Hand Coordination with Therapy Intervention to Improve Visual-Spatial Abilities using ‘The Re-training Approach’ in Children with Down Syndrome: Three Case Studies

    Directory of Open Access Journals (Sweden)

    Deena Ashok

    2012-08-01

    Full Text Available Eye-hand coordination and visual-spatial abilities are an integral part of a child’s development, since both skills are necessary for functional independence as well as for academic progress.Purpose: This study is aimed at understanding the relationship between visual-spatial abilities and eye-hand coordination based on the ‘Re-training Approach’. An underlying assumption of this approach is that skills learned for one task can be generalised to other areas.Method: Three children with Down syndrome were initially tested for eye-hand coordination, and the tests were repeated periodically throughout the intervention programme which comprised visual-spatial activities.Results: The authors observed that there was a steady improvement in the eye-hand coordination as well as the visual-spatial abilities of children involved in the intensive therapy programme. This improvement manifested in the reduction of time taken to perform the coordination tests and in the errors made while performing the tests.doi 10.5463/DCID.v23i2.87

  11. Effects of Ving Tsun Chinese Martial Art Training on Upper Extremity Muscle Strength and Eye-Hand Coordination in Community-Dwelling Middle-Aged and Older Adults: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Shirley S. M. Fong

    2016-01-01

    Full Text Available Objectives. To evaluate the effects of Ving Tsun (VT martial art training on the upper extremity muscle strength and eye-hand coordination of middle-aged and older adults. Methods. This study used a nonequivalent pretest-posttest control group design. Forty-two community-dwelling healthy adults participated in the study; 24 (mean age ± SD = 68.5±6.7 years underwent VT training for 4 weeks (a supervised VT session twice a week, plus daily home practice, and 18 (mean age ± SD = 72.0±6.7 years received no VT training and acted as controls. Shoulder and elbow isometric muscle strength and eye-hand coordination were evaluated using the Lafayette Manual Muscle Test System and a computerized finger-pointing test, respectively. Results. Elbow extensor peak force increased by 13.9% (P=0.007 in the VT group and the time to reach peak force decreased (9.9% differentially in the VT group compared to the control group (P=0.033. For the eye-hand coordination assessment outcomes, reaction time increased by 2.9% in the VT group and decreased by 5.3% in the control group (P=0.002. Conclusions. Four weeks of VT training could improve elbow extensor isometric peak force and the time to reach peak force but not eye-hand coordination in community-dwelling middle-aged and older adults.

  12. Effects of Ving Tsun Chinese Martial Art Training on Upper Extremity Muscle Strength and Eye-Hand Coordination in Community-Dwelling Middle-Aged and Older Adults: A Pilot Study

    Science.gov (United States)

    Ng, Shamay S. M.; Cheng, Yoyo T. Y.; Yu, Esther Y. T.; Chow, Gary C. C.; Chak, Yvonne T. C.; Chan, Ivy K. Y.; Zhang, Joni; Macfarlane, Duncan

    2016-01-01

    Objectives. To evaluate the effects of Ving Tsun (VT) martial art training on the upper extremity muscle strength and eye-hand coordination of middle-aged and older adults. Methods. This study used a nonequivalent pretest-posttest control group design. Forty-two community-dwelling healthy adults participated in the study; 24 (mean age ± SD = 68.5 ± 6.7 years) underwent VT training for 4 weeks (a supervised VT session twice a week, plus daily home practice), and 18 (mean age ± SD = 72.0 ± 6.7 years) received no VT training and acted as controls. Shoulder and elbow isometric muscle strength and eye-hand coordination were evaluated using the Lafayette Manual Muscle Test System and a computerized finger-pointing test, respectively. Results. Elbow extensor peak force increased by 13.9% (P = 0.007) in the VT group and the time to reach peak force decreased (9.9%) differentially in the VT group compared to the control group (P = 0.033). For the eye-hand coordination assessment outcomes, reaction time increased by 2.9% in the VT group and decreased by 5.3% in the control group (P = 0.002). Conclusions. Four weeks of VT training could improve elbow extensor isometric peak force and the time to reach peak force but not eye-hand coordination in community-dwelling middle-aged and older adults. PMID:27525020

  13. A computationally efficient method for hand-eye calibration.

    Science.gov (United States)

    Zhang, Zhiqiang; Zhang, Lin; Yang, Guang-Zhong

    2017-07-19

    Surgical robots with cooperative control and semiautonomous features have shown increasing clinical potential, particularly for repetitive tasks under imaging and vision guidance. Effective performance of an autonomous task requires accurate hand-eye calibration so that the transformation between the robot coordinate frame and the camera coordinates is well defined. In practice, due to changes in surgical instruments, online hand-eye calibration must be performed regularly. In order to ensure seamless execution of the surgical procedure without affecting the normal surgical workflow, it is important to derive fast and efficient hand-eye calibration methods. We present a computationally efficient iterative method for hand-eye calibration. In this method, dual quaternion is introduced to represent the rigid transformation, and a two-step iterative method is proposed to recover the real and dual parts of the dual quaternion simultaneously, and thus the estimation of rotation and translation of the transformation. The proposed method was applied to determine the rigid transformation between the stereo laparoscope and the robot manipulator. Promising experimental and simulation results have shown significant convergence speed improvement to 3 iterations from larger than 30 with regard to standard optimization method, which illustrates the effectiveness and efficiency of the proposed method.

  14. Differences in Eye and Hand Movements of Novice and Experienced Press Operators.

    Science.gov (United States)

    Park, Kyung Soo; Kim, Yu Chang

    1997-01-01

    Presses are very widely used in industrial and commercial companies and are often the source of serious accidents occurring during operation. Most of the accidents are due to inadequate training of novice operators. Continuous recordings of eye and hand movements of five novice operators and five experienced operators in press operation were made. Significant difference between novice and experienced operators was observed in eye fixation time, eye movement patterns, hand dwell time, and eye-hand coordination. Also, differences were observed in spatial distribution of eye fixations during the die-closing portion of a stroke. There were no significant differences between novice and experienced operators in the eye and the hand movement time. The results could be used as basic data to establish a guide determining the method and training period to train novice operators.

  15. Visuomator transofrmations for eye-hand coordination

    NARCIS (Netherlands)

    Henriques, D.Y.P.; Medendorp, W.P.; Khan, A.Z.; Crawford, J.D.

    2002-01-01

    In recent years the scientific community has come to appreciate that the early cortical representations for visually guided arm movements are probably coded in a visual frame, i.e. relative to retinal landmarks. While this scheme accounts for many behavioral and neurophysiological observations, it

  16. Eye-Head Coordination for Visual Cognitive Processing

    Science.gov (United States)

    Fang, Yu; Nakashima, Ryoichi; Matsumiya, Kazumichi; Kuriki, Ichiro; Shioiri, Satoshi

    2015-01-01

    We investigated coordinated movements between the eyes and head (“eye-head coordination”) in relation to vision for action. Several studies have measured eye and head movements during a single gaze shift, focusing on the mechanisms of motor control during eye-head coordination. However, in everyday life, gaze shifts occur sequentially and are accompanied by movements of the head and body. Under such conditions, visual cognitive processing influences eye movements and might also influence eye-head coordination because sequential gaze shifts include cycles of visual processing (fixation) and data acquisition (gaze shifts). In the present study, we examined how the eyes and head move in coordination during visual search in a large visual field. Subjects moved their eyes, head, and body without restriction inside a 360° visual display system. We found patterns of eye-head coordination that differed those observed in single gaze-shift studies. First, we frequently observed multiple saccades during one continuous head movement, and the contribution of head movement to gaze shifts increased as the number of saccades increased. This relationship between head movements and sequential gaze shifts suggests eye-head coordination over several saccade-fixation sequences; this could be related to cognitive processing because saccade-fixation cycles are the result of visual cognitive processing. Second, distribution bias of eye position during gaze fixation was highly correlated with head orientation. The distribution peak of eye position was biased in the same direction as head orientation. This influence of head orientation suggests that eye-head coordination is involved in gaze fixation, when the visual system processes retinal information. This further supports the role of eye-head coordination in visual cognitive processing. PMID:25799510

  17. Changes in Timing and kinematics of goal directed eye-hand movements in early-stage Parkinson's disease

    NARCIS (Netherlands)

    B. Muilwijk (Bas); S. Verheij (Simone); J.J.M. Pel (Johan); A.J.W. Boon (Andrea); J. van der Steen (Hans)

    2013-01-01

    textabstractObjective: Many daily activities involve intrinsic or extrinsic goal-directed eye and hand movements. An extensive visuomotor coordination network including nigro-striatal pathways is required for efficient timing and positioning of eyes and hands. The aim of this study was to

  18. Saccades and reaches curve away from the other effector's target in simultaneous eye and hand movements.

    Science.gov (United States)

    Nissens, Tom; Fiehler, Katja

    2017-10-11

    Simultaneous eye and hand movements are highly coordinated and tightly coupled. This raises the question whether the selection of eye and hand targets relies on a shared attentional mechanism or separate attentional systems. Previous studies have revealed conflicting results by reporting evidence for both a shared as well as separate systems. Movement properties such as movement curvature can provide novel insights into this question as they provide a sensitive measure for attentional allocation during target selection. In the current study, participants performed simultaneous eye and hand movements to the same or different visual target locations. We show that both saccade and reaching movements curve away from the other effector's target location when they are simultaneously performed to spatially distinct locations. We argue that there is a shared attentional mechanism involved in selecting eye and hand targets which may be found on the level of effector independent priority maps. Copyright © 2017, Journal of Neurophysiology.

  19. Solving the robot-world, hand-eye(s) calibration problem with iterative methods

    Science.gov (United States)

    Robot-world, hand-eye calibration is the problem of determining the transformation between the robot end effector and a camera, as well as the transformation between the robot base and the world coordinate system. This relationship has been modeled as AX = ZB, where X and Z are unknown homogeneous ...

  20. Eye Control Deficits Coupled to Hand Control Deficits: Eye–Hand Incoordination in Chronic Cerebral Injury

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    John-Ross Rizzo

    2017-07-01

    Full Text Available It is widely accepted that cerebral pathology can impair ocular motor and manual motor control. This is true in indolent and chronic processes, such as neurodegeneration and in acute processes such as stroke or those secondary to neurotrauma. More recently, it has been suggested that disruptions in these control systems are useful markers for prognostication and longitudinal monitoring. The utility of examining the relationship or the coupling between these systems has yet to be determined. We measured eye and hand-movement control in chronic, middle cerebral artery stroke, relative to healthy controls, in saccade-to-reach paradigms to assess eye–hand coordination. Primary saccades were initiated significantly earlier by stroke participants relative to control participants. However, despite these extremely early initial saccades to the target, reaches were nevertheless initiated at approximately the same time as those of control participants. Control participants minimized the time period between primary saccade onset and reach initiation, demonstrating temporal coupling between eye and hand. In about 90% of all trials, control participants produced no secondary, or corrective, saccades, instead maintaining fixation in the terminal position of the primary saccade until the end of the reach. In contrast, participants with stroke increased the time period between primary saccade onset and reach initiation. During this temporal decoupling, multiple saccades were produced in about 50% of the trials with stroke participants making between one and five additional saccades. Reaches made by participants with stroke were both longer in duration and less accurate. In addition to these increases in spatial reach errors, there were significant increases in saccade endpoint errors. Overall, the magnitude of the endpoint errors for reaches and saccades were correlated across participants. These findings suggest that in individuals with otherwise intact

  1. Learning the optimal control of coordinated eye and head movements.

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    Sohrab Saeb

    2011-11-01

    Full Text Available Various optimality principles have been proposed to explain the characteristics of coordinated eye and head movements during visual orienting behavior. At the same time, researchers have suggested several neural models to underly the generation of saccades, but these do not include online learning as a mechanism of optimization. Here, we suggest an open-loop neural controller with a local adaptation mechanism that minimizes a proposed cost function. Simulations show that the characteristics of coordinated eye and head movements generated by this model match the experimental data in many aspects, including the relationship between amplitude, duration and peak velocity in head-restrained and the relative contribution of eye and head to the total gaze shift in head-free conditions. Our model is a first step towards bringing together an optimality principle and an incremental local learning mechanism into a unified control scheme for coordinated eye and head movements.

  2. [Bionic model for coordinated head-eye motion control].

    Science.gov (United States)

    Mao, Xiaobo; Chen, Tiejun

    2011-10-01

    The relationships between eye movements and head movements of the primate during gaze shifts are analyzed in detail in the present paper. Applying the mechanisms of neurophysiology to engineering domain, we have improved the robot eye-head coordination. A bionic control strategy of coordinated head-eye motion was proposed. The processes of gaze shifts are composed of an initial fast phase followed by a slow phase. In the fast phase saccade eye movements and slow head movements were combined, which cooperate to bring gaze from an initial resting position toward the new target rapidly, while in the slow phase the gaze stability and target fixation were ensured by the action of the vestibulo-ocular reflex (VOR) where the eyes and head rotate by equal amplitudes in opposite directions. A bionic gaze control model was given. The simulation results confirmed the effectiveness of the model by comparing with the results of neurophysiology experiments.

  3. Upper limb and eye movement coordination during reaching tasks in people with stroke.

    Science.gov (United States)

    Meadmore, Katie L; Exell, Timothy A; Burridge, Jane H; Hughes, Ann-Marie; Freeman, Christopher T; Benson, Valerie

    2017-06-09

    To enhance understanding of the relationship between upper limb and eye movements during reaching tasks in people with stroke. Eye movements were recorded from 10 control participants and 8 chronic stroke participants during a visual orienting task (Experiment 1) and a series of reaching tasks (Experiment 2). Stroke participants completed the reaching tasks using (i) their less impaired upper limb, (ii) their more impaired upper limb without support, and (iii) their more impaired upper limb, with support (SaeboMAS gravitational support and/or electrical stimulation). Participants were tested individually and completed both experiments in the same session. Oculomotor control and the coordination between the upper limb and the oculomotor system were found to be intact in stroke participants when no limb movements were required, or when the less impaired upper limb was used. However, when the more impaired upper limb was used, success and accuracy in reaching decreased and patterns of eye movements changed, with an observed increase in eye movements to the limb itself. With upper limb support, patterns of hand-eye coordination were found to more closely resemble those of the control group. Deficits in upper limb motor systems result in changes in patterns of eye movement behavior during reaching tasks. These changes in eye movement behavior can be modulated by providing upper limb support. Implications for Rehabilitation Deficits in upper limb motor systems can result in changes in patterns of eye movement behavior during reaching tasks. Upper limb support can reduce deficits in hand-eye coordination. Stroke rehabilitation outcomes should consider motor and oculomotor performance.

  4. Changes in Timing and kinematics of goal directed eye-hand movements in early-stage Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Muilwijk Danya

    2013-01-01

    Full Text Available Abstract Objective Many daily activities involve intrinsic or extrinsic goal-directed eye and hand movements. An extensive visuomotor coordination network including nigro-striatal pathways is required for efficient timing and positioning of eyes and hands. The aim of this study was to investigate how Parkinson’s disease (PD affects eye-hand coordination in tasks with different cognitive complexity. Methods We used a touch screen, an eye-tracking device and a motion capturing system to quantify changes in eye-hand coordination in early-stage PD patients (H&Y  Results In the pro-tapping task, saccade initiation towards extrinsic goals was not impaired. However, in the dual planning and anti-tapping task initiation of saccades towards intrinsic goals was faster in PD patients. Hand movements were differently affected: initiation of the hand movement was only delayed in the pro-tapping and dual planning task. Overall, hand movements in PD patients were slower executed compared to controls. Interpretation Whereas initiation of saccades in an extrinsic goal-directed task (pro-tapping task is not affected, early stage PD patients have difficulty in suppressing reflexive saccades towards extrinsic goals in tasks where the endpoint is an intrinsic goal (e.g. dual planning and anti-tapping task. This is specific for eye movements, as hand movements have delayed responses in the pro-tapping and dual planning task. This suggests that reported impairment of the dorsolateral prefrontal cortex in early-stage PD patients affects only inhibition of eye movements. We conclude that timing and kinematics of eye and hand movements in visuomotor tasks are affected in PD patients. This result may have clinical significance by providing a behavioral marker for the early diagnosis of PD.

  5. Intentional and attentional dynamics of speech-hand coordination.

    Science.gov (United States)

    Treffner, Paul; Peter, Mira

    2002-12-01

    Interest is rapidly growing in the hypothesis that natural language emerged from a more primitive set of linguistic acts based primarily on manual activity and hand gestures. Increasingly, researchers are investigating how hemispheric asymmetries are related to attentional and manual asymmetries (i.e., handedness). Both speech perception and production have origins in the dynamical generative movements of the vocal tract known as articulatory gestures. Thus, the notion of a "gesture" can be extended to both hand movements and speech articulation. The generative actions of the hands and vocal tract can therefore provide a basis for the (direct) perception of linguistic acts. Such gestures are best described using the methods of dynamical systems analysis since both perception and production can be described using the same commensurate language. Experiments were conducted using a phase transition paradigm to examine the coordination of speech-hand gestures in both left- and right-handed individuals. Results address coordination (in-phase vs. anti-phase), hand (left vs. right), lateralization (left vs. right hemisphere), focus of attention (speech vs. tapping), and how dynamical constraints provide a foundation for human communicative acts. Predictions from the asymmetric HKB equation confirm the attentional basis of functional asymmetry. Of significance is a new understanding of the role of perceived synchrony (p-centres) during intentional cases of gestural coordination. Copyright 2003 Elsevier Science B.V.

  6. Comparative eye-tracking evaluation of scatterplots and parallel coordinates

    Directory of Open Access Journals (Sweden)

    Rudolf Netzel

    2017-06-01

    Full Text Available We investigate task performance and reading characteristics for scatterplots (Cartesian coordinates and parallel coordinates. In a controlled eye-tracking study, we asked 24 participants to assess the relative distance of points in multidimensional space, depending on the diagram type (parallel coordinates or a horizontal collection of scatterplots, the number of data dimensions (2, 4, 6, or 8, and the relative distance between points (15%, 20%, or 25%. For a given reference point and two target points, we instructed participants to choose the target point that was closer to the reference point in multidimensional space. We present a visual scanning model that describes different strategies to solve this retrieval task for both diagram types, and propose corresponding hypotheses that we test using task completion time, accuracy, and gaze positions as dependent variables. Our results show that scatterplots outperform parallel coordinates significantly in 2 dimensions, however, the task was solved more quickly and more accurately with parallel coordinates in 8 dimensions. The eye-tracking data further shows significant differences between Cartesian and parallel coordinates, as well as between different numbers of dimensions. For parallel coordinates, there is a clear trend toward shorter fixations and longer saccades with increasing number of dimensions. Using an area-of-interest (AOI based approach, we identify different reading strategies for each diagram type: For parallel coordinates, the participants’ gaze frequently jumped back and forth between pairs of axes, while axes were rarely focused on when viewing Cartesian coordinates. We further found that participants’ attention is biased: toward the center of the whole plotfor parallel coordinates and skewed to the center/left side for Cartesian coordinates. We anticipate that these results may support the design of more effective visualizations for multidimensional data.

  7. Processing coordinate structures in Chinese: evidence from eye movements.

    Directory of Open Access Journals (Sweden)

    Chen Qingrong

    Full Text Available This article reports the results of an eye-tracking experiment that investigated the processing of coordinate structures in Chinese sentence comprehension. The study tracked the eye movements of native Chinese readers as they read sentences consisting of two independent clauses connected by the word huo zhe. The data strongly confirmed readers' preference for an initial noun phrase (NP-coordination parsing in Chinese coordination structure. When huo zhe was absent from the beginning of a sentence, we identified a cost associated with abandoning the NP-coordination analysis, which was evident with regard to the second NP when the coordination was unambiguous. Otherwise, this cost was evident with regard to the verb, the syntactically disambiguating region, when the coordination was ambiguous. However, the presence of a sentence-initial huo zhe reduced reading times and regressions in the huo zhe NP and the verb regions. We believe that the word huo zhe at the beginning of a sentence helps the reader predict that the sentence contains a parallel structure. Before the corresponding phrases appear, the readers can use the word huo zhe and the language structure thereafter to predicatively construct the syntactic structure. Such predictive capability can eliminate the reader's preference for NP-coordination analysis. Implications for top-down parsing theory and models of initial syntactic analysis and reanalysis are discussed.

  8. Hand preferences for bimanual coordination in 29 bonobos (Pan paniscus).

    Science.gov (United States)

    Chapelain, Amandine S; Hogervorst, Eef

    2009-01-03

    Brain lateralization has long been thought to be unique to humans. To investigate the origins and functions of this feature, researchers study behavioural laterality in other animals. Despite a substantial database, manual laterality in non-human primates remains a controversial topic. We give here a review of the main findings on manual preference in great apes. This article presents data on hand preferences for a bimanual coordination in 29 bonobos (Pan paniscus). The study aims to provide data on manual laterality for a complex bimanual task in this very interesting and rarely studied species. Hand preferences were assessed using the 'tube task'. This task has been used with other species, which allows reliable data comparisons. The task requires a bimanual coordinated precise action: the subject holds the tube with one hand while reaching for food inside with the other hand. As a complex task, this measure has been shown to be efficient in revealing hand preferences. It has revealed group-level right bias in chimpanzees. Bonobos had never been tested. We recorded both independent bouts (counting only the first pattern of a sequence of identical actions) and frequency (counting every action). The bonobos exhibited strong hand preferences. With frequency, 11 bonobos were classified as right-handed, 15 were left-handed and 3 had no preference. With bouts, 8 bonobos were right-handed, 9 were left-handed and 12 had no preference. No group-level bias appeared. The results are discussed in relation with previous findings and theories on brain lateralization.

  9. Following and intercepting scribbles: interactions between eye and hand control.

    Science.gov (United States)

    Mrotek, Leigh A

    2013-06-01

    The smooth pursuit eye movement system appears to be importantly engaged during the planning and execution of interceptive hand movements. The present study sought to probe the interaction between eye and hand control systems by examining their responses during an interception task that included target speed perturbations. On 2/3 of trials, the target increased or decreased speed at various times, ranging from about 300 ms before to 150 ms after the onset of a finger movement directed to intercept the target and was triggered by a GO signal. Additionally, the same 2D sum-of-sines target trajectories were followed with the eyes without interception. The smooth pursuit system responded more quickly if the target speed perturbation occurred earlier during the reaction time (i.e., near the time of the GO signal). Similarly, the finger movement began more quickly if target speed was increased earlier during the reaction time. For early perturbation conditions, the initial direction of the finger movement matched the predicted target intercept using the new target speed. For perturbations occurring after finger movement, onset initial direction of finger movement did not match target interception such that the finger path began to curve toward the perturbed target after about 150-200 ms. The results support the idea of an active process of visual target path extrapolation simultaneously used to guide both the eye and hand.

  10. Eye tracking a self-moved target with complex hand-target dynamics.

    Science.gov (United States)

    Landelle, Caroline; Montagnini, Anna; Madelain, Laurent; Danion, Frederic

    2016-10-01

    Previous work has shown that the ability to track with the eye a moving target is substantially improved when the target is self-moved by the subject's hand compared with when being externally moved. Here, we explored a situation in which the mapping between hand movement and target motion was perturbed by simulating an elastic relationship between the hand and target. Our objective was to determine whether the predictive mechanisms driving eye-hand coordination could be updated to accommodate this complex hand-target dynamics. To fully appreciate the behavioral effects of this perturbation, we compared eye tracking performance when self-moving a target with a rigid mapping (simple) and a spring mapping as well as when the subject tracked target trajectories that he/she had previously generated when using the rigid or spring mapping. Concerning the rigid mapping, our results confirmed that smooth pursuit was more accurate when the target was self-moved than externally moved. In contrast, with the spring mapping, eye tracking had initially similar low spatial accuracy (though shorter temporal lag) in the self versus externally moved conditions. However, within ∼5 min of practice, smooth pursuit improved in the self-moved spring condition, up to a level similar to the self-moved rigid condition. Subsequently, when the mapping unexpectedly switched from spring to rigid, the eye initially followed the expected target trajectory and not the real one, thereby suggesting that subjects used an internal representation of the new hand-target dynamics. Overall, these results emphasize the stunning adaptability of smooth pursuit when self-maneuvering objects with complex dynamics. Copyright © 2016 the American Physiological Society.

  11. Hands Coordination in Data Entry with a Two-Hand Chord Typewriter.

    Science.gov (United States)

    1983-06-01

    keyboard , are the achievement of several months of daily practice (e.g., Hill, Rejall, & Thorndike, 1913; Dvorak , Merrick, Dealey, & Ford, 1936; Gentner...transcription skills, typing behavior, two-hand coordination, perceptual-motor skills, motor behavior, chord keyboards 20. ABSTRACT (Continue on reverse...acquisition and operation of a data entry skill based upon a newly designee two-hand chord keyboard . This keyboard represents an effort to identify effective

  12. Hand-eye calibration using a target registration error model.

    Science.gov (United States)

    Chen, Elvis C S; Morgan, Isabella; Jayarathne, Uditha; Ma, Burton; Peters, Terry M

    2017-10-01

    Surgical cameras are prevalent in modern operating theatres and are often used as a surrogate for direct vision. Visualisation techniques (e.g. image fusion) made possible by tracking the camera require accurate hand-eye calibration between the camera and the tracking system. The authors introduce the concept of 'guided hand-eye calibration', where calibration measurements are facilitated by a target registration error (TRE) model. They formulate hand-eye calibration as a registration problem between homologous point-line pairs. For each measurement, the position of a monochromatic ball-tip stylus (a point) and its projection onto the image (a line) is recorded, and the TRE of the resulting calibration is predicted using a TRE model. The TRE model is then used to guide the placement of the calibration tool, so that the subsequent measurement minimises the predicted TRE. Assessing TRE after each measurement produces accurate calibration using a minimal number of measurements. As a proof of principle, they evaluated guided calibration using a webcam and an endoscopic camera. Their endoscopic camera results suggest that millimetre TRE is achievable when at least 15 measurements are acquired with the tracker sensor ∼80 cm away on the laparoscope handle for a target ∼20 cm away from the camera.

  13. Relationship between eye preference and binocular rivalry, and between eye-hand preference and reading ability in children.

    Science.gov (United States)

    Fagard, J; Monzalvo-Lopez, K; Mamassian, P

    2008-12-01

    One goal of the experiment presented here was to check, in children, the relationship between eye preference when sighting at different angles and eye dominance in binocular rivalry. In addition, since it is sometimes argued that a crossed pattern of eye-hand preference might put children at risk of difficulties in learning to read, we evaluated the relationship between this pattern and reading achievement in first and sixth graders. Results showed that a majority of children are right-eyed for monosighting, and that intrinsic preference and spatial factor influence the choice of eye. As many children were right- or left-eye dominant, and eye dominance was not related to eye preference. We found no relationship between eye-hand preference and reading proficiency, thus not confirming that a crossed pattern of eye-hand preference might put children at risk of difficulties in learning to read. Consistent handers were more advanced in reading than inconsistent handers.

  14. Effects of eye dominance (left vs. right) and cannabis use on intermanual coordination and negative symptoms in schizophrenia patients.

    Science.gov (United States)

    Gorynia, Inge; Schwaiger, Markus; Heinz, Andreas

    2014-12-01

    Based on the previous findings, it has been assumed that in schizophrenia patients, eye dominance and cannabis use will affect negative symptoms and intermanual coordination (IMC), an index of interhemispheric communication. But eye dominance, specifically the clinical findings for it, has been neglected in schizophrenia research. We therefore investigated its effects in 52 right-handed (36 right-eyed and 16 left-eyed) and 51 left-handed (35 left-eyed and 16 right-eyed) schizophrenia in-patients without and with drug use. Eye dominance affected IMC in all schizophrenia patients. When comparing right- and left-handers, we found that this result was only significant in the right-handed patients and in the smaller subgroup without drug use. In the right-handers, left eye dominance-like left-handedness-was associated with higher values in IMC and less pronounced manifestation of negative symptoms, right eye dominance was not. Thus, left-eyed right-handers may be more closely related to left-handers than to right-handers. In accordance with the results from the literature, we suggest that these findings are due to better interhemispheric connections and less impairment of white matter structures, especially in right-hemispheric regions. Moreover, cannabis use was related to higher scores in IMC and less pronounced negative symptoms, but only in the right-eyed and not in the left-eyed right-handers or in the left-handers. Hence, differences in eye dominance and handedness may be partially responsible for different results in interhemispheric connections among cannabis users. In conclusion, both eye dominance and use of cannabis should be taken into account when assessing clinical symptoms in schizophrenia patients.

  15. Eye and hand movements during reconstruction of spatial memory.

    Science.gov (United States)

    Burke, Melanie R; Allen, Richard J; Gonzalez, Claudia

    2012-01-01

    Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (e.g., Awh et al, 2006 Neuroscience 139 201-208). This study explored the role of spatial attention and visual search in an adapted Corsi spatial memory task. Eye movements and touch responses were recorded from participants who recalled locations (signalled by colour or shape change) from an array presented either simultaneously or sequentially. The time delay between target presentation and recall (0, 5, or 10 s) and the number of locations to be remembered (2-5) were also manipulated. Analysis of the response phase revealed subjects were less accurate (touch data) and fixated longer (eye data) when responding to sequentially presented targets suggesting higher cognitive effort. Fixation duration on target at recall was also influenced by whether spatial location was initially signalled by colour or shape change. Finally, we found that the sequence tasks encouraged longer fixations on the signalled targets than simultaneous viewing during encoding, but no difference was observed during recall. We conclude that the attentional manipulations (colour/shape) mainly affected the eye movement parameters, whereas the memory manipulation (sequential versus simultaneous, number of items) mainly affected the performance of the hand during recall, and thus the latter is more important for ascertaining if an item is remembered or forgotten. In summary, the nature of the stimuli that is used and how it is presented play key roles in determining subject performance and behaviour during spatial memory tasks.

  16. Kinematic property of target motion conditions gaze behavior and eye-hand synergy during manual tracking.

    Science.gov (United States)

    Huang, Chien-Ting; Hwang, Ing-Shiou

    2013-12-01

    This study investigated how frequency demand and motion feedback influenced composite ocular movements and eye-hand synergy during manual tracking. Fourteen volunteers conducted slow and fast force-tracking in which targets were displayed in either line-mode or wave-mode to guide manual tracking with target movement of direct position or velocity nature. The results showed that eye-hand synergy was a selective response of spatiotemporal coupling conditional on target rate and feedback mode. Slow and line-mode tracking exhibited stronger eye-hand coupling than fast and wave-mode tracking. Both eye movement and manual action led the target signal during fast-tracking, while the latency of ocular navigation during slow-tracking depended on the feedback mode. Slow-tracking resulted in more saccadic responses and larger pursuit gains than fast-tracking. Line-mode tracking led to larger pursuit gains but fewer and shorter gaze fixations than wave-mode tracking. During slow-tracking, incidences of saccade and gaze fixation fluctuated across a target cycle, peaking at velocity maximum and the maximal curvature of target displacement, respectively. For line-mode tracking, the incidence of smooth pursuit was phase-dependent, peaking at velocity maximum as well. Manual behavior of slow or line-mode tracking was better predicted by composite eye movements than that of fast or wave-mode tracking. In conclusion, manual tracking relied on versatile visual strategies to perceive target movements of different kinematic properties, which suggested a flexible coordinative control for the ocular and manual sensorimotor systems. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Different spatial representations guide eye and hand movements.

    Science.gov (United States)

    Lisi, Matteo; Cavanagh, Patrick

    2017-02-01

    Our visual system allows us to localize objects in the world and plan motor actions toward them. We have recently shown that the localization of moving objects differs between perception and saccadic eye movements (Lisi & Cavanagh, 2015), suggesting different localization mechanisms for perception and action. This finding, however, could reflect a unique feature of the saccade system rather than a general dissociation between perception and action. To disentangle these hypotheses, we compared object localization between saccades and hand movements. We flashed brief targets on top of double-drift stimuli (moving Gabors with the internal pattern drifting orthogonally to their displacement, inducing large distortions in perceived location and direction) and asked participants to point or make saccades to them. We found a surprising difference between the two types of movements: Although saccades targeted the physical location of the flashes, pointing movements were strongly biased toward the perceived location (about 63% of the perceptual illusion). The same bias was found when pointing movements were made in open-loop conditions (without vision of the hand). These results indicate that dissociations are present between different types of actions (not only between action and perception) and that visual processing for saccadic eye movements differs from that for other actions. Because the position bias in the double-drift stimulus depends on a persisting influence of past sensory signals, we suggest that spatial maps for saccades might reflect only recent, short-lived signals, and the spatial representations supporting conscious perception and hand movements integrate visual input over longer temporal intervals.

  18. Intentional switches between bimanual coordination patterns are primarily effectuated by the nondominant hand

    NARCIS (Netherlands)

    de Poel, HJ; Peper, CE; Beek, PJ

    Based on indications that hand dominance is characterized by asymmetrical interlimb coupling strength (with the dominant hand exerting stronger influences on the nondominant hand than vice versa), intentional switches between rhythmic bimanual coordination patterns were predicted to be mediated

  19. Virtual reality glasses and "Eye-hands blind technique" for microsurgical training in Neurosurgery.

    Science.gov (United States)

    Choque-Velasquez, Joham; Colasanti, Roberto; Collan, Juhani; Kinnunen, Riina; Jahromi, Behnam Rezai; Hernesniemi, Juha

    2018-01-19

    Microsurgical skills and eye-hand coordination need a continuous training to be developed and refined. However, well-equipped microsurgical laboratories are not so widespread as their setting-up is very expensive. Herein, we present a novel microsurgical training system which requires a high-resolution personal computer screen, smartphones and virtual reality glasses. A smartphone, which is placed on a holder at a height of about 15-20 cm from the surgical target field, is used as the webcam of the computer. A specific software is used to duplicate the video camera image. The video may be transferred from the computer to another smartphone which may be connected to virtual reality glasses. Using the above described training model, we progressively performed more and more complex microsurgical exercises. It did not take long to set up our system thus saving time for the training sessions. Our proposed training model may represent a very affordable and efficient system to improve eye-hand coordination and dexterity in using not only the operating microscope, but also endoscopes and exoscopes. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Automated cross-modal mapping in robotic eye/hand systems using plastic radial basis function networks

    Science.gov (United States)

    Meng, Qinggang; Lee, M. H.

    2007-03-01

    Advanced autonomous artificial systems will need incremental learning and adaptive abilities similar to those seen in humans. Knowledge from biology, psychology and neuroscience is now inspiring new approaches for systems that have sensory-motor capabilities and operate in complex environments. Eye/hand coordination is an important cross-modal cognitive function, and is also typical of many of the other coordinations that must be involved in the control and operation of embodied intelligent systems. This paper examines a biologically inspired approach for incrementally constructing compact mapping networks for eye/hand coordination. We present a simplified node-decoupled extended Kalman filter for radial basis function networks, and compare this with other learning algorithms. An experimental system consisting of a robot arm and a pan-and-tilt head with a colour camera is used to produce results and test the algorithms in this paper. We also present three approaches for adapting to structural changes during eye/hand coordination tasks, and the robustness of the algorithms under noise are investigated. The learning and adaptation approaches in this paper have similarities with current ideas about neural growth in the brains of humans and animals during tool-use, and infants during early cognitive development.

  1. The Intersection between Ocular and Manual Motor Control: Eye–Hand Coordination in Acquired Brain Injury

    Directory of Open Access Journals (Sweden)

    John-Ross Rizzo

    2017-06-01

    Full Text Available Acute and chronic disease processes that lead to cerebral injury can often be clinically challenging diagnostically, prognostically, and therapeutically. Neurodegenerative processes are one such elusive diagnostic group, given their often diffuse and indolent nature, creating difficulties in pinpointing specific structural abnormalities that relate to functional limitations. A number of studies in recent years have focused on eye–hand coordination (EHC in the setting of acquired brain injury (ABI, highlighting the important set of interconnected functions of the eye and hand and their relevance in neurological conditions. These experiments, which have concentrated on focal lesion-based models, have significantly improved our understanding of neurophysiology and underscored the sensitivity of biomarkers in acute and chronic neurological disease processes, especially when such biomarkers are combined synergistically. To better understand EHC and its connection with ABI, there is a need to clarify its definition and to delineate its neuroanatomical and computational underpinnings. Successful EHC relies on the complex feedback- and prediction-mediated relationship between the visual, ocular motor, and manual motor systems and takes advantage of finely orchestrated synergies between these systems in both the spatial and temporal domains. Interactions of this type are representative of functional sensorimotor control, and their disruption constitutes one of the most frequent deficits secondary to brain injury. The present review describes the visually mediated planning and control of eye movements, hand movements, and their coordination, with a particular focus on deficits that occur following neurovascular, neurotraumatic, and neurodegenerative conditions. Following this review, we also discuss potential future research directions, highlighting objective EHC as a sensitive biomarker complement within acute and chronic neurological disease processes.

  2. Thinking with your eye, thinking with your hand

    Directory of Open Access Journals (Sweden)

    Juan Manuel Sánchez de la Chica

    2013-10-01

    Full Text Available AbstractDefining architecture as visual-functional art, Asis Cabrero goes back to the origins of the human species to explain the elements of conscience involved in the work of humankind. Human survival is voluntary, variable, personal and inventive in sharp contrast with the instinct of nature's other species. Humans are intelligent beings whose thinking is determined by their sense of sight, by the ability of their hands to make tools, on top of their predatory nature. This human animal of exchangeable organs is able to specialize himself in the use of tools he makes to be on equal terms with specialized animals. So does man make tools to come face to face with a variable and changing nature, be it a knife, an ax or a shelter.Since Architecture is a product of what your eye sees, it is the functional use of your hand that comes into play in Architectural drawings. According to Cabrero, matter becomes material through tools, to be rigged, to be built. Tools which have evolved over the course of history as matter always remain unchanged in nature. Asís Cabrero has researched five primitive architectures related to five original matters. He has studied the dome structure, the lintel, the framework, the laminated structure and the removable structure in connection with the rational use of clay, stone, wood, branches and skin.The variety of available materials in the professional career of Asís Cabrero, from post-war isolation to the liberalization of the sixties, allow us to set five ages in the work of Francisco de Asís Cabrero according to the material and the tools he uses.Key wordsFrancisco Cabrero, architecture, instruments, material, structure, tools

  3. Parameterizations for reducing camera reprojection error for robot-world hand-eye calibration

    Science.gov (United States)

    Accurate robot-world, hand-eye calibration is crucial to automation tasks. In this paper, we discuss the robot-world, hand-eye calibration problem which has been modeled as the linear relationship AX equals ZB, where X and Z are the unknown calibration matrices composed of rotation and translation ...

  4. Cognitive Control of Saccadic Eye Movements in Children with Developmental Coordination Disorder.

    Directory of Open Access Journals (Sweden)

    Claudia C Gonzalez

    Full Text Available The ability to use advance information to prepare and execute a movement requires cognitive control of behaviour (e.g., anticipation and inhibition. Our aim was to explore the integrity of saccadic eye movement control in developmental coordination disorder (DCD and typically developing (TD children (8-12 years and assess how these children plan and inhibit saccadic responses, the principal mechanisms within visual attention control. Eye movements and touch responses were measured (separately and concurrently in Cued and Non-Cued conditions. We found that children with DCD had similar saccade kinematics to the TD group during saccade initiation. Advance information decreased hand movement duration in both groups during Cued trials, but decrements in accuracy were significantly worse in the DCD group. In addition, children with DCD exhibited greater inhibitory errors and inaccurate fixation during the Cued trials. Thus, children with DCD were reasonably proficient in executing saccades during reflexive (Non-Cued conditions, but showed deficits in more complex control processes involving prediction and inhibition. These findings have implications for our understanding of motor control in children with DCD.

  5. Effects of an Occupational Therapy Hand Dominance Transfer Intervention for Soldiers With Crossed Hand-Eye Dominance.

    Science.gov (United States)

    Luken, Michelle; Yancosek, Kathleen E

    2017-01-01

    Crossed dominance (CD) is defined as an individual's dominant hand and dominant eye being on opposite sides of the body. CD negatively impacts an individual's ability to accurately aim and fire long-barreled guns. The authors developed and evaluated a hand dominance transfer (HDT) intervention to improve the M16 rifle shooting accuracy, efficiency, and skill transfer. Twenty-four U.S. Army soldiers with CD were taught how to handle and fire an M16 rifle using the nondominant hand. Training was conducted at a military, indoor laser-equipped weapons simulator. Accuracy for shooting 40 rounds at baseline with the nondominant eye and dominant hand (NDE/DH) was 22.12 compared to shooting 30.46 with the dominant eye and nondominant hand (DE/NDH). This difference was statistically significant with p = .000. The transfer of shooting accuracy skill (retention) following the HDT intervention was 33.42 with a comparative p value of .100. Efficiency of shooting 10 rounds at baseline with the NDE/DH was 6.3 compared to shooting 7.3 with the DE/NDH. This difference was not statistically significant (p = .107). The transfer of shooting efficiency skill (retention) was 7.96 with a comparative p value of .349. This study supports shooting with the DE/NDH. HDT could be further developed to address the soldiering skill of shooting an M16.

  6. Hand preferences for coordinated bimanual actions in 777 great apes

    DEFF Research Database (Denmark)

    Hopkins, William D; Phillips, Kimberley A; Bania, Amanda

    2011-01-01

    Whether or not nonhuman primates exhibit population-level handedness remains a topic of considerable scientific debate. Here, we examined handedness for coordinated bimanual actions in a sample of 777 great apes including chimpanzees, bonobos, gorillas, and orangutans. We found population...... among species as a result of ecological adaptations associated with posture and locomotion. We further suggest that historical views of nonhuman primate handedness have been too anthropocentric, and we advocate for a larger evolutionary framework for the consideration of handedness and other aspects...... of hemispheric specialization among primates....

  7. Goal-directed arm movements change eye-head coordination

    NARCIS (Netherlands)

    Smeets, Jeroen B J; Hayhoe, Mary M.; Ballard, Dana H.

    1996-01-01

    We compared the head movements accompanying gaze shifts while our subjects executed different manual operations, requiring gaze shifts of about 30°. The different tasks yielded different latencies between gaze shifts and hand movements, and different maximum velocities of the hand. These changes in

  8. Complete calibration of the autonomous hand-eye robot JANUS

    OpenAIRE

    Garcia, C.

    1998-01-01

    The current prototype of the JANUS robot consists of two arms and a neck with two mounted color cameras. Calibrating JANUS means to find the geometric relationships between each of these components and the reference coordinate system of the robot. The calibration procedure that we present in this report is completely vision-based: the relationships between each camera and the neck and between each arm and the neck are determined using visual measurements, which leads to a low-cost and automat...

  9. The Effect of Intensive Bimanual Training on Coordination of the Hands in Children with Congenital Hemiplegia

    Science.gov (United States)

    Hung, Ya-Ching; Casertano, Lorenzo; Hillman, Andrew; Gordon, Andrew M.

    2011-01-01

    Recent studies have suggested efficacy of intensive bimanual training in improving the quality and quantity of affected hand use in children with hemiplegia. However, it is not known whether such training affects the coordination of the two hands. In the present study, 20 children with congenital hemiplegia (age 4-10 years; MACS levels I-II) were…

  10. Abnormalities of Eye–Hand Coordination in Patients with Writer's Cramp: Possible Role of the Cerebellum

    Directory of Open Access Journals (Sweden)

    Ketan Jhunjhunwala

    2017-10-01

    Full Text Available Background: Writer’s cramp (WC is one of the commonly observed focal dystonias. The pathophysiology of WC has not been fully understood. The role of the cerebellum has been increasingly recognized in the pathogenesis of dystonia. As the cerebellum is crucial for maintaining accurate eye–hand coordination (EHC, its role in the pathogenesis of WC can be investigated by studying the EHC in patients with WC.Methods: Fifteen patients with WC (women:men, 3:12 and 15 age- and gender-matched controls performed oculomotor and EHC tasks. A visually guided stimulus (VGS task was first performed with eye-only condition (EOC and then with EHC.Results: A significant interaction between the groups (controls and patients and tasks (EOC and EHC with age as a covariate confirmed that the two groups reacted differently to the tasks in saccadic latency (F(1,27 = 4.8; p = 0.039 and average saccade acceleration (F(1,27 = 10.6; p = 0.003. The curvature index of acceleration of the hand was significantly more in patients compared to controls (patients vs. controls, 2.4±0.4 vs. 1.8±0.2, p = 0.01. While performing the EHC task, there was a significant correlation of the Writer’s Cramp Rating Score with the average saccadic speed (–0.61, p = 0.016, peak saccadic deceleration (0.59, p = 0.019 and average saccadic acceleration (–0.63, p = 0.012.Discussion: Saccadic acceleration and latency are abnormal while performing EHC tasks in patients with WC. Our study gives further insights into the possible role of the cerebellum in the pathogenesis of WC.

  11. Eye and Hand Movements during Reconstruction of Spatial Memory

    Directory of Open Access Journals (Sweden)

    Melanie Rose Burke

    2012-05-01

    Full Text Available Recent behavioural and biological evidence indicates common mechanisms serving working memory and attention (eg, Awh et al 2006, Trends in Cognitive Sciences 10, 124–130. This study explored the role of spatial attention and visual search in an adapted Corsi spatial memory task. Eye movements and touch responses were recorded from participants who recalled locations (signalled by colour or shape change from an array presented either simultaneously or sequentially. The time delay between target presentation and recall (0, 5, or 10s and the number of locations to be remembered (2–5 were also manipulated. Analysis of the response phase revealed subjects were less accurate (touch data and fixated longer (eye data when responding to sequentially presented targets. Fixation duration was also influenced by whether spatial location was initially signalled by colour or shape change. We conclude that attention and temporal delays during retention of a target play a minor role in motor behaviour during a corsi spatial memory task. In contrast, the type of memory required (ie, location and/or memory and number of items plays a key role on subject performance and behaviour.

  12. Thinking with your eye, thinking with your hand

    OpenAIRE

    Juan Manuel Sánchez de la Chica

    2013-01-01

    AbstractDefining architecture as visual-functional art, Asis Cabrero goes back to the origins of the human species to explain the elements of conscience involved in the work of humankind. Human survival is voluntary, variable, personal and inventive in sharp contrast with the instinct of nature's other species. Humans are intelligent beings whose thinking is determined by their sense of sight, by the ability of their hands to make tools, on top of their predatory nature. This human animal of ...

  13. Impairment of online control of hand and eye movements in a monkey model of optic ataxia.

    Science.gov (United States)

    Battaglia-Mayer, Alexandra; Ferrari-Toniolo, Simone; Visco-Comandini, Federica; Archambault, Philippe S; Saberi-Moghadam, Sohrab; Caminiti, Roberto

    2013-11-01

    The parietal mechanisms for online control of hand trajectory were studied by combining single-cell recording and reversible inactivation of superior parietal area 5 (PE/PEc; SPL) of monkeys while these made reaches and saccades to visual targets, when the target position changed unexpectedly. Neural activity was modulated by hand position, speed, and movement direction, and by pre- and/or postsaccadic signals. After bilateral muscimol injection, an increase in the hand reaction- and movement-time toward both the first and second targets was observed. This caused an increase in the time necessary for the trajectory correction, and therefore an elongation of the hand-path toward the first target location. Furthermore, hand trajectories were different in shape than control ones. An elongation of the eye reaction time to both first and second targets was also observed, which could partially explain the deficit of planning and correction of hand movement. These results identify the superior parietal lobule as a crucial node in the online control of hand and eye movement and highlight the role of the eye impairment in the emergence of the reaching disorder so far regarded as the hallmark of optic ataxia.

  14. Eye movements show similar adaptations in temporal coordination to movement planning conditions in both people with and without cerebral palsy.

    Science.gov (United States)

    Payne, Alexander R; Plimmer, Beryl; McDaid, Andrew; Davies, T Claire

    2017-05-01

    The effects of cerebral palsy on movement planning for simple reaching tasks are not well understood. Movement planning is complex and entails many processes which could be affected. This study specifically sought to evaluate integrating task information, decoupling movements, and adjusting to altered mapping. For a reaching task, the asynchrony between the eye onset and the hand onset was measured across different movement planning conditions for participants with and without cerebral palsy. Previous research shows people without cerebral palsy vary this temporal coordination for different planning conditions. Our measurements show similar adaptations in temporal coordination for groups with and without cerebral palsy, to three of the four variations in planning condition tested. However, movement durations were still longer for the participants with cerebral palsy. Hence for simple goal-directed reaching, movement execution problems appear to limit activity more than movement planning deficits.

  15. Hand-Eye Calibration and Inverse Kinematics of Robot Arm using Neural Network

    DEFF Research Database (Denmark)

    Wu, Haiyan; Tizzano, Walter; Andersen, Thomas Timm

    2013-01-01

    tasks. This paper describes the theory and implementation of neural networks for hand-eye calibration and inverse kinematics of a six degrees of freedom robot arm equipped with a stereo vision system. The feedforward neural network and the network training with error propagation algorithm are applied...

  16. DISABILITIES OF HANDS, FEET AND EYES IN NEWLY-DIAGNOSED LEPROSY PATIENTS IN EASTERN NEPAL

    NARCIS (Netherlands)

    SCHIPPER, A; LUBBERS, WJ; HOGEWEG, M; DESOLDENHOFF, R

    The objective of the study was to determine the magnitude of hand/feet/eye disabilities in newly diagnosed leprosy patients by examining all newly diagnosed leprosy patients who presented at the Eastern Leprosy Control Project (supported by The Netherlands Leprosy Relief Association), made up of a

  17. Effect of hand paddles and parachute on backstroke coordination and stroke parameters.

    Science.gov (United States)

    Telles, Thiago; Barroso, Renato; Figueiredo, Pedro; Salgueiro, Diego Fortes de Souza; Vilas-Boas, João Paulo; Junior, Orival Andries

    2017-05-01

    Hand paddles and parachutes have been used in order to overload swimmers, and consequently increase the propulsive force generation in swimming. However, their use may affect not only kinematical parameters (average speed, stroke length and stroke rate), but also time gaps between propulsive phases, assessed through the index of coordination (IdC). The objective of this study was to assess the effects of hand paddles and parachute use, isolated or combined, on kinematical parameters and coordination. Eleven swimmers (backstroke 50-m time: 29.16 ± 1.43 s) performed four 15-m trials in a randomised order at maximal intensity: (1) without implements (FREE), (2) with hand paddles (HPD), (3) with parachute (PCH) and (4) with hand paddles plus parachute (HPD+PCH). All trials were video-recorded (60 Hz) in order to assess average speed, stroke rate, stroke length, five stroke phases and index of coordination. When average swimming speed was compared to FREE, it was lower in PCH and HPD+PCH, and higher in HPD. Stroke rate decreased in all overloaded trials compared to FREE. The use of hand paddles and parachute increased and decreased stroke length, respectively. In addition, propulsive phase duration was increased when hand paddles were used, and time gaps shifted towards zero (no time gap), especially when hand paddles were combined with parachute. It is conceivable that the combined use of hand paddles and parachute, once allowing overloading both propulsive and resistive forces, provides a specific stimulus to improve muscle strength and propulsive continuity.

  18. Influence of fatigue on hand muscle coordination and EMG-EMG coherence during three-digit grasping

    National Research Council Canada - National Science Library

    Danna-Dos Santos, Alessander; Poston, Brach; Jesunathadas, Mark; Bobich, Lisa R; Hamm, Thomas M; Santello, Marco

    2010-01-01

    .... While the modulation of neural drive to hand muscles as a function of force has been extensively studied, much less is known about the effects of fatigue on the coordination of simultaneously active hand muscles...

  19. Coordinated upper limb training assisted with an electromyography (EMG)-driven hand robot after stroke.

    Science.gov (United States)

    Hu, X L; Tong, K Y; Wei, X J; Rong, W; Susanto, E A; Ho, S K

    2013-01-01

    An electromyography (EMG)-driven hand robot had been developed for post-stroke rehabilitation training. The effectiveness of the hand robot assisted whole upper limb training on muscular coordination was investigated on persons with chronic stroke (n=10) in this work. All subjects attended a 20-session training (3-5 times/week) by using the hand robot to practice object grasp/release and arm transportation tasks. Improvements were found in the muscle co-ordination between the antagonist muscle pair (flexor digitorum and extensor digitorum) as measured by muscle co-contractions in EMG signals; and also in the reduction of excessive muscle activities in the biceps brachii. Reduced spasticity in the fingers was also observed as measured by the Modified Ashworth Score.

  20. Difference in activity in the supplementary motor area depending on limb combination of hand-foot coordinated movements

    Directory of Open Access Journals (Sweden)

    Kento Nakagawa

    2016-10-01

    Full Text Available Periodic interlimb coordination shows lower performance when the ipsilateral hand and foot (e.g. right hand and right foot are simultaneously moved than when the contralateral hand and foot (e.g. right hand and left foot are simultaneously moved. The present study aimed to investigate how brain activity that is related to the dependence of hand-foot coordination on limb combination, using functional magnetic imaging (fMRI. Twenty-one right-handed subjects performed periodic coordinated movements of the ipsilateral or contralateral hand and foot in the same or opposite direction in the sagittal plane. Kinematic data showed that performance was lower for the ipsilateral hand-foot coordination than for the contralateral one. A comparison of brain activity between the same and opposite directions showed that there was a greater activation of supplemental motor area (SMA for ipsilateral hand-foot coordination as compared to that seen during contralateral hand-foot coordination. We speculate that this might reflect a difference in the degree of inhibition of the neural circuit that disrupts opposite directional movements between ipsilateral and contralateral hand-foot coordinated movements.

  1. Grammatical number processing and anticipatory eye movements are not tightly coordinated in English spoken language comprehension

    Directory of Open Access Journals (Sweden)

    Brian eRiordan

    2015-05-01

    Full Text Available Recent studies of eye movements in world-situated language comprehension have demonstrated that rapid processing of morphosyntactic information – e.g., grammatical gender and number marking – can produce anticipatory eye movements to referents in the visual scene. We investigated how type of morphosyntactic information and the goals of language users in comprehension affected eye movements, focusing on the processing of grammatical number morphology in English-speaking adults. Participants’ eye movements were recorded as they listened to simple English declarative (There are the lions. and interrogative (Where are the lions? sentences. In Experiment 1, no differences were observed in speed to fixate target referents when grammatical number information was informative relative to when it was not. The same result was obtained in a speeded task (Experiment 2 and in a task using mixed sentence types (Experiment 3. We conclude that grammatical number processing in English and eye movements to potential referents are not tightly coordinated. These results suggest limits on the role of predictive eye movements in concurrent linguistic and scene processing. We discuss how these results can inform and constrain predictive approaches to language processing.

  2. Hand-Eye LRF-Based Iterative Plane Detection Method for Autonomous Robotic Welding

    Directory of Open Access Journals (Sweden)

    Sungmin Lee

    2015-12-01

    Full Text Available This paper proposes a hand-eye LRF-based (laser range finder welding plane-detection method for autonomous robotic welding in the field of shipbuilding. The hand-eye LRF system consists of a 6 DOF manipulator and an LRF attached to the wrist of the manipulator. The welding plane is detected by the LRF with only the wrist's rotation to minimize a mechanical error caused by the manipulator's motion. A position on the plane is determined as an average position of the detected points on the plane, and a normal vector to the plane is determined by applying PCA (principal component analysis to the detected points. In this case, the accuracy of the detected plane is analysed by simulations with respect to the wrist's angle interval and the plane angle. As a result of the analysis, an iterative plane-detection method with the manipulator's alignment motion is proposed to improve the performance of plane detection. For verifying the feasibility and effectiveness of the proposed plane-detection method, experiments are carried out with a prototype of the hand-eye LRF-based system, which consists of a 1 DOF wrist's joint, an LRF system and a rotatable plane. In addition, the experimental results of the PCA-based plane detection method are compared with those of the two representative plane-detection methods, based on RANSAC (RANdom SAmple Consensus and the 3D Hough transform in both accuracy and computation time's points of view.

  3. The effects of skill on the eye-hand span during musical sight-reading.

    Science.gov (United States)

    Furneaux, S; Land, M F

    1999-01-01

    The eye-hand span (EHS) is the separation between eye position and hand position when sight-reading music. It can be measured in two ways: in notes (the number of notes between hand and eye; the 'note index'), or in time (the length of time between fixation and performance; the 'time index'). The EHSs of amateur and professional pianists were compared while they sight-read music. The professionals showed significantly larger note indexes than the amateurs (approximately four notes, compared to two notes), and all subjects showed similar variability in the note index. Surprisingly, the different groups of pianists showed almost identical mean time indexes (ca. 1 s), with no significant differences between any of the skill levels. However, professionals did show significantly less variation than the amateurs. The time index was significantly affected by the performance tempo: when fast tempos were imposed on performance, all subjects showed a reduction in the time index (to ca. 0.7 s), and slow tempos increased the time index (to ca. 1.3 s). This means that the length of time that information is stored in the buffer is related to performance tempo rather than ability, but that professionals can fit more information into their buffers. PMID:10643087

  4. Interacting with mobile devices by fusion eye and hand gestures recognition systems based on decision tree approach

    Science.gov (United States)

    Elleuch, Hanene; Wali, Ali; Samet, Anis; Alimi, Adel M.

    2017-03-01

    Two systems of eyes and hand gestures recognition are used to control mobile devices. Based on a real-time video streaming captured from the device's camera, the first system recognizes the motion of user's eyes and the second one detects the static hand gestures. To avoid any confusion between natural and intentional movements we developed a system to fuse the decision coming from eyes and hands gesture recognition systems. The phase of fusion was based on decision tree approach. We conducted a study on 5 volunteers and the results that our system is robust and competitive.

  5. Influence of Fatigue on Hand Muscle Coordination and EMG-EMG Coherence During Three-Digit Grasping

    OpenAIRE

    Danna-Dos Santos, Alessander; Poston, Brach; Jesunathadas, Mark; Bobich, Lisa R.; Hamm, Thomas M.; Santello, Marco

    2010-01-01

    Fingertip force control requires fine coordination of multiple hand muscles within and across the digits. While the modulation of neural drive to hand muscles as a function of force has been extensively studied, much less is known about the effects of fatigue on the coordination of simultaneously active hand muscles. We asked eight subjects to perform a fatiguing contraction by gripping a manipulandum with thumb, index, and middle fingers while matching an isometric target force (40% maximal ...

  6. Age- and Stereovision-Dependent Eye–Hand Coordination Deficits in Children With Amblyopia and Abnormal Binocularity

    Science.gov (United States)

    Grant, Simon; Suttle, Catherine; Melmoth, Dean R.; Conway, Miriam L.; Sloper, John J.

    2014-01-01

    Purpose. To examine factors contributing to eye–hand coordination deficits in children with amblyopia and impaired stereovision. Methods. Participants were 55 anisometropic or strabismic children aged 5.0 to 9.25 years with different degrees of amblyopia and abnormal binocularity, along with 28 age-matched visually-normal controls. Pilot data were obtained from four additional patients studied longitudinally at different treatment stages. Movements of the preferred hand were recorded using a 3D motion-capture system while subjects reached-to-precision grasp objects (two sizes, three locations) under binocular, dominant eye, and amblyopic/nonsighting eye conditions. Kinematic and “error” performance measures were quantified and compared by viewing condition and subject group using ANOVA, stepwise regression, and correlation analyses. Results. Movements of the younger amblyopes (age 5–6 years; n = 30) were much slower, particularly in the final approach to the objects, and contained more spatial errors in reaching (∼×1.25–1.75) and grasping (∼×1.75–2.25) under all three views (P Amblyopia severity was the main contributor to their slower movements with absent stereovision a secondary factor and the unique determinant of their increased error-rates. Older amblyopes (age 7–9 years; n = 25) spent longer contacting the objects before lifting them (P = 0.015) compared with their matched controls (n = 15), with absence of stereovision still solely related to increases in reach and grasp errors, although these occurred less frequently than in younger patients. Pilot prospective data supported these findings by showing positive treatment-related associations between improved stereovision and reach-to-grasp performance. Conclusions. Strategies that children with amblyopia and abnormal binocularity use for reach-to-precision grasping change with age, from emphasis on visual feedback during the “in-flight” approach at ages 5 to 6 years to more reliance

  7. Do bimanual coordination, tool use, and body posture contribute equally to hand preferences in bonobos?

    Science.gov (United States)

    Bardo, Ameline; Pouydebat, Emmanuelle; Meunier, Hélène

    2015-05-01

    Approximately 90% of the human population is right-handed. The emergence of this hand preference in humans is thought to be linked to the ability to execute complex tasks and habitual bipedalism. In order to test these hypotheses, the present study explored, for the first time, hand preference in relation to both body posture (seated and bipedal) and task complexity (bimanual coordination and two tool use tasks of different complexity) in bonobos (Pan paniscus). Few studies have explored the effects of both posture and task complexity on handedness, and investigations with bonobos are scarce, particularly studies on tool use. Our study aims to overcome such a gap by addressing two main questions: 1) Does a bipedal posture increase the strength of hand preference and/or create a directional bias to the use of the right hand? 2) Independent of body posture, does task complexity increase the strength of the hand preference and/or create a directional bias to the use of the right hand? Our results show that independent of body posture, the more complex the task, the more lateralization occurred. Moreover, subjects tended to be right-handed for tasks involving tool use. However, posture had no significant effect on hand preference in the tasks tested here. Therefore, for a given task, bonobos were not more lateralized in a bipedal posture than in a seated one. Task complexity might thus have contributed more than bipedal posture to the emergence of human lateralization and the preponderance of right-handedness, although a larger sample size and more data are needed to be conclusive. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. [Safety handles for ski sticks to prevent eye, hand and stomach injuries (author's transl)].

    Science.gov (United States)

    Payer, H

    1980-12-01

    Eye injuries caused by ski stick handles are rare but serious. The material and shape of the handle can be designed to prevent serious injury without adversely affecting function. Even at winter temperatures polyurethane remains moderately malleable and shock-absorbent; it is light, and is a poor heat conductor, so that the hands do not get cold quickly. The end of the handle is 8 cm in diameter; attached to this is an adjustable loop which fits around the hand. The loop opens on impact. It is thus impossible for the orbit to sustain injury and there is less danger to other injury-prone regions of the body such as the neck and stomach. The anatomically designed handles, with wide thumb supports, help prevent hand injuries, and in particular thumb injuries, to a large extent. Such injuries have occurred frequently in the past.

  9. Radiation exposure to eye lens and operator hands during endovascular procedures in hybrid operating rooms.

    Science.gov (United States)

    Attigah, Nicolas; Oikonomou, Kyriakos; Hinz, Ulf; Knoch, Thomas; Demirel, Serdar; Verhoeven, Eric; Böckler, Dittmar

    2016-01-01

    The purpose of this study was to evaluate the radiation exposure of vascular surgeons' eye lens and fingers during complex endovascular procedures in modern hybrid operating rooms. Prospective, nonrandomized multicenter study design. One hundred seventy-one consecutive patients (138 male; median age, 72.5 years [interquartile range, 65-77 years]) underwent an endovascular procedure in a hybrid operating room between March 2012 and July 2013 in two vascular centers. The dose-area product (DAP), fluoroscopy time, operating time, and amount of contrast dye were registered prospectively. For radiation dose recordings, single-use dosimeters were attached at eye level and to the ring finger of the hand next to the radiation field of the operator for each endovascular procedure. Dose recordings were evaluated by an independent institution. Before the study, precursory investigations were obtained to simulate the radiation dose to eye lens and fingers with an Alderson phantome (RSD, Long Beach, Calif). Interventions were classified into six treatment categories: endovascular repair of infrarenal abdominal aneurysm (n = 65), thoracic endovascular aortic repair (n = 32), branched endovascular aortic repair for thoracoabdominal aneurysms (n = 17), fenestrated endovascular aortic repair for complex abdominal aortic aneurysm, (n = 25), iliac branched device (n = 8), and peripheral interventions (n = 24). There was a significant correlation in DAP between both lens (P exposure to the eyes can be obtained. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  10. Generalization of motor resonance during the observation of hand, mouth, and eye movements.

    Science.gov (United States)

    Finisguerra, Alessandra; Maffongelli, Laura; Bassolino, Michela; Jacono, Marco; Pozzo, Thierry; D'Ausilio, Alessandro

    2015-10-01

    Transcranial magnetic stimulation (TMS) of the motor cortex shows that hand action observation (AO) modulates corticospinal excitability (CSE). CSE modulation alternatively maps low-level kinematic characteristics or higher-level features, like object-directed action goals. However, action execution is achieved through the control of muscle synergies, consisting of coordinated patterns of muscular activity during natural movements, rather than single muscles or object-directed goals. This synergistic organization of action execution also underlies the ability to produce the same functional output (i.e., grasping an object) using different effectors. We hypothesize that motor system activation during AO may rely on similar principles. To investigate this issue, we recorded both hand CSE and TMS-evoked finger movements which provide a much more complete description of coordinated patterns of muscular activity. Subjects passively watched hand, mouth and eyelid opening or closing, which are performing non-object-directed (intransitive) actions. Hand and mouth share the same potential to grasp objects, whereas eyelid does not allow object-directed (transitive) actions. Hand CSE modulation generalized to all effectors, while TMS evoked finger movements only to mouth AO. Such dissociation suggests that the two techniques may have different sensitivities to fine motor modulations induced by AO. Differently from evoked movements, which are sensitive to the possibility to achieve object-directed action, CSE is generically modulated by "opening" vs. "closing" movements, independently of which effector was observed. We propose that motor activities during AO might exploit the same synergistic mechanisms shown for the neural control of movement and organized around a limited set of motor primitives. Copyright © 2015 the American Physiological Society.

  11. The coordinate system of the eye in cataract surgery: Performance comparison of the circle Hough transform and Daugman's algorithm

    Science.gov (United States)

    Vlachynska, Alzbeta; Oplatkova, Zuzana Kominkova; Sramka, Martin

    2017-07-01

    The aim of the work is to determine the coordinate system of an eye and insert a polar-axis system into images captured by a slip lamp. The image of the eye with the polar axis helps a surgeon accurately implant toric intraocular lens in the required position/rotation during the cataract surgery. In this paper, two common algorithms for pupil detection are compared: the circle Hough transform and Daugman's algorithm. The procedures were tested and analysed on the anonymous data set of 128 eyes captured at Gemini eye clinic in 2015.

  12. Eye Tracking of Occluded Self-Moved Targets: Role of Haptic Feedback and Hand-Target Dynamics.

    Science.gov (United States)

    Danion, Frederic; Mathew, James; Flanagan, J Randall

    2017-01-01

    Previous studies on smooth pursuit eye movements have shown that humans can continue to track the position of their hand, or a target controlled by the hand, after it is occluded, thereby demonstrating that arm motor commands contribute to the prediction of target motion driving pursuit eye movements. Here, we investigated this predictive mechanism by manipulating both the complexity of the hand-target mapping and the provision of haptic feedback. Two hand-target mappings were used, either a rigid (simple) one in which hand and target motion matched perfectly or a nonrigid (complex) one in which the target behaved as a mass attached to the hand by means of a spring. Target animation was obtained by asking participants to oscillate a lightweight robotic device that provided (or not) haptic feedback consistent with the target dynamics. Results showed that as long as 7 s after target occlusion, smooth pursuit continued to be the main contributor to total eye displacement (∼60%). However, the accuracy of eye-tracking varied substantially across experimental conditions. In general, eye-tracking was less accurate under the nonrigid mapping, as reflected by higher positional and velocity errors. Interestingly, haptic feedback helped to reduce the detrimental effects of target occlusion when participants used the nonrigid mapping, but not when they used the rigid one. Overall, we conclude that the ability to maintain smooth pursuit in the absence of visual information can extend to complex hand-target mappings, but the provision of haptic feedback is critical for the maintenance of accurate eye-tracking performance.

  13. No One Even Has Eyes: The Decline of Hand-Painted Graphics in Mumbai

    Directory of Open Access Journals (Sweden)

    Aaron Fine

    2013-05-01

    Full Text Available In this work of creative non-fiction, accompanied by coloring book plates of his own design, the author explores recent changes in Indian visual culture. An investigation of hand painted political graphics in Mumbai revealed very little painting and a great deal about the rapidly advancing digitalization of visual space in India. As idiosyncratic and individual creative efforts are replaced by mass-produced digital printing in what ways are India’s political networks enhanced; In what ways are India’s creative networks destroyed? Translators, police officers, political activists, and artists are presented through the eyes of an outsider whose own expectations about creative expression and political participation are challenged. The conclusion considers how once recycled visual culture artifacts are now junk destined for the landfill, and urges readers to color-in the whitewashed spaces of the city.

  14. An improved robust hand-eye calibration for endoscopy navigation system

    Science.gov (United States)

    He, Wei; Kang, Kumsok; Li, Yanfang; Shi, Weili; Miao, Yu; He, Fei; Yan, Fei; Yang, Huamin; Zhang, Huimao; Mori, Kensaku; Jiang, Zhengang

    2016-03-01

    Endoscopy is widely used in clinical application, and surgical navigation system is an extremely important way to enhance the safety of endoscopy. The key to improve the accuracy of the navigation system is to solve the positional relationship between camera and tracking marker precisely. The problem can be solved by the hand-eye calibration method based on dual quaternions. However, because of the tracking error and the limited motion of the endoscope, the sample motions may contain some incomplete motion samples. Those motions will cause the algorithm unstable and inaccurate. An advanced selection rule for sample motions is proposed in this paper to improve the stability and accuracy of the methods based on dual quaternion. By setting the motion filter to filter out the incomplete motion samples, finally, high precision and robust result is achieved. The experimental results show that the accuracy and stability of camera registration have been effectively improved by selecting sample motion data automatically.

  15. Hand-eye calibration for rigid laparoscopes using an invariant point.

    Science.gov (United States)

    Thompson, Stephen; Stoyanov, Danail; Schneider, Crispin; Gurusamy, Kurinchi; Ourselin, Sébastien; Davidson, Brian; Hawkes, David; Clarkson, Matthew J

    2016-06-01

    Laparoscopic liver resection has significant advantages over open surgery due to less patient trauma and faster recovery times, yet it can be difficult due to the restricted field of view and lack of haptic feedback. Image guidance provides a potential solution but one current challenge is in accurate "hand-eye" calibration, which determines the position and orientation of the laparoscope camera relative to the tracking markers. In this paper, we propose a simple and clinically feasible calibration method based on a single invariant point. The method requires no additional hardware, can be constructed by theatre staff during surgical setup, requires minimal image processing and can be visualised in real time. Real-time visualisation allows the surgical team to assess the calibration accuracy before use in surgery. In addition, in the laboratory, we have developed a laparoscope with an electromagnetic tracking sensor attached to the camera end and an optical tracking marker attached to the distal end. This enables a comparison of tracking performance. We have evaluated our method in the laboratory and compared it to two widely used methods, "Tsai's method" and "direct" calibration. The new method is of comparable accuracy to existing methods, and we show RMS projected error due to calibration of 1.95 mm for optical tracking and 0.85 mm for EM tracking, versus 4.13 and 1.00 mm respectively, using existing methods. The new method has also been shown to be workable under sterile conditions in the operating room. We have proposed a new method of hand-eye calibration, based on a single invariant point. Initial experience has shown that the method provides visual feedback, satisfactory accuracy and can be performed during surgery. We also show that an EM sensor placed near the camera would provide significantly improved image overlay accuracy.

  16. HotEye (tm) Based Coordinate Measuring Machine for Forging Industry

    Energy Technology Data Exchange (ETDEWEB)

    OG Technologies

    2003-06-09

    The objective of this project is to develop a 3 dimensional measurement system for the domestic forging industry based on HotEye{trademark}. This technology will allow high definition camera to accurately image a red hot object. The project marries conventional Coordinate Measurement Machine ''CMM'' technology to HotEye{trademark} technology to permit the accurate measurement of forged parts while they are at high temperature. Being able to take such measurements will dramatically reduce the amount of scrap produced by the domestic forging industry. This industry wastes a significant amount of energy because of the high rate of scrap it produces. OGT will: (1) Develop a 3D measurement sensor head that will work on a part at a temperature up to 1,450 C with an accuracy of 0.1mm or better and with a scanning speed of less than 10 seconds for an area of 100mm x 100mm. (2) Develop a Virtual-Fixturing software package to alleviate the need of precise hard fixturing. (3) Integrate the 3D measurement sensor head and the Virtual-Fixturing software into a standard CMM, both hardware (replacing the probes) and software (data format and user interface match) so that the system can automatically perform a complete preprogrammed measurement of a hot product. (4) Test and evaluate the system in a forging facility.

  17. Cross-modal recognition of shape from hand to eyes in human newborns.

    Science.gov (United States)

    Streri, Arlette

    2003-01-01

    The hypothesis that the ability to coordinate information between tactual and visual modalities is present at birth and dependent on perceptual inherent structures was tested in human newborns. Using an intersensory paired-preference procedure, we showed that newborns can visually recognize the shape of an object that they have previously manipulated with their right hand, out of sight. This is an experimental evidence that newborns can extract shape information in a tactual format and transform it in a visual format before they have had the opportunity to learn from the pairings of visual and tactual experience. This is contrary to a host of theories and models of perceptual learning, both traditional (empiricist philosophers) and modern (connectionist).

  18. Design of an eye-in-hand sensing and servo control framework for harvesting robotics in dense vegetation

    NARCIS (Netherlands)

    Barth, Ruud; Hemming, Jochen; Henten, van E.J.

    2016-01-01

    A modular software framework design that allows flexible implementation of eye-in-hand sensing and motion control for agricultural robotics in dense vegetation is reported. Harvesting robots in cultivars with dense vegetation require multiple viewpoints and on-line trajectory adjustments in order

  19. The Hands with Eyes and Nose in the Palm: As Effective Communication Alternatives for Profoundly Deaf People in Zimbabwe

    Science.gov (United States)

    Mutswanga, Phillipa

    2017-01-01

    Drawing from the experiences and testimonies of people with profound deafness, the study qualitatively explored the use of the hands with eyes and nose in the palm as communication alternatives in the field of deafness. The study was prompted by the 27 year old lady, Leah Katz-Hernandez who is deaf who got engaged in March 2015 as the 2016…

  20. Influence of fatigue on hand muscle coordination and EMG-EMG coherence during three-digit grasping.

    Science.gov (United States)

    Danna-Dos Santos, Alessander; Poston, Brach; Jesunathadas, Mark; Bobich, Lisa R; Hamm, Thomas M; Santello, Marco

    2010-12-01

    Fingertip force control requires fine coordination of multiple hand muscles within and across the digits. While the modulation of neural drive to hand muscles as a function of force has been extensively studied, much less is known about the effects of fatigue on the coordination of simultaneously active hand muscles. We asked eight subjects to perform a fatiguing contraction by gripping a manipulandum with thumb, index, and middle fingers while matching an isometric target force (40% maximal voluntary force) for as long as possible. The coordination of 12 hand muscles was quantified as electromyographic (EMG) muscle activation pattern (MAP) vector and EMG-EMG coherence. We hypothesized that muscle fatigue would cause uniform changes in EMG amplitude across all muscles and an increase in EMG-EMG coherence in the higher frequency bands but with an invariant heterogeneous distribution across muscles. Muscle fatigue caused a 12.5% drop in the maximum voluntary contraction force (P muscles increased during the fatiguing contraction (P muscle coordination pattern was used throughout the fatiguing contraction. Last, EMG-EMG coherence (0-35 Hz) was significantly greater at the end than at the beginning of the fatiguing contraction (P muscles. These findings suggest that similar mechanisms are involved for modulating and sustaining digit forces in nonfatiguing and fatiguing contractions, respectively.

  1. Eye movements are coordinated with pectoral fin beats during locomotion in a marine teleost fish.

    Science.gov (United States)

    Mandecki, Joanna L; Domenici, Paolo

    2015-04-15

    Animals must simultaneously engage multiple functional systems in order to navigate, feed and survive in complex environments. Nearly all vertebrates perform rapid gaze-shifting eye movements called saccades, but we know little about the behaviour of saccades during rhythmic locomotion. This study examined how saccades are coordinated with locomotor movements in a pectoral-fin-propelled teleost fish, Cymatogaster aggregata, the shiner surfperch. Individual fish were filmed swimming in a flow tank at 10 cm s(-1), and timing data were analysed using circular statistics. The results reveal that C. aggregata generates saccades non-uniformly throughout the pectoral fin cycle. Saccades primarily occur during fin abduction, when a large amount of thrust is produced, and rarely occur during the thrust-free refractory phase. Because vision is known to be impaired during saccades, we hypothesize that C. aggregata synchronizes saccades with periods of high acceleration in order to stabilize retinal images during low-acceleration phases, which are nearly saccade-free. © 2015. Published by The Company of Biologists Ltd.

  2. The Effects of a Pitched Field Orientation on Hand/Eye Coordination

    Science.gov (United States)

    1988-09-01

    muscles that support the weight of the body. This increased body weight causes additional tensions produced in the antigravity muscles and increased...proprioceptive receptors fall within Sherrington’s framework. These are the muscle proprioceptors, the joint and cutaneous proprioceptors, and the...1:pp. 176-177] Neuromuscular spindles and Golgi tendon organs are muscle proprioceptive receptors that reside within the gross structure of most

  3. Hand washing induces a clean slate effect in moral judgments: a pupillometry and eye-tracking study.

    Science.gov (United States)

    Kaspar, Kai; Krapp, Vanessa; König, Peter

    2015-05-21

    Physical cleansing is commonly understood to protect us against physical contamination. However, recent studies showed additional effects on moral judgments. Under the heading of the "Macbeth effect" direct links between bodily cleansing and one's own moral purity have been demonstrated. Here we investigate (1) how moral judgments develop over time and how they are altered by hand washing, (2) whether changes in moral judgments can be explained by altered information sampling from the environment, and (3) whether hand washing affects emotional arousal. Using a pre-post control group design, we found that morality ratings of morally good and bad scenes acquired more extreme values in the control group over time, an effect that was fully counteracted by intermediate hand washing. This result supports the notion of a clean slate effect by hand washing. Thereby, eye-tracking data did not uncover differences in eye movement behavior that may explain differences in moral judgments. Thus, the clean slate effect is not due to altered information sampling from the environment. Finally, compared to the control group, pupil diameter decreased after hand washing, thus demonstrating a direct physiological effect. The results shed light on the physiological mechanisms behind this type of embodiment phenomenon.

  4. Hand-Camera Coordination Varies over Time in Users of the Argus® II Retinal Prosthesis System

    Directory of Open Access Journals (Sweden)

    Michael P Barry

    2016-05-01

    , bootstrap MANOVA, up to 21°–29° within subjects over the observed period. Across subjects, optimal CAPs showed an average rate of change of 0.39°/day (SD 0.36°/day.Conclusions:Optimal CAPs varied dramatically over time for all subjects. Subjects displayed no adaptation to misaligned CAPs without feedback. Regular recalibration of CAPs may be required to maintain hand-camera coordination.

  5. Design and characterization of the OpenWrist: A robotic wrist exoskeleton for coordinated hand-wrist rehabilitation.

    Science.gov (United States)

    Pezent, Evan; Rose, Chad G; Deshpande, Ashish D; O'Malley, Marcia K

    2017-07-01

    Robotic devices have been clinically verified for use in long duration and high intensity rehabilitation needed for motor recovery after neurological injury. Targeted and coordinated hand and wrist therapy, often overlooked in rehabilitation robotics, is required to regain the ability to perform activities of daily living. To this end, a new coupled hand-wrist exoskeleton has been designed. This paper details the design of the wrist module and several human-related considerations made to maximize its potential as a coordinated hand-wrist device. The serial wrist mechanism has been engineered to facilitate donning and doffing for impaired subjects and to insure compatibility with the hand module in virtual and assisted grasping tasks. Several other practical requirements have also been addressed, including device ergonomics, clinician-friendliness, and ambidextrous reconfigurability. The wrist module's capabilities as a rehabilitation device are quantified experimentally in terms of functional workspace and dynamic properties. Specifically, the device possesses favorable performance in terms of range of motion, torque output, friction, and closed-loop position bandwidth when compared with existing devices. The presented wrist module's performance and operational considerations support its use in a wide range of future clinical investigations.

  6. Control model for dampening hand vibrations using information of internal and external coordinates.

    Science.gov (United States)

    Togo, Shunta; Kagawa, Takahiro; Uno, Yoji

    2015-01-01

    In the present study, we investigate a control mechanism that dampens hand vibrations. Here, we propose a control method with two components to suppress hand vibrations. The first is a passive suppression method that lowers the joint stiffness to passively dampen the hand vibrations. The second is an active suppression method that adjusts an equilibrium point based on skyhook control to actively dampen the hand vibrations. In a simulation experiment, we applied these two methods to dampen hand vibrations during the shoulder's horizontal oscillation. We also conducted a measurement experiment wherein a subject's shoulder was sinusoidally oscillated by a platform that generated horizontal oscillations. The results of the measurement experiments showed that the jerk of each part of the arm in a task using a cup filled with water was smaller than the shoulder jerk and that in a task with a cup filled with stones was larger than the shoulder jerk. Moreover, the amplitude of the hand trajectory in both horizontal and vertical directions was smaller in a task using a cup filled with water than in a task using a cup filled with stones. The results of the measurement experiments were accurately reproduced by the active suppression method based on skyhook control. These results suggest that humans dampen hand vibrations by controlling the equilibrium point through the information of the external workspace and the internal body state rather than by lowering joint stiffness only by using internal information.

  7. Control model for dampening hand vibrations using information of internal and external coordinates.

    Directory of Open Access Journals (Sweden)

    Shunta Togo

    Full Text Available In the present study, we investigate a control mechanism that dampens hand vibrations. Here, we propose a control method with two components to suppress hand vibrations. The first is a passive suppression method that lowers the joint stiffness to passively dampen the hand vibrations. The second is an active suppression method that adjusts an equilibrium point based on skyhook control to actively dampen the hand vibrations. In a simulation experiment, we applied these two methods to dampen hand vibrations during the shoulder's horizontal oscillation. We also conducted a measurement experiment wherein a subject's shoulder was sinusoidally oscillated by a platform that generated horizontal oscillations. The results of the measurement experiments showed that the jerk of each part of the arm in a task using a cup filled with water was smaller than the shoulder jerk and that in a task with a cup filled with stones was larger than the shoulder jerk. Moreover, the amplitude of the hand trajectory in both horizontal and vertical directions was smaller in a task using a cup filled with water than in a task using a cup filled with stones. The results of the measurement experiments were accurately reproduced by the active suppression method based on skyhook control. These results suggest that humans dampen hand vibrations by controlling the equilibrium point through the information of the external workspace and the internal body state rather than by lowering joint stiffness only by using internal information.

  8. Eye-Hand Synergy and Intermittent Behaviors during Target-Directed Tracking with Visual and Non-visual Information

    Science.gov (United States)

    Huang, Chien-Ting; Hwang, Ing-Shiou

    2012-01-01

    Visual feedback and non-visual information play different roles in tracking of an external target. This study explored the respective roles of the visual and non-visual information in eleven healthy volunteers who coupled the manual cursor to a rhythmically moving target of 0.5 Hz under three sensorimotor conditions: eye-alone tracking (EA), eye-hand tracking with visual feedback of manual outputs (EH tracking), and the same tracking without such feedback (EHM tracking). Tracking error, kinematic variables, and movement intermittency (saccade and speed pulse) were contrasted among tracking conditions. The results showed that EHM tracking exhibited larger pursuit gain, less tracking error, and less movement intermittency for the ocular plant than EA tracking. With the vision of manual cursor, EH tracking achieved superior tracking congruency of the ocular and manual effectors with smaller movement intermittency than EHM tracking, except that the rate precision of manual action was similar for both types of tracking. The present study demonstrated that visibility of manual consequences altered mutual relationships between movement intermittency and tracking error. The speed pulse metrics of manual output were linked to ocular tracking error, and saccade events were time-locked to the positional error of manual tracking during EH tracking. In conclusion, peripheral non-visual information is critical to smooth pursuit characteristics and rate control of rhythmic manual tracking. Visual information adds to eye-hand synchrony, underlying improved amplitude control and elaborate error interpretation during oculo-manual tracking. PMID:23236498

  9. Pensar con el ojo, pensar con la mano = Thinking with your eye, thinking with your hand

    Directory of Open Access Journals (Sweden)

    Juan Manuel Sánchez de la Chica

    2013-10-01

    AbstractDefining architecture as visual-functional art, Asis Cabrero goes back to the origins of the human species to explain the elements of conscience involved in the work of humankind. Human survival is voluntary, variable, personal and inventive in sharp contrast with the instinct of nature's other species. Humans are intelligent beings whose thinking is determined by their sense of sight, by the ability of their hands to make tools, on top of their predatory nature. This human animal of exchangeable organs is able to specialize himself in the use of tools he makes to be on equal terms with specialized animals. So does man make tools to come face to face with a variable and changing nature, be it a knife, an ax or a shelter.Since Architecture is a product of what your eye sees, it is the functional use of your hand that comes into play in Architectural drawings. According to Cabrero, matter becomes material through tools, to be rigged, to be built. Tools which have evolved over the course of history as matter always remain unchanged in nature. Asís Cabrero has researched five primitive architectures related to five original matters. He has studied the dome structure, the lintel, the framework, the laminated structure and the removable structure in connection with the rational use of clay, stone, wood, branches and skin.The variety of available materials in the professional career of Asís Cabrero, from post-war isolation to the liberalization of the sixties, allow us to set five ages in the work of Francisco de Asís Cabrero according to the material and the tools he uses.Key wordsFrancisco Cabrero, architecture, instruments, material, structure, tools

  10. Altered eye-to-foot coordination in standing parkinsonian patients during large gaze and whole-body reorientations.

    Science.gov (United States)

    Anastasopoulos, Dimitri; Ziavra, Nafsica; Savvidou, Eugenia; Bain, Peter; Bronstein, Adolfo M

    2011-10-01

    We investigated whether turning problems in Parkinson's disease may be the result of abnormal horizontal multisegmental angular coordination. Ten mildly affected patients and controls stood upright and voluntarily reoriented eyes and body to illuminated targets of eccentricities up to ±180 degrees. The effects of target location, visibility, and predictability on movement parameters were evaluated. Patients' latencies were normal. Control subjects foveated large eccentricity targets with a single gaze shift in approximately 30% of predictable trials. Patients rarely did so (10% of predictable trials) because of reduced head-in-space and trunk velocity. This resulted in massive foveation delays in patients-an average of half a second for displacements of 180 degrees. The covariation of eye, head, and trunk rotations was quantified statistically by means of principal components analysis. In both groups, the combined movement was initially stereotyped and two principal components accounted for nearly all data variance-the original three mechanical degrees of freedom (i.e., eye-head-trunk) are reduced to two kinematic degrees of freedom. However, in patients, the eye contributed more, and the head and trunk less, to the gaze shift than in control subjects. Although the eye-to-foot turning synergy is preserved in early-stage parkinsonism, quantitative differences are prominent, particularly a larger ocular (and smaller head-trunk) contribution in patients. Turning problems in Parkinson's disease do not result from inability to assemble multisegmental movements, as patients' ability to control numerous degrees of freedom is preserved. However, trunk bradykinesia reduces the frequency of single-step gaze shifts, thus prolonging target acquisition time. Preserved eye motion compensates for trunk slowness. Copyright © 2011 Movement Disorder Society.

  11. Hand and Eye Dominance in Sport: Are Cricket Batters Taught to Bat Back-to-Front?

    Science.gov (United States)

    Mann, David L; Runswick, Oliver R; Allen, Peter M

    2016-09-01

    When first learning to bimanually use a tool to hit a target (e.g., when chopping wood or hitting a golf ball), most people assume a stance that is dictated by their dominant hand. By convention, this means that a 'right-handed' or 'left-handed' stance that places the dominant hand closer to the striking end of the tool is adopted in many sports. The aim of this study was to investigate whether the conventional stance used for bimanual hitting provides the best chance of developing expertise in that task. Our study included 43 professional (international/first-class) and 93 inexperienced (back-to-front' and have a significant disadvantage in the game. Moreover, the results may generalize more widely, bringing into question the way in which other bimanual sporting actions are taught and performed.

  12. Real Time Eye Tracking and Hand Tracking Using Regular Video Cameras for Human Computer Interaction

    Science.gov (United States)

    2011-01-01

    Expo (ICME 2010), July 2010, Singapore. (15% acceptance rate)  Kaoning Hu, Shaun Canavan , and Lijun Yin, “Hand pointing estimation for human computer...Computing, Dec. 2009. Las Vegas, NV  Shaun Canavan and Lijun Yin, Dynamic face appearance modeling and sight direction estimation based on local...Kaoning Hu, Shaun Canavan , and Lijun Yin, “Hand pointing estimation for human computer interaction based on two orthogonal views”, IEEE/IAPR

  13. Digital fringe projection for hand surface coordinate variation analysis caused by osteoarthritis

    Science.gov (United States)

    Nor Haimi, Wan Mokhdzani Wan; Hau Tan, Cheek; Retnasamy, Vithyacharan; Vairavan, Rajendaran; Sauli, Zaliman; Roshidah Yusof, Nor; Hambali, Nor Azura Malini Ahmad; Aziz, Muhammad Hafiz Ab; Bakhit, Ahmad Syahir Ahmad

    2017-11-01

    Hand osteoarthritis is one of the most common forms of arthritis which impact millions of people worldwide. The disabling problem occurs when the protective cartilage on the boundaries of bones wear off over time. Currently, in order to identify hand osteoarthritis, special instruments namely X-ray scanning and MRI are used for the detection but it also has its limitations such as radiation exposure and can be quite costly. In this work, an optical metrology system based on digital fringe projection which comprises of an LCD projector, CCD camera and a personal computer has been developed to anticipate abnormal growth or deformation on the joints of the hand which are common symptoms of osteoarthritis. The main concept of this optical metrology system is to apply structured light as imaging source for surface change detection. The imaging source utilizes fringe patterns generated by C++ programming and is shifted by 3 phase shifts based on the 3 steps 2 shifts method. Phase wrapping technique and analysis were applied in order to detect the deformation of live subjects. The result has demonstrated a successful method of hand deformation detection based on the pixel tracking differences of a normal and deformed state.

  14. Coordination of eye and head movements during smooth pursuit in patients with vestibular failure.

    Science.gov (United States)

    Waterston, J A; Barnes, G R; Grealy, M A; Luxon, L M

    1992-12-01

    During pursuit of smoothly moving targets with combined eye and head movements in normal subjects, accurate gaze control depends on successful interaction of the vestibular and head movement signals with the ocular pursuit mechanisms. To investigate compensation for loss of the vestibulo-ocular reflex during head-free pursuit in labyrinthine-deficient patients, pursuit performance was assessed and compared under head-fixed and head-free conditions in five patients with isolated bilateral loss of vestibular function. Target motion consisted of predictable and unpredictable pseudo-random waveforms containing the sum of three or four sinusoids. Comparison of slow-phase gaze velocity gains under head-free and head-fixed conditions revealed no significant differences during pursuit of any of the three pseudo-random waveforms. The finding of significant compensatory eye movement during active head movements in darkness in labyrinthine-deficient patients, which were comparable in character and gain to the vestibular eye movement elicited in normal subjects, probably explains the similarity of the head-fixed and head-free responses. In two additional patients with cerebellar degeneration and vestibular failure, no compensatory eye movement response was observed, implying that the cerebellum is necessary for the generation of such responses in labyrinthine-deficient patients.

  15. Target Selection by the Frontal Cortex during Coordinated Saccadic and Smooth Pursuit Eye Movements

    Science.gov (United States)

    Srihasam, Krishna; Bullock, Daniel; Grossberg, Stephen

    2009-01-01

    Oculomotor tracking of moving objects is an important component of visually based cognition and planning. Such tracking is achieved by a combination of saccades and smooth-pursuit eye movements. In particular, the saccadic and smooth-pursuit systems interact to often choose the same target, and to maximize its visibility through time. How do…

  16. Effectiveness of pelvic lead blanket to reduce the doses to eye lens and hands of interventional cardiologists and assistant nurses.

    Science.gov (United States)

    Grabowicz, W; Domienik-Andrzejewska, J; Masiarek, K; Górnik, T; Grycewicz, T; Brodecki, M; Lubiński, A

    2017-09-01

    The aim of the present study is to analyse quantitatively the potential reduction of doses to the eye lens and the hands of an operator and a nurse by the use of a pelvic lead blanket during coronary angiography (CA) and percutaneous transluminal coronary angioplasty (PTCA) procedures. Thermoluminescent dosimeters were used to assess dose levels to the left eye lens and fingers on both hands of both physician and nurses during single procedures performed with or without the lead blanket. The measurements were carried out at one medical centre and include dosimetric data from 100 procedures. Additional measurements including physician's and patient's doses were made on phantoms in the laboratory. In order to determine the reduction potential of the lead blanket, the doses normalized to DAP (Dose-Area Product) corresponding to the same position of dosimeter were compared against each other for both procedure categories (with and without protection). There was no statistically significant decrease observed in physicians' and nurses' eye lens doses, nor in doses normalized to DAP due to the use of the lead pelvic shield in clinic. However, some trend in reducing the eye lens doses by this shield can be observed. Regarding finger doses, the differences are statistically significant but only for physicians. The mean DAP-normalised doses to the eye lens and left and right finger of physicians, in the presence of a ceiling-suspended transparent lead shield, were 2.24e-5 ± 1.41e-5 mSv/μGym 2 , 2.31e-4 ± 1.21e-4 mSv/μGym 2 , and 2.60e-5 ± 1.57e-5 mSv/μGym 2 for standard procedures performed without the lead blanket, and 1.77e-5 ± 1.17e-5 mSv/μGym 2 , 1.70e-4 ± 1.01e-4 mSv/μGym 2 , and 1.86e-5 ± 1.13e-5 mSv/μGym 2 for procedures performed with it. A comparison of the results from the laboratory and the clinic shows that they are consistent regarding the eye lens, while for fingers it suggests that the dose reduction properties of the lead shield are related to the

  17. Saccades and eye-head coordination in ataxia with oculomotor apraxia type 2.

    Science.gov (United States)

    Panouillères, Muriel; Frismand, Solène; Sillan, Olivier; Urquizar, Christian; Vighetto, Alain; Pélisson, Denis; Tilikete, Caroline

    2013-08-01

    Ataxia with oculomotor apraxia type 2 (AOA2) is one of the most frequent autosomal recessive cerebellar ataxias. Oculomotor apraxia refers to horizontal gaze failure due to deficits in voluntary/reactive eye movements. These deficits can manifest as increased latency and/or hypometria of saccades with a staircase pattern and are frequently associated with compensatory head thrust movements. Oculomotor disturbances associated with AOA2 have been poorly studied mainly because the diagnosis of oculomotor apraxia was based on the presence of compensatory head thrusts. The aim of this study was to characterise the nature of horizontal gaze failure in patients with AOA2 and to demonstrate oculomotor apraxia even in the absence of head thrusts. Five patients with AOA2, without head thrusts, were tested in saccadic tasks with the head restrained or free to move and their performance was compared to a group of six healthy participants. The most salient deficit of the patients was saccadic hypometria with a typical staircase pattern. Saccade latency in the patients was longer than controls only for memory-guided saccades. In the head-free condition, head movements were delayed relative to the eye and their amplitude and velocity were strongly reduced compared to controls. Our study emphasises that in AOA2, hypometric saccades with a staircase pattern are a more reliable sign of oculomotor apraxia than head thrust movements. In addition, the variety of eye and head movements' deficits suggests that, although the main neural degeneration in AOA2 affects the cerebellum, this disease affects other structures.

  18. Dual logic and cerebral coordinates for reciprocal interaction in eye contact.

    Science.gov (United States)

    Lee, Ray F

    2015-01-01

    In order to scientifically study the human brain's response to face-to-face social interaction, the scientific method itself needs to be reconsidered so that both quantitative observation and symbolic reasoning can be adapted to the situation where the observer is also observed. In light of the recent development of dyadic fMRI which can directly observe dyadic brain interacting in one MRI scanner, this paper aims to establish a new form of logic, dual logic, which provides a theoretical platform for deductive reasoning in a complementary dual system with emergence mechanism. Applying the dual logic in the dfMRI experimental design and data analysis, the exogenous and endogenous dual systems in the BOLD responses can be identified; the non-reciprocal responses in the dual system can be suppressed; a cerebral coordinate for reciprocal interaction can be generated. Elucidated by dual logic deductions, the cerebral coordinate for reciprocal interaction suggests: the exogenous and endogenous systems consist of the empathy network and the mentalization network respectively; the default-mode network emerges from the resting state to activation in the endogenous system during reciprocal interaction; the cingulate plays an essential role in the emergence from the exogenous system to the endogenous system. Overall, the dual logic deductions are supported by the dfMRI experimental results and are consistent with current literature. Both the theoretical framework and experimental method set the stage to formally apply the scientific method in studying complex social interaction.

  19. An eye for accuracy: Coordinate measuring in an R and D environment

    Energy Technology Data Exchange (ETDEWEB)

    Kobliska, G.R.

    1988-06-01

    The Fermi National Accelerator Laboratory (Fermilab) is a high energy physics research facility. Its purpose is to explore the basic composition of matter. Fermilab does not produce a product nor does it produce electrical power. Funded by the Department of Energy, the main tool for its study is the Tevatron, the world's first superconducting particle accelerator. Fermilab fabricates and assembles the majority of magnets and other components for the accelerator rings of the atom smasher. The magnet is the key to accelerating subatomic particle (i.e., protons, anti-protons, etc.) which the particle accelerator uses to collide into other beams or fixed targets. The production of a magnet assembly requires stacking steel laminations precisely the proper size and shape necessary to create the required magnetic field. In this paper, it will be discussed how coordinate measuring is accomplished at Fermilab, and how such things as tight budgets, and lack of product line can lead to some interesting and useful techniques. 6 figs.

  20. Robot-assisted retinal vein cannulation with force-based puncture detection: Micron vs. the steady-hand eye robot.

    Science.gov (United States)

    Gonenc, Berk; Tran, Nhat; Gehlbach, Peter; Taylor, Russell H; Iordachita, Iulian

    2016-08-01

    Retinal vein cannulation is a demanding procedure where therapeutic agents are injected into occluded retina veins. The feasibility of this treatment is limited due to challenges in identifying the moment of venous puncture, achieving cannulation and maintaining it throughout the drug delivery period. In this study, we integrate a force-sensing microneedle with two distinct robotic systems: the handheld micromanipulator Micron, and the cooperatively controlled Steady-Hand Eye Robot (SHER). The sensed tool-to-tissue interaction forces are used to detect venous puncture and extend the robots' standard control schemes with a new position holding mode (PHM) that assists the operator hold the needle position fixed and maintain cannulation for a longer time with less trauma on the vasculature. We evaluate the resulting systems comparatively in a dry phantom, stretched vinyl membranes. Results have shown that modulating the admittance control gain of SHER alone is not a very effective solution for preventing the undesired tool motion after puncture. However, after using puncture detection and PHM the deviation from the puncture point is significantly reduced, by 65% with Micron, and by 95% with SHER representing a potential advantage over freehand for both.

  1. Hand-Ground Nanoscale ZnII-Based Coordination Polymers Derived from NSAIDs: Cell Migration Inhibition of Human Breast Cancer Cells.

    Science.gov (United States)

    Paul, Mithun; Sarkar, Koushik; Deb, Jolly; Dastidar, Parthasarathi

    2017-04-27

    Increased levels of intracellular prostaglandin E 2 (PGE 2 ) have been linked with the unregulated cancer cell migration that often leads to metastasis. Non-steroidal anti-inflammatory drugs (NSAIDs) are known inhibitors of cyclooxygenase (COX) enzymes, which are responsible for the increased PGE 2 concentration in inflamed as well as cancer cells. Here, we demonstrate that NSAID-derived Zn II -based coordination polymers are able to inhibit cell migration of human breast cancer cells. Various NSAIDs were anchored to a series of 1D Zn II coordination polymers through carboxylate-Zn coordination, and these structures were fully characterized by single-crystal X-ray diffraction. Hand grinding in a pestle and mortar resulted in the first reported example of nanoscale coordination polymers that were suitable for biological studies. Two such hand-ground nanoscale coordination polymers NCP1 a and NCP2 a, which contained naproxen (a well-studied NSAID), were successfully internalized by the human breast cancer cells MDA-MB-231, as was evident from cellular imaging by using a fluorescence microscope. They were able to kill the cancer cells (MTT assay) more efficiently than the corresponding mother drug naproxen, and most importantly, they significantly inhibited cancer cell migration thereby displaying anticancer activity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Manual tracking enhances smooth pursuit eye movements.

    Science.gov (United States)

    Niehorster, Diederick C; Siu, Wilfred W F; Li, Li

    2015-01-01

    Previous studies have reported that concurrent manual tracking enhances smooth pursuit eye movements only when tracking a self-driven or a predictable moving target. Here, we used a control-theoretic approach to examine whether concurrent manual tracking enhances smooth pursuit of an unpredictable moving target. In the eye-hand tracking condition, participants used their eyes to track a Gaussian target that moved randomly along a horizontal axis. In the meantime, they used their dominant hand to move a mouse to control the horizontal movement of a Gaussian cursor to vertically align it with the target. In the eye-alone tracking condition, the target and cursor positions recorded in the eye-hand tracking condition were replayed, and participants only performed eye tracking of the target. Catch-up saccades were identified and removed from the recorded eye movements, allowing for a frequency-response analysis of the smooth pursuit response to unpredictable target motion. We found that the overall smooth pursuit gain was higher and the number of catch-up saccades made was less when eye tracking was accompanied by manual tracking than when not. We conclude that concurrent manual tracking enhances smooth pursuit. This enhancement is a fundamental property of eye-hand coordination that occurs regardless of the predictability of the target motion.

  3. Investigation of the Intra- and Inter-Limb Muscle Coordination of Hands-and-Knees Crawling in Human Adults by Means of Muscle Synergy Analysis

    Directory of Open Access Journals (Sweden)

    Xiang Chen

    2017-05-01

    Full Text Available To investigate the intra- and inter-limb muscle coordination mechanism of human hands-and-knees crawling by means of muscle synergy analysis, surface electromyographic (sEMG signals of 20 human adults were collected bilaterally from 32 limb related muscles during crawling with hands and knees at different speeds. The nonnegative matrix factorization (NMF algorithm was exerted on each limb to extract muscle synergies. The results showed that intra-limb coordination was relatively stable during human hands-and-knees crawling. Two synergies, one relating to the stance phase and the other relating to the swing phase, could be extracted from each limb during a crawling cycle. Synergy structures during different speeds kept good consistency, but the recruitment levels, durations, and phases of muscle synergies were adjusted to adapt the change of crawling speed. Furthermore, the ipsilateral phase lag (IPL value which was used to depict the inter-limb coordination changed with crawling speed for most subjects, and subjects using the no-limb-pairing mode at low speed tended to adopt the trot-like mode or pace-like mode at high speed. The research results could be well explained by the two-level central pattern generator (CPG model consisting of a half-center rhythm generator (RG and a pattern formation (PF circuit. This study sheds light on the underlying control mechanism of human crawling.

  4. Movement constraints on interpersonal coordination and communication.

    Science.gov (United States)

    Tolston, Michael T; Shockley, Kevin; Riley, Michael A; Richardson, Michael J

    2014-10-01

    The present study investigated how constraining movement affects interpersonal coordination and joint cognitive performance. Pairs of participants worked cooperatively to solve picture-puzzle tasks in which they conversed to identify differences between pictures in 3 degree-of-constraint conditions: both participants were free to move their hands (free-free; FF); both participants' hands were restrained (restrained-restrained; RR); and the hands of 1 participant were free while the hands of the other participant were restrained (free-restrained; FR). Eye tracking data were collected, and movement was measured at the waist, hand, and head. Data were analyzed using Cross-Recurrence Quantification Analysis (CRQ). Postural sway coordination, gaze coordination, and task performance were predicted to be highest in FF, followed by RR, and then by FR. Results showed the asymmetric FR condition generally exhibited lesser degrees of coordination than the symmetric Conditions FF and RR, and that the patterning of coordination in the symmetric conditions varied across the measured body segments. These results demonstrate that movement restraints affect not only interpersonal postural coordination, but also joint attention. Additionally, significant positive relationships were found between task performance and total amount of anterior-posterior movement measured at the head, hand and waist; number of utterances; and number of differences pairs found in the puzzles. These findings indicate a relationship between movement and task performance consistent with the hypotheses that both interpersonal coordination and cognitive performance are sensitive to local action constraints.

  5. Examining the Spatiotemporal Disruption to Gaze When Using a Myoelectric Prosthetic Hand.

    Science.gov (United States)

    Parr, J V V; Vine, S J; Harrison, N R; Wood, G

    2017-09-19

    The aim of this study was to provide a detailed account of the spatial and temporal disruptions to eye-hand coordination when using a prosthetic hand during a sequential fine motor skill. Twenty-one able-bodied participants performed 15 trials of the picking up coins task derived from the Southampton Hand Assessment Procedure with their anatomic hand and with a prosthesis simulator while wearing eye-tracking equipment. Gaze behavior results revealed that when using the prosthesis, performance detriments were accompanied by significantly greater hand-focused gaze and a significantly longer time to disengage gaze from manipulations to plan upcoming movements. The study findings highlight key metrics that distinguish disruptions to eye-hand coordination that may have implications for the training of prosthesis use.

  6. Children and older adults exhibit distinct sub-optimal cost-benefit functions when preparing to move their eyes and hands.

    Directory of Open Access Journals (Sweden)

    Claudia C Gonzalez

    Full Text Available Numerous activities require an individual to respond quickly to the correct stimulus. The provision of advance information allows response priming but heightened responses can cause errors (responding too early or reacting to the wrong stimulus. Thus, a balance is required between the online cognitive mechanisms (inhibitory and anticipatory used to prepare and execute a motor response at the appropriate time. We investigated the use of advance information in 71 participants across four different age groups: (i children, (ii young adults, (iii middle-aged adults, and (iv older adults. We implemented 'cued' and 'non-cued' conditions to assess age-related changes in saccadic and touch responses to targets in three movement conditions: (a Eyes only; (b Hands only; (c Eyes and Hand. Children made less saccade errors compared to young adults, but they also exhibited longer response times in cued versus non-cued conditions. In contrast, older adults showed faster responses in cued conditions but exhibited more errors. The results indicate that young adults (18-25 years achieve an optimal balance between anticipation and execution. In contrast, children show benefits (few errors and costs (slow responses of good inhibition when preparing a motor response based on advance information; whilst older adults show the benefits and costs associated with a prospective response strategy (i.e., good anticipation.

  7. Coordination of intrinsic and extrinsic hand muscle activity as a function of wrist joint angle during two-digit grasping.

    Science.gov (United States)

    Johnston, Jamie A; Bobich, Lisa R; Santello, Marco

    2010-04-26

    Fingertip forces result from the activation of muscles that cross the wrist and muscles whose origins and insertions reside within the hand (extrinsic and intrinsic hand muscles, respectively). Thus, tasks that involve changes in wrist angle affect the moment arm and length, hence the force-producing capabilities, of extrinsic muscles only. If a grasping task requires the exertion of constant fingertip forces, the Central Nervous System (CNS) may respond to changes in wrist angle by modulating the neural drive to extrinsic or intrinsic muscles only or by co-activating both sets of muscles. To distinguish between these scenarios, we recorded electromyographic (EMG) activity of intrinsic and extrinsic muscles of the thumb and index finger as a function of wrist angle during a two-digit object hold task. We hypothesized that changes in wrist angle would elicit EMG amplitude modulation of the extrinsic and intrinsic hand muscles. In one experimental condition we asked subjects to exert the same digit forces at each wrist angle, whereas in a second condition subjects could choose digit forces for holding the object. EMG activity was significantly modulated in both extrinsic and intrinsic muscles as a function of wrist angle (both p<0.05) but only for the constant force condition. Furthermore, EMG modulation resulted from uniform scaling of EMG amplitude across all muscles. We conclude that the CNS controlled both extrinsic and intrinsic muscles as a muscle synergy. These findings are discussed within the theoretical frameworks of synergies and common neural input across motor nuclei of hand muscles. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  8. Task-irrelevant expectation violations in sequential manual actions: Evidence for a “check-after-surprise” mode of visual attention and eye-hand decoupling

    Directory of Open Access Journals (Sweden)

    Rebecca Martina Foerster

    2016-11-01

    Full Text Available When performing sequential manual actions (e.g., cooking, visual information is prioritized according to the task determining where and when to attend, look, and act. In well-practiced sequential actions, long-term memory (LTM-based expectations specify which action targets might be found where and when. We have previously demonstrated (Foerster and Schneider, 2015b that violations of such expectations that are task-relevant (e.g., target location change cause a regression from a memory-based mode of attentional selection to visual search. How might task-irrelevant expectation violations in such well-practiced sequential manual actions modify attentional selection? This question was investigated by a computerized version of the number-connection test. Participants clicked on nine spatially-distributed numbered target circles in ascending order while eye movements were recorded as proxy for covert attention. Target’s visual features and locations stayed constant for 65 prechange-trials, allowing practicing the manual action sequence. Consecutively, a task-irrelevant expectation violation occurred and stayed for 20 change-trials. Specifically, action target number 4 appeared in a different font. In 15 reversion-trials, number 4 returned to the original font. During the first task-irrelevant change trial, manual clicking was slower and eye scanpaths were larger and contained more fixations. The additional fixations were mainly checking fixations on the changed target while acting on later targets. Whereas the eyes repeatedly revisited the task-irrelevant change, cursor-paths remained completely unaffected. Effects lasted for 2-3 change trials and did not reappear during reversion. In conclusion, an unexpected task-irrelevant change on a task-defining feature of a well-practiced manual sequence leads to eye-hand decoupling and a check-after-surprise mode of attentional selection.

  9. Hand Preferences for Coordinated Bimanual Actions in 777 Great Apes: Implications for the Evolution of Handedness in Hominins

    Science.gov (United States)

    Hopkins, William D.; Phillips, Kimberley A.; Bania, Amanda; Calcutt, Sarah E.; Gardner, Molly; Russell, Jamie; Schaeffer, Jennifer; Lonsdorf, Elizabeth V.; Ross, Stephen R.; Schapiro, Steven J.

    2011-01-01

    Whether or not nonhuman primates exhibit population-level handedness remains a topic of considerable scientific debate. Here, we examined handedness for coordinated bimanual actions in a sample of 777 great apes including chimpanzees, bonobos, gorillas, and orangutans. We found population-level right-handedness in chimpanzees, bonobos and gorillas, but left-handedness in orangutans. Directional biases in handedness were consistent across independent samples of apes within each genus. We suggest that, contrary to previous claims, population-level handedness is evident in great apes but differs among species as a result of ecological adaptations associated with posture and locomotion. We further suggest that historical views of nonhuman primate handedness have been too anthropocentric, and we advocate for a larger evolutionary framework for the consideration of handedness and other aspects of hemispheric specialization among primates. PMID:21334723

  10. Hand preferences for coordinated bimanual actions in 777 great apes: implications for the evolution of handedness in hominins.

    Science.gov (United States)

    Hopkins, William D; Phillips, Kimberley A; Bania, Amanda; Calcutt, Sarah E; Gardner, Molly; Russell, Jamie; Schaeffer, Jennifer; Lonsdorf, Elizabeth V; Ross, Stephen R; Schapiro, Steven J

    2011-05-01

    Whether or not nonhuman primates exhibit population-level handedness remains a topic of considerable scientific debate. Here, we examined handedness for coordinated bimanual actions in a sample of 777 great apes including chimpanzees, bonobos, gorillas, and orangutans. We found population-level right-handedness in chimpanzees, bonobos and gorillas, but left-handedness in orangutans. Directional biases in handedness were consistent across independent samples of apes within each genus. We suggest that, contrary to previous claims, population-level handedness is evident in great apes but differs among species as a result of ecological adaptations associated with posture and locomotion. We further suggest that historical views of nonhuman primate handedness have been too anthropocentric, and we advocate for a larger evolutionary framework for the consideration of handedness and other aspects of hemispheric specialization among primates. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Electromyographic activity of hand muscles in a motor coordination game: effect of incentive scheme and its relation with social capital.

    Directory of Open Access Journals (Sweden)

    Roberto Censolo

    Full Text Available BACKGROUND: A vast body of social and cognitive psychology studies in humans reports evidence that external rewards, typically monetary ones, undermine intrinsic motivation. These findings challenge the standard selfish-rationality assumption at the core of economic reasoning. In the present work we aimed at investigating whether the different modulation of a given monetary reward automatically and unconsciously affects effort and performance of participants involved in a game devoid of visual and verbal interaction and without any perspective-taking activity. METHODOLOGY/PRINCIPAL FINDINGS: Twelve pairs of participants were submitted to a simple motor coordination game while recording the electromyographic activity of First Dorsal Interosseus (FDI, the muscle mainly involved in the task. EMG data show a clear effect of alternative rewards strategies on subjects' motor behavior. Moreover, participants' stock of relevant past social experiences, measured by a specifically designed questionnaire, was significantly correlated with EMG activity, showing that only low social capital subjects responded to monetary incentives consistently with a standard rationality prediction. CONCLUSIONS/SIGNIFICANCE: Our findings show that the effect of extrinsic motivations on performance may arise outside social contexts involving complex cognitive processes due to conscious perspective-taking activity. More importantly, the peculiar performance of low social capital individuals, in agreement with standard economic reasoning, adds to the knowledge of the circumstances that makes the crowding out/in of intrinsic motivation likely to occur. This may help in improving the prediction and accuracy of economic models and reconcile this puzzling effect of external incentives with economic theory.

  12. On the origins of human handedness and language: a comparative review of hand preferences for bimanual coordinated actions and gestural communication in nonhuman primates.

    Science.gov (United States)

    Meguerditchian, Adrien; Vauclair, Jacques; Hopkins, William D

    2013-09-01

    Within the evolutionary framework about the origin of human handedness and hemispheric specialization for language, the question of expression of population-level manual biases in nonhuman primates and their potential continuities with humans remains controversial. Nevertheless, there is a growing body of evidence showing consistent population-level handedness particularly for complex manual behaviors in both monkeys and apes. In the present article, within a large comparative approach among primates, we will review our contribution to the field and the handedness literature related to two particular sophisticated manual behaviors regarding their potential and specific implications for the origins of hemispheric specialization in humans: bimanual coordinated actions and gestural communication. Whereas bimanual coordinated actions seem to elicit predominance of left-handedness in arboreal primates and of right-handedness in terrestrial primates, all handedness studies that have investigated gestural communication in several primate species have reported stronger degree of population-level right-handedness compared to noncommunicative actions. Communicative gestures and bimanual actions seem to affect differently manual asymmetries in both human and nonhuman primates and to be related to different lateralized brain substrates. We will discuss (1) how the data of hand preferences for bimanual coordinated actions highlight the role of ecological factors in the evolution of handedness and provide additional support the postural origin theory of handedness proposed by MacNeilage [MacNeilage [2007]. Present status of the postural origins theory. In W. D. Hopkins (Ed.), The evolution of hemispheric specialization in primates (pp. 59-91). London: Elsevier/Academic Press] and (2) the hypothesis that the emergence of gestural communication might have affected lateralization in our ancestor and may constitute the precursors of the hemispheric specialization for language.

  13. Stopping eyes and hands: Evidence for non-independence of stop and go processes and for a separation of central and peripheral inhibition

    Directory of Open Access Journals (Sweden)

    Alessandro eGulberti

    2014-02-01

    Full Text Available In the stop-signal paradigm, participants perform a primary reaction task, for example a visual or auditory discrimination task, and have to react to a go stimulus as quickly as possible with a specified motor response. In a certain percentage of trials, after presentation of the stimulus (go signal, another stimulus (stop signal is presented with a variable stop-signal delay. Whenever a stop signal occurs, the participant is asked to inhibit the execution of the response. Here, an extended test of the popular horse race model for this task (Logan and Cowan 1984 is presented. Responses for eye and hand movements in both single-task and dual-task conditions were collected. Saccadic reaction times revealed some significant violations of the model's basic assumption of independent go and inhibition processes for all six participants. Saccades that escaped an early stop signal were systematically slower and had smaller amplitudes compared to saccades without a stop signal. Moreover, the analysis of concomitant electromyographic responses recorded from the upper arm suggests the existence of two separate inhibitory mechanisms: a slow, selective, central inhibitory mechanism and a faster, highly efficient, peripheral one, which is probably ineffective for saccades.

  14. EYE GAZE TRACKING

    DEFF Research Database (Denmark)

    2011-01-01

    This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of: detecting the position of at least three reflections on said eye, transforming said positions to spanning...... a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation, detecting the position of said center of the eye relative to the position...... of said reflections and transforming this position to said normalized coordinate system, tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system. Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided...

  15. Quantifying linguistic coordination

    DEFF Research Database (Denmark)

    Fusaroli, Riccardo; Tylén, Kristian

    task (Bahrami et al 2010, Fusaroli et al. 2012) we extend to linguistic coordination dynamical measures of recurrence employed in the analysis of sensorimotor coordination (such as heart-rate (Konvalinka et al 2011), postural sway (Shockley 2005) and eye-movements (Dale, Richardson and Kirkham 2012...... of linguistic coordination and their effects at a fine-degree....

  16. Arm-eye coordination test to objectively quantify motor performance and muscles activation in persons after stroke undergoing robot-aided rehabilitation training: a pilot study.

    Science.gov (United States)

    Song, Rong; Tong, Kai-Yu; Hu, Xiaoling; Li, Le; Sun, Rui

    2013-09-01

    This study designed an arm-eye coordination test to investigate the effectiveness of the robot-aided rehabilitation for persons after stroke. Six chronic poststroke subjects were recruited to attend a 20-session robot-aided rehabilitation training of elbow joint. Before and after the training program, subjects were asked to perform voluntary movements of elbow flection and extension by following sinusoidal trajectories at different velocities with visual feedback on their joint positions. The elbow angle and the electromyographic signal of biceps and triceps as well as clinical scores were evaluated together with the parameters. Performance was objectively quantified by root mean square error (RMSE), root mean square jerk (RMSJ), range of motion (ROM), and co-contraction index (CI). After 20 sessions, RMSE and ROM improved significantly in both the affected and the unaffected side based on two-way ANOVA (P < 0.05). There was significant lower RMSJ in the affected side at higher velocities (P < 0.05). There was significant negative correlation between average RMSE with different tracking velocities and Fugl-Meyer shoulder-elbow score (P < 0.05). There was also significant negative correlation between average RMSE and average ROM (P < 0.05), and moderate nonsignificant negative correlation with RMSJ, and CI. The characterization of velocity-dependent deficiencies, monitoring of training-induced improvement, and the correlation between quantitative parameters and clinical scales could enable the exploration of effects of different types of treatment and design progress-based training method to accelerate the processes of recovery.

  17. The relationship between segmental coordination, agility and physical activity in adolescents

    Directory of Open Access Journals (Sweden)

    Eliseo García Cantó

    2015-06-01

    Full Text Available Motor competence (MC may be related to youth physical activity (PA level. In the last few years, MC has been studied as a possible determinant of children PA level, but has not been widely studied in adolescents. To analyze the relationship between MC and PA level 533 adolescents (271 men and 261 women from the southeast of Spain were assessed. To register weekly PA was used the International Physical Activity Questionnaire (IPAQ and for the MC, four coordination tests including throw and catch test, eye-hand and eye-foot coordination tests and agility circuit. Data were analyzed using ANOVA and binary logistic regression. The overall MC is consistently related with PA level. Eye-hand coordination test and the agility test define more accurately the tendency to high PA level. Programs to promote PA and focused on MC should be emphasized from early ages to adolescence.

  18. Left, right, left, right, eyes to the front! Müller-Lyer bias in grasping is not a function of hand used, hand preferred or visual hemifield, but foveation does matter.

    NARCIS (Netherlands)

    van der Kamp, J.; de Wit, M.M.; Masters, R.S.W.

    2012-01-01

    We investigated whether the control of movement of the left hand is more likely to involve the use of allocentric information than movements performed with the right hand. Previous studies (Gonzalez et al. in J Neurophys 95:3496-3501, 2006; De Grave et al. in Exp Br Res 193:421-427, 2009) have

  19. Handedness for Unimanual Grasping in 564 Great Apes: The Effect on Grip Morphology and a Comparison with Hand Use for a Bimanual Coordinated Task

    Directory of Open Access Journals (Sweden)

    Adrien eMeguerditchian

    2015-11-01

    Full Text Available A number of factors have been proposed to influence within and between species variation in handedness in nonhuman primates. In the initial study, we assessed the influence of grip morphology on hand use for simple reaching in a sample of 564 great apes including 49 orangutans Pongo pygmaeus, 66 gorillas Gorilla gorilla, 354 chimpanzees Pan troglodytes and 95 bonobos Pan paniscus. Overall, we found a significant right hand bias for reaching. We also found a significant effect of the grip morphology of hand use. Grasping with the thumb and index finger was more prevalent in the right compared to left hand in all 4 species. There was no significant sex effect on the patterns of handedness. In a subsample of apes, we also compared consistency in hand use for simple reaching with previously published data on a task that measures handedness for bimanual actions. We found that the ratio of subjects with consistent right compared to left hand use was more prevalent in bonobos, chimpanzees and gorillas but not orangutans. However, for all species, the proportion of subjects with inconsistent hand preferences between the tasks was relatively high suggesting some measures may be more sensitive in assessing handedness than others.

  20. Eye Allergies

    Science.gov (United States)

    ... Stories Español Eye Health / Eye Health A-Z Eye Allergies Sections What Are Eye Allergies? Eye Allergy ... Eye allergy diagnosis Eye allergy treatment What Are Eye Allergies? Leer en Español: ¿Qué Son las Alergias ...

  1. Magnetic eye tracking in mice.

    Science.gov (United States)

    Payne, Hannah L; Raymond, Jennifer L

    2017-09-05

    Eye movements provide insights about a wide range of brain functions, from sensorimotor integration to cognition; hence, the measurement of eye movements is an important tool in neuroscience research. We describe a method, based on magnetic sensing, for measuring eye movements in head-fixed and freely moving mice. A small magnet was surgically implanted on the eye, and changes in the magnet angle as the eye rotated were detected by a magnetic field sensor. Systematic testing demonstrated high resolution measurements of eye position of eye tracking offers several advantages over the well-established eye coil and video-oculography methods. Most notably, it provides the first method for reliable, high-resolution measurement of eye movements in freely moving mice, revealing increased eye movements and altered binocular coordination compared to head-fixed mice. Overall, magnetic eye tracking provides a lightweight, inexpensive, easily implemented, and high-resolution method suitable for a wide range of applications.

  2. Eye redness

    Science.gov (United States)

    Bloodshot eyes; Red eyes; Scleral injection; Conjunctival injection ... There are many causes of a red eye or eyes. Some are medical emergencies. Others are a cause for concern, but not an emergency. Many are nothing to worry about. Eye ...

  3. Prevalência da dissociação óculo-manual em crianças com dislexia do desenvolvimento = Prevalence of eye-hand preference dissociation in childrens with development dyslexia

    Directory of Open Access Journals (Sweden)

    Marielza Regina Ismael Martins

    2012-01-01

    Full Text Available A presente pesquisa caracterizou-se em determinar a prevalência da dissociação ocular e manual em crianças com dislexia do desenvolvimento em idade escolar comparadas com crianças normais, pertencentes a escolas públicas. Participaram do estudo crianças entre sete e 12 anos. O Grupo I foi constituído por crianças diagnosticadas com dislexia do desenvolvimento (n = 64 e o Grupo II constituído por crianças- padrão na mesma faixa etária (n = 80. Foi aplicada a Bateria Psicomotora. As crianças disléxicas obtiveram escores significativos de prevalência manual esquerda e ocular direita. Tais resultados sugerem que esta falta de especialização da lateralidade pode comprometer a execução motora.This research was characterized to determine the prevalence of dissociation eye and hand in children with developmental dyslexia at school age compared with normal children from public schools. Study participants were children between seven and 12 years. Group I consisted of children diagnosed with developmental dyslexia (n = 64 and Group II consists of standard children the same age (n = 80. Psychomotor Battery was applied. Dyslexic children scored significant prevalence of left hand and right eye. These results suggest that this lack of expertise of laterality may impair motor execution.

  4. From the Gleam in the Eye of an Engineer to a Dream Classroom: How Assistive Technology Products Move from Research and Development into the Hands of Children

    Science.gov (United States)

    de St. Aubin, Shawn-Laree

    2010-01-01

    This article explains how Asssistive Technology products move from research and development into the hands of children. The assistive technology (AT) industry is maturing, with many exciting new technologies under development in university settings, by individual inventors and engineers, and by leading AT and information technology (IT) companies.…

  5. Eye cosmetics.

    Science.gov (United States)

    Draelos, Z K

    1991-01-01

    Eye cosmetics are useful to highlight and emphasize the eyes. Currently available eye cosmetics include eye shadows, eye shadow setting creams, under-eye concealers, eye-liners, mascaras, artificial eyelashes, and eyebrow pencils. Special care must be taken when patients with sensitive skin or contact lens wearers select eye cosmetics. Eye cosmetics may also be the cause of either irritant or allergic contact dermatitis, which are two causes of the upper-eyelid dermatitis syndrome.

  6. It's in the eyes: Planning precise manual actions before execution.

    Science.gov (United States)

    Belardinelli, Anna; Stepper, Madeleine Y; Butz, Martin V

    2016-01-01

    It is well-known that our eyes typically fixate those objects in a scene, with which interactions are about to unfold. During manual interactions, our eyes usually anticipate the next subgoal and thus serve top-down, goal-driven information extraction requirements, probably driven by a schema-based task representation. On the other hand, motor control research concerning object manipulations has extensively demonstrated how grasping choices are often influenced by deeper considerations about the final goal of manual interactions. Here we show that also these deeper considerations are reflected in early eye fixation behavior, significantly before the hand makes contact with the object. In this study, subjects were asked to either pretend to drink out of the presented object or to hand it over to the experimenter. The objects were presented upright or upside down, thus affording a thumb-up (prone) or a thumb-down (supine) grasp. Eye fixation data show a clear anticipatory preference for the region where the index finger is going to be placed. Indeed, fixations highly correlate with the final index finger position, thus subserving the planning of the actual manual action. Moreover, eye fixations reveal several orders of manual planning: Fixation distributions do not only depend on the object orientation but also on the interaction task. These results suggest a fully embodied, bidirectional sensorimotor coupling of eye-hand coordination: The eyes help in planning and determining the actual manual object interaction, considering where to grasp the presented object in the light of the orientation and type of the presented object and the actual manual task to be accomplished with the object.

  7. Hand collection - hand harvest

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of activities related to the collection and harvest of seeds on Neal Smith National Wildlife Refuge between 1992 and 2009. Information about hand...

  8. Hand Therapy

    Science.gov (United States)

    ... Therapist? Media Find a Hand Surgeon Home Anatomy Hand Therapy Email to a friend * required fields From * ... ensure a healthy style of work. Find a Hand Therapist Search for a hand therapist in your ...

  9. 'Always the guiding hand': parents' accounts of the long-term implications of developmental co-ordination disorder for their children and families.

    Science.gov (United States)

    Stephenson, E A; Chesson, R A

    2008-05-01

    There has been little investigation of the long-term implications of developmental co-ordination disorder (DCD) and, particularly, its impact on families. This is despite the prevalence of the disorder (4.5% to 6%) of the child population, and the high rates of referral to occupational therapy departments. The study reported here was part of an evaluation of an innovative screening clinic for the assessment of children with DCD. Within the case study approach of the evaluation, questionnaires, including open-end questions, were sent to 70 families. All had attended the screening clinic 6 years earlier and had little subsequent contact with the occupational therapy service. Semi-structured interviews were held with 12 mothers who volunteered to participate. These enabled specific issues raised in the questionnaires to be explored in greater depth. Interviews were audiotaped and full text transcripts produced for analysis. Over half the questionnaires were returned despite the length of time elapsed since hospital contact. Parents who responded reported a high persistence of problems in their children. Difficulties spanned motor and academic performance, emotional/behavioural responses and social interaction. Twenty-eight children (80%) of respondents were reported as having difficulties in three or more areas. Bullying was a commonly identified problem. At interview mothers spoke at length about their experiences and reported feeling stressed and distressed. Mothers reported a lack of support and expressed feelings of isolation. They said that their time investment in their child with DCD had pronounced effects on themselves and other family members. Specifically they highlighted time spent fighting the system, primarily for educational support. The study suggests a need for occupational therapists to reframe their current ideas regarding service provision, with improved support for families, increased interagency working and more service-user involvement.

  10. Dextrous robot hands

    Science.gov (United States)

    Venkataraman, Subramanian T. (Editor); Iberall, Thea (Editor)

    1990-01-01

    Recent studies of human hand function and their implications for the design of robot hands are discussed in reviews and reports. Topics addressed include human grasp choice and robotic grasp analysis, opposition space and human prehension, coordination in normal and prosthetic reaching, and intelligent exploration by the human hand. Consideration is given to a task-oriented dextrous manipulation architecture, the control architecture for the Belgrade/USC hand, the analysis of multifingered grasping and manipulation, and tactile sensing for shape interpretation. Diagrams, graphs, and photographs are provided.

  11. THE INFLUENCE OF THE EXERCISES OF GROSS AND FINE MOTOR SKILLS ON VISUO-MOTOR COORDINATION OF THE CEREBRAL PALSY CHILDREN

    Directory of Open Access Journals (Sweden)

    Almira Mujkić

    2013-09-01

    Full Text Available Visuomotor coordination is reffered to eye coordination and to various parts of the body in different activities and games. The aim of the research was to establish the influence of the exercises of gross and fine motor skills on visuomotor coordination of the cerebral palsy children. The sample was the case study where a male person of 3 and a half years old was an examinee. Measuring instrument used was the Test of visuomotor coordination of the gross motor skills of the dominant hand. Data were analyzed by t-test.

  12. Eye Wear

    Science.gov (United States)

    Eye wear protects or corrects your vision. Examples are Sunglasses Safety goggles Glasses (also called eyeglasses) Contact ... jobs and some sports carry a risk of eye injury. Thousands of children and adults get eye ...

  13. Eye Cancer

    Science.gov (United States)

    Cancer of the eye is uncommon. It can affect the outer parts of the eye, such as the eyelid, which are made up ... adults are melanoma and lymphoma. The most common eye cancer in children is retinoblastoma, which starts in ...

  14. Eye Injuries

    Science.gov (United States)

    ... of your face helps protect your eyes from injury. Still, injuries can damage your eye, sometimes severely enough that you could lose your vision. Most eye injuries are preventable. If you play sports or work ...

  15. Eye emergencies

    Science.gov (United States)

    ... Keep flushing the eye with clean water or saline for at least 15 minutes. Seek medical help right away. Do not delay. EYE CUT, SCRATCH, OR BLOW Gently apply a clean cold compress to the eye to reduce swelling and ...

  16. Eye-hand preference dissociation in obsessive-compulsive disorder and dyslexia Dissociação da preferência ocular e manual em pacientes com transtorno obsessivo-compulsivo e dislexia

    Directory of Open Access Journals (Sweden)

    Marilena Occhini Siviero

    2002-06-01

    Full Text Available Dyslexia may be a development disturbance in which there are alterations in visual-spatial and visual-motor processing, while obsessive-compulsive disorder (OCD is a psychiatric disease in which there are alterations in memory, executive function, and visual-spatial processing. Our hypothesis is that these disturbances may be, at least partially, the result of a crossed eye and hand preference. In the present study 16 controls, 20 OCD (DSM-IV criteria and 13 dyslexic adults (Brazilian Dyslexia Association criteria were included. All had a neurological examination, the Yale-Brown scale for obsessive-compulsive symptoms application and the Zazzó evaluation for laterality, abridged by Granjon. Results showed a right hand preference for 100% of controls, 84.6% of dyslexics, and 75% of OCD patients and a right eye preference for 73.3% of controls, 69.2% of dyslexics, and 35% of OCD patients. The left eye preference was significantly higher in OCD when compared with the two other groups (p = 0.01 and the left hand preference of OCD patients (25% was also significant when compared to Brazilian population (4% or British population (4.5%. It is possible that this crossed preference may be partially the reason for visual-spatial and constructive disturbances observed in OCD.A dislexia pode resultar de distúrbio do desenvolvimento e apresenta alterações no processamento visuo-espacial e visuo-motor, enquanto o transtorno obsessivo compulsivo (TOC é uma alteração psiquiátrica na qual podem ocorrer alterações de memória, função executiva e visuo-espacial. Nossa hipótese é que parte destes distúrbios pode decorrer da preferência ocular e manual cruzadas. Foram avaliados 16 indivíduos normais, 20 pacientes com TOC, (critérios da DSM-IV e 13 adultos disléxicos (critérios da Associação Brasileira de Dislexia. Todos passaram por exame neurológico, avaliação de sintomas obsessivos-compulsivos pela escala Yale-Brown e pela bateria para

  17. Hand Anatomy

    Science.gov (United States)

    ... Arthritis Thumb Sprains Trigger Finger Tumors Wrist Fracture Hand Safety Fireworks Safety Lawnmower Safety Snowblower safety Pumpkin ... A-Z Videos Infographics Symptom Picker Anatomy About Hand Surgery What is a Hand Surgeon? What is ...

  18. Claw hand

    Science.gov (United States)

    Ulnar nerve palsy - claw hand; Ulnar nerve dysfunction - claw hand; Ulnar claw ... Someone can be born with claw hand (congenital), or they can develop it because of certain disorders, such as nerve injury.

  19. Modeling the Scheduling of Eye Movements and Manual Responses in Performing a Sequence of Discrete Tasks

    Science.gov (United States)

    Wu, Shu-Chieh; Remington, Roger W.; Lewis, Richard

    2006-01-01

    Common tasks in daily life are often accomplished by a sequence of actions that interleave information acquisition through the eyes and action execution by the hands. How are eye movements coordinated with the release of manual responses and how may their coordination be represented at the level of component mental operations? We have previously presented data from a typing-like task requiring separate choice responses to a series of five stimuli. We found a consistent pattern of results in both motor and ocular timing, and hypothesized possible relationships among underlying components. Here we report a model of that task, which demonstrates how the observed timing of eye movements to successive stimuli could be accounted for by assuming systems: an open-loop system generating saccades at a periodic rate, and a closed-loop system commanding a saccade based on stimulus processing. We relate this model to models of reading and discuss the motivation for dual control.

  20. Smooth pursuit eye movement preferentially facilitates motor-evoked potential elicited by anterior-posterior current in the brain.

    Science.gov (United States)

    Hiraoka, Koichi; Ae, Minori; Ogura, Nana; Komuratani, Sayo; Sano, Chisa; Shiomi, Keigo; Morita, Yuji; Yokoyama, Haruka

    2014-03-26

    Neural interaction between the eye and hand movement centers must be a critical part of the mechanism underlying eye-hand coordination. One of the previous findings supporting this view is smooth pursuit eye movement-induced suppression of motor-evoked potential (MEP) in the hand muscles. The purpose of this study was to determine which descending volleys contributing to MEP are preferentially modulated by smooth pursuit eye movement. MEP in the first dorsal interosseous muscle was elicited by different directions of current in the brain during the steady-state phase of smooth pursuit eye movement. Smooth pursuit eye movement facilitated MEP elicited by anterior-posterior (AP) current, but this effect was not seen in MEP elicited by lateromedial or posterior-anterior current. Latency of MEP elicited by AP current was significantly longer than latencies of MEPs elicited by other directions of current, indicating that AP current in the brain predominantly elicited later I-waves. We conclude that smooth pursuit eye movement in the steady-state phase preferentially facilitates MEP predominantly elicited by later I-waves generated by AP current in the brain.

  1. Android Hands

    DEFF Research Database (Denmark)

    Vlachos, Evgenios; Schärfe, Henrik

    2014-01-01

    . On such occasions, android and humanoid hand models should have similar structure, functions, and performance as the human hand. In this paper we present the anatomy, and the key functionalities of the human hand followed by a literature review on android/humanoid hands for grasping and manipulating objects...

  2. Fixational eye movements and binocular vision.

    Science.gov (United States)

    Otero-Millan, Jorge; Macknik, Stephen L; Martinez-Conde, Susana

    2014-01-01

    During attempted visual fixation, small involuntary eye movements-called fixational eye movements-continuously change of our gaze's position. Disagreement between the left and right eye positions during such motions can produce diplopia (double vision). Thus, the ability to properly coordinate the two eyes during gaze fixation is critical for stable perception. For the last 50 years, researchers have studied the binocular characteristics of fixational eye movements. Here we review classical and recent studies on the binocular coordination (i.e., degree of conjugacy) of each fixational eye movement type: microsaccades, drift and tremor, and its perceptual contribution to increasing or reducing binocular disparity. We also discuss how amblyopia and other visual pathologies affect the binocular coordination of fixational eye movements.

  3. Eye Cancer

    Science.gov (United States)

    ... form of childhood eye cancer. Hemangioma is a benign tumor of the choroid and retina that starts in the blood vessels. Other, rare cancers of the eye include: Conjunctival melanoma is a tumor of the conjunctiva, which is ...

  4. Eye Anatomy

    Science.gov (United States)

    ... News About Us Donate In This Section Eye Anatomy en Español email Send this article to a ... You at Risk For Glaucoma? Childhood Glaucoma Eye Anatomy Five Common Glaucoma Tests Glaucoma Facts and Stats ...

  5. [Hand osteoarthritis].

    Science.gov (United States)

    Šenolt, Ladislav

    Hand osteoarthritis (OA) is a common chronic disorder causing pain and limitation of mobility of affected joints. The prevalence of hand OA increases with age and more often affects females. Clinical signs obviously do not correlate with radiographic findings - symptomatic hand OA affects approximately 26 % of adult subjects, but radiographic changes can be found in up to two thirds of females and half of males older than 55 years.Disease course differ among individual patients. Hand OA is a heterogeneous disease. Nodal hand OA is the most common subtype affecting interphalangeal joints, thumb base OA affects first carpometacarpal joint. Erosive OA represents a specific subtype of hand OA, which is associated with joint inflammation, more pain, functional limitation and erosive findings on radiographs.Treatment of OA is limited. Analgesics and nonsteroidal anti-inflammatory drugs are the only agents reducing symptoms. New insights into the pathogenesis of disease should contribute to the development of novel effective treatment of hand OA.

  6. Monocular tool control, eye dominance, and laterality in New Caledonian crows.

    Science.gov (United States)

    Martinho, Antone; Burns, Zackory T; von Bayern, Auguste M P; Kacelnik, Alex

    2014-12-15

    Tool use, though rare, is taxonomically widespread, but morphological adaptations for tool use are virtually unknown. We focus on the New Caledonian crow (NCC, Corvus moneduloides), which displays some of the most innovative tool-related behavior among nonhumans. One of their major food sources is larvae extracted from burrows with sticks held diagonally in the bill, oriented with individual, but not species-wide, laterality. Among possible behavioral and anatomical adaptations for tool use, NCCs possess unusually wide binocular visual fields (up to 60°), suggesting that extreme binocular vision may facilitate tool use. Here, we establish that during natural extractions, tool tips can only be viewed by the contralateral eye. Thus, maintaining binocular view of tool tips is unlikely to have selected for wide binocular fields; the selective factor is more likely to have been to allow each eye to see far enough across the midsagittal line to view the tool's tip monocularly. Consequently, we tested the hypothesis that tool side preference follows eye preference and found that eye dominance does predict tool laterality across individuals. This contrasts with humans' species-wide motor laterality and uncorrelated motor-visual laterality, possibly because bill-held tools are viewed monocularly and move in concert with eyes, whereas hand-held tools are visible to both eyes and allow independent combinations of eye preference and handedness. This difference may affect other models of coordination between vision and mechanical control, not necessarily involving tools. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Hand eczema

    DEFF Research Database (Denmark)

    Ibler, K.S.; Jemec, G.B.E.; Flyvholm, M.-A.

    2012-01-01

    Background. Healthcare workers are at increased risk of developing hand eczema. Objectives. To investigate the prevalence and severity of self-reported hand eczema, and to relate the findings to demographic data, occupation, medical speciality, wards, shifts, and working hours. Patients....../materials/methods. A survey of 3181 healthcare workers was performed. Data were analysed with logistic regression. Data on sick leave and notification to the authorities were obtained. Results. The response rate was 71% (2274 of 3181). The 1-year prevalence of hand eczema was 21%, and was positively associated with atopic....... The 21% prevalence of hand eczema in healthcare workers is double the prevalence in the background population. Eleven per cent of hand eczema patients reported severe/very severe eczema. No significant differences were found between professions or medical specialities with respect to prevalence...

  8. Management of pediatric hand burns.

    Science.gov (United States)

    Liodaki, Eirini; Kisch, Tobias; Mauss, Karl L; Senyaman, Oezge; Kraemer, Robert; Mailänder, Peter; Wünsch, Lutz; Stang, Felix

    2015-04-01

    Hand burns are common in the pediatric population. Optimal hand function is a crucial component of a high-quality survival after burn injury. This can only be achieved with a coordinated approach to the injuries. The aim of this study was to review the management algorithm and outcomes of pediatric hand burns at our institution. In total, 70 children fulfilling our study criteria were treated for a burn hand injury in our Burn Care Center between January 2008 and May 2013. 14 of the 70 pediatric patients underwent surgery because of the depth of the hand burns. The management algorithm depending on the depth of the burn is described. Two patients underwent correction surgery due to burn contractures later. For a successful outcome of the burned hand, the interdisciplinary involvement and cooperation of the plastic and pediatric surgeon, hand therapist, burn team, patient and their parents are crucial.

  9. Binocular coordination in response to stereoscopic stimuli.

    OpenAIRE

    Liversedge, S.P.; Holliman, N. S.; Blythe, H.I.

    2009-01-01

    Humans actively explore their visual environment by moving their eyes. Precise coordination of the eyes during visual scanning underlies the experience of a unified perceptual representation and is important for the perception of depth. We report data from three psychological experiments investigating human binocular coordination during visual processing of stereoscopic stimuli.In the first experiment participants were required to read sentences that contained a stereoscopically presented tar...

  10. Mixed Body/Hand Reference Frame for Reaching in 3D Space in Macaque Parietal Area PEc.

    Science.gov (United States)

    Piserchia, Valentina; Breveglieri, Rossella; Hadjidimitrakis, Kostas; Bertozzi, Federica; Galletti, Claudio; Fattori, Patrizia

    2017-03-01

    The neural correlates of coordinate transformations from vision to action are expressed in the activity of posterior parietal cortex (PPC). It has been demonstrated that among the medial-most areas of the PPC, reaching targets are represented mainly in hand-centered coordinates in area PE, and in eye-centered, body-centered, and mixed body/hand-centered coordinates in area V6A. Here, we assessed whether neurons of area PEc, located between V6A and PE in the medial PPC, encode targets in body-centered, hand-centered, or mixed frame of reference during planning and execution of reaching. We studied 104 PEc cells in 3 Macaca fascicularis. The animals performed a reaching task toward foveated targets located at different depths and directions in darkness, starting with the hand from 2 positions located at different depths, one next to the trunk and the other far from it. We show that most PEc neurons encoded targets in a mixed body/hand-centered frame of reference. Although the effect of hand position was often rather strong, it was not as strong as reported previously in area PE. Our results suggest that area PEc represents an intermediate node in the gradual transformation from vision to action that takes place in the reaching network of the dorsomedial PPC. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Bimanual coordination in dyslexic adults.

    Science.gov (United States)

    Moore, L H; Brown, W S; Markee, T E; Theberge, D C; Zvi, J C

    1995-06-01

    Various types of dyslexia have been associated with tactile-motor coordination deficits and inefficient transfer of information between the two cerebral hemispheres. Twenty-one dyslexic adults were compared to 21 controls on the Bimanual Coordination Task, a test of tactile-motor coordination and interhemispheric collaboration. When compared to control subjects, dyslexics showed a consistent pattern of deficits in bimanual motor coordination, both with and without visual feedback. In particular, dyslexics had greater difficulty relative to normals when the left hand had to move faster than the right, and when the hands had to make opposite (mirror-image) movements, suggesting problems with interhemispheric modulation of visuomotor control. In addition, accuracy on this bimanual coordination task was significantly correlated with the Block Design subtest of the WAIS--R, but not with a rhyme fluency task, suggesting some contribution of right hemisphere controlled visuospatial skill to performance.

  12. Robotic Hand

    Science.gov (United States)

    1993-01-01

    The Omni-Hand was developed by Ross-Hime Designs, Inc. for Marshall Space Flight Center (MSFC) under a Small Business Innovation Research (SBIR) contract. The multiple digit hand has an opposable thumb and a flexible wrist. Electric muscles called Minnacs power wrist joints and the interchangeable digits. Two hands have been delivered to NASA for evaluation for potential use on space missions and the unit is commercially available for applications like hazardous materials handling and manufacturing automation. Previous SBIR contracts resulted in the Omni-Wrist and Omni-Wrist II robotic systems, which are commercially available for spray painting, sealing, ultrasonic testing, as well as other uses.

  13. Ocular surface area and human eye blink frequency during VDU work

    DEFF Research Database (Denmark)

    Nielsen, Pernille Kofoed; Søgaard, Karen; Skotte, Jørgen

    2008-01-01

    The purpose of this study was to investigate how the ocular surface area (OSA) and the eye blink frequency (BF) are affected by a high versus a low-monitor position during visual display unit (VDU) work with varying cognitive demands. In a balanced randomized (2 x 2) design ten healthy subjects...... (five males, five females) completed two different tasks on the VDU in a simulated office environment (23 degrees C and 30-35% relative humidity); an active task with demands on vision and hand-eye coordination, and a passive task. Two monitor positions were used: high (the monitors' upper edge...... at the same height as the subjects' eyes) and low (lowered by 25 degrees and perpendicular to gaze angle). Each task lasted 10 min. An OSA-proxy was measured from video recordings, and BF was sampled by electrooculography. The effect of lowering the gaze angle by 25 degrees decreased the OSA...

  14. Diabetes eye exams

    Science.gov (United States)

    Diabetic retinopathy - eye exams; Diabetes - eye exams; Glaucoma - diabetic eye exam; Macular edema - diabetic eye exam ... if the doctor who takes care of your diabetes checks your eyes, you need an eye exam ...

  15. Hand Eczema

    Science.gov (United States)

    Agarwal, Uma Shankar; Besarwal, Raj Kumar; Gupta, Rahul; Agarwal, Puneet; Napalia, Sheetal

    2014-01-01

    Hand eczema is often a chronic, multifactorial disease. It is usually related to occupational or routine household activities. Exact etiology of the disease is difficult to determine. It may become severe enough and disabling to many of patients in course of time. An estimated 2-10% of population is likely to develop hand eczema at some point of time during life. It appears to be the most common occupational skin disease, comprising 9-35% of all occupational diseases and up to 80% or more of all occupational contact dermatitis. So, it becomes important to find the exact etiology and classification of the disease and to use the appropriate preventive and treatment measures. Despite its importance in the dermatological practice, very few Indian studies have been done till date to investigate the epidemiological trends, etiology, and treatment options for hand eczema. In this review, we tried to find the etiology, epidemiology, and available treatment modalities for chronic hand eczema patients. PMID:24891648

  16. Toward an Epistemology of the Hand

    DEFF Research Database (Denmark)

    Brinkmann, Svend; Tanggaard, Lene

    2010-01-01

    ‘epistemology of the eye' has been at work, which has had significant practical implications, not least in educational contexts. One way to characterize John Dewey's pragmatism is to see it as an attempt to replace the epistemology of the eye with an epistemology of the hand. This article develops...

  17. Tuberculosis; Eye

    African Journals Online (AJOL)

    muscle could present as a painful swelling over the corresponding part of the eye with associated restriction of ocular motility involving the muscle. TUBERCULOSIS OF THE EYE. CORNEA: Primary infection of the cornea is very rare. Corneal involvement is usually due to a hypersentitivity or cross-reaction whereby the.

  18. Eye cosmetics.

    Science.gov (United States)

    O'Donoghue, M N

    2000-10-01

    There are many eye cosmetics available to enhance the beauty or improve the appearance of the face. To prevent infection, most eye cosmetics contain preservatives. Fragrance is usually absent to keep the products as safe as possible. Hypoallergenic products contain fewer ingredients and may be more appropriate for patients with sensitive skin.

  19. Different hands

    NARCIS (Netherlands)

    dr. H.A.M. van Lieshout

    2008-01-01

    This book is about markets for intermediate skills. It is also about the coordination within and between the (vocational) education system and the (sub-baccalaureate) labor market, and the institutions that govern them. Our goal was to improve our understanding of how particular governance regimes

  20. Hand Eczema

    OpenAIRE

    Uma Shankar Agarwal; Raj Kumar Besarwal; Rahul Gupta; Puneet Agarwal; Sheetal Napalia

    2014-01-01

    Hand eczema is often a chronic, multifactorial disease. It is usually related to occupational or routine household activities. Exact etiology of the disease is difficult to determine. It may become severe enough and disabling to many of patients in course of time. An estimated 2-10% of population is likely to develop hand eczema at some point of time during life. It appears to be the most common occupational skin disease, comprising 9-35% of all occupational diseases and up to 80% or more of ...

  1. In a demanding task, three-handed manipulation is preferred to two-handed manipulation

    OpenAIRE

    Elahe Abdi; Etienne Burdet; Mohamed Bouri; Sharifa Himidan; Hannes Bleuler

    2016-01-01

    Equipped with a third hand under their direct control, surgeons may be able to perform certain surgical interventions alone; this would reduce the need for a human assistant and related coordination difficulties. However, does human performance improve with three hands compared to two hands? To evaluate this possibility, we carried out a behavioural study on the performance of naive adults catching objects with three virtual hands controlled by their two hands and right foot. The subjects cou...

  2. Risk factors, incidence and persistence of symptoms from the eyes among professional computer users.

    Science.gov (United States)

    Toomingas, A; Hagberg, M; Heiden, M; Richter, H; Westergren, K E; Tornqvist, E Wigaeus

    2014-01-01

    Symptoms from the eyes are common among computer users. Knowledge is scarce about these problems, however. The aim was to study risk-factors, incidence and persistence of eye-symptoms among professionally active computer users. This was a questionnaire based prospective study where 1283 males and females from different professions and companies answered a baseline questionnaire about individual factors and working conditions, e.g. duration of daily computer work, comfort of screen work, psychosocial factors. Subjects were at baseline and 10 follow-ups asked about the number of days with eye-symptoms during the preceding month. The incidence-rate of symptoms persisting minimum three days was 0.38/person-year. A multivariate Hazard-ratio model showed significant associations with extended continuous computer work, tasks with high demands on eye-hand coordination, low level of control, visual discomfort, female sex and nicotine use. Eye-symptoms at baseline was a strong risk factor for new symptoms. The incidence of eye-symptoms among professional computer users is high and related to both individual and work-related factors. The organization of computer work should secure frequent breaks from near-work at the computer screen. The severity of vision-related problems could in field studies be quantified by asking for the persistence of symptoms.

  3. Red Eye

    Science.gov (United States)

    ... AskMayoExpert. Conjunctivitis. Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2014. Jan. 11, 2018 Original article: http://www.mayoclinic.org/symptoms/red-eye/basics/definition/SYM-20050748 . Mayo Clinic Footer Legal Conditions and ...

  4. Hand eczema

    Directory of Open Access Journals (Sweden)

    Uma Shankar Agarwal

    2014-01-01

    Full Text Available Hand eczema is often a chronic, multifactorial disease. It is usually related to occupational or routine household activities. Exact etiology of the disease is difficult to determine. It may become severe enough and disabling to many of patients in course of time. An estimated 2-10% of population is likely to develop hand eczema at some point of time during life. It appears to be the most common occupational skin disease, comprising 9-35% of all occupational diseases and up to 80% or more of all occupational contact dermatitis. So, it becomes important to find the exact etiology and classification of the disease and to use the appropriate preventive and treatment measures. Despite its importance in the dermatological practice, very few Indian studies have been done till date to investigate the epidemiological trends, etiology, and treatment options for hand eczema. In this review, we tried to find the etiology, epidemiology, and available treatment modalities for chronic hand eczema patients.

  5. Hand Washing

    Science.gov (United States)

    ... that mystery object in the park or your cat rub against you after using the litter pan. Fido and Fluffy are dirtier than you might think. Even if you're a good hand-washer, your friends may be harboring some ...

  6. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué Es el Ojo Seco? ...

  7. Do the eyes scan dream images during rapid eye movement sleep? Evidence from the rapid eye movement sleep behaviour disorder model.

    Science.gov (United States)

    Leclair-Visonneau, Laurène; Oudiette, Delphine; Gaymard, Bertrand; Leu-Semenescu, Smaranda; Arnulf, Isabelle

    2010-06-01

    Rapid eye movements and complex visual dreams are salient features of human rapid eye movement sleep. However, it remains to be elucidated whether the eyes scan dream images, despite studies that have retrospectively compared the direction of rapid eye movements to the dream recall recorded after having awakened the sleeper. We used the model of rapid eye movement sleep behaviour disorder (when patients enact their dreams by persistence of muscle tone) to determine directly whether the eyes move in the same directions as the head and limbs. In 56 patients with rapid eye movement sleep behaviour disorder and 17 healthy matched controls, the eye movements were monitored by electrooculography in four (right, left, up and down) directions, calibrated with a target and synchronized with video and sleep monitoring. The rapid eye movement sleep behaviour disorder-associated behaviours occurred 2.1 times more frequently during rapid eye movement sleep with than without rapid eye movements, and more often during or after rapid eye movements than before. Rapid eye movement density, index and complexity were similar in patients with rapid eye movement sleep behaviour disorder and controls. When rapid eye movements accompanied goal-oriented motor behaviour during rapid eye movement sleep behaviour disorder (e.g. grabbing a fictive object, hand greetings, climbing a ladder), which happened in 19 sequences, 82% were directed towards the action of the patient (same plane and direction). When restricted to the determinant rapid eye movements, the concordance increased to 90%. Rapid eye movements were absent in 38-42% of behaviours. This directional coherence between limbs, head and eye movements during rapid eye movement sleep behaviour disorder suggests that, when present, rapid eye movements imitate the scanning of the dream scene. Since the rapid eye movements are similar in subjects with and without rapid eye movement sleep behaviour disorder, this concordance can be extended

  8. Concurrent directional adaptation of reactive saccades and hand movements to target displacements of different size.

    Science.gov (United States)

    Borisova, Steliana; Bock, Otmar; Grigorova, Valentina

    2014-01-01

    When eye and hand movements are concurrently aimed at double-step targets that call for equal and opposite changes of response direction (-10° for the eyes, +10° for the hand), adaptive recalibration of both motor systems is strongly attenuated; instead, hand but not eye movements are changed by corrective strategies (V. Grigorova et al., 2013a). The authors introduce a complementary paradigm, where double-step targets call for a -10° change of eye and a -30° change for hand movements. If compared to control subjects adapting only the eyes or only the hand, adaptive improvements were comparable for the eyes but were twice as large for the hand; in contrast, eye and hand aftereffects were comparable to those in control subjects. The authors concluded that concurrent exposure of eyes and hand to steps of the same direction but different size facilitated hand strategies, but didn't affect recalibration. This finding together with previous one (V. Grigorova et al., 2013a), suggests that concurrent adaptation of eyes and hand reveals different mechanisms of recalibration for step sign and step size, which are shared by reactive saccades and hand movements. However, hand mostly benefits from strategies provoked by the difference in target step sign and size.

  9. Hands Off!

    DEFF Research Database (Denmark)

    Foss, Kirsten; Foss, Nicolai Juul

    a crucial issue when organizations want to sustain the advantages that may flow from delegation: Such advantages are dependent on motivated employees, and managerial overruling or reneging is harmful to motivation. However, little work has been done on how organizations can make delegation credible. We...... argue that key elements of organizations (i.e., organizational structure, coordination mechanisms, reward structures, and interdependencies between activities) and how these fit influence the credibility of delegation. Fit configurations of organizational elements reduce the probability of managerial...... intervention that may harm employee motivation. This introduces a neglected incentive dimension to the organizational design literature. Moreover, it is argued that harmful intervention may be reduced by increasing managers' costs of intervening. Refutable propositions are derived....

  10. Eye trauma

    African Journals Online (AJOL)

    2011-02-02

    Feb 2, 2011 ... Industrial workers should be protected by safety glasses but injuries occur nonetheless. Eye trauma is frequent in homes, farms and backyards where safety glasses are not available. Angle-grinders, metal beating, hammering, fence mending, herding animals, forestry, fire fighting and cutting sugar cane ...

  11. Your Eyes

    Science.gov (United States)

    ... OK if you ask to see their liver! Big as a Ping Pong Ball The eye is about as big as a ping-pong ball and sits in ... of sight! Reviewed by: Jonathan H. Salvin, MD Date reviewed: February 2015 More on this topic for: ...

  12. Eye trauma

    African Journals Online (AJOL)

    2011-02-02

    Feb 2, 2011 ... Stain cornea with fluorescein. It is advisable to examine the eye as soon as possible since a delay will invariably lead to lid swelling, making the examination far more difficult. This can be overcome using cotton tips to retract the eyelids, or lid retractors can be made from bent paper clips (Illustration 1).

  13. Height estimations based on eye measurements throughout a gait cycle

    DEFF Research Database (Denmark)

    Yang, Sylvia X M; Larsen, Peter K; Alkjær, Tine

    2014-01-01

    (EH) measurement, on the other hand, is less prone to concealment. The purpose of the present study was to investigate: (1) how the eye height varies during the gait cycle, and (2) how the eye height changes with head position. The eyes were plotted manually in APAS for 16 test subjects during...

  14. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball

    Overview From a technical perspective, CMS has been in “beam operation” state since 6th November. The detector is fully closed with all components operational and the magnetic field is normally at the nominal 3.8T. The UXC cavern is normally closed with the radiation veto set. Access to UXC is now only possible during downtimes of LHC. Such accesses must be carefully planned, documented and carried out in agreement with CMS Technical Coordination, Experimental Area Management, LHC programme coordination and the CCC. Material flow in and out of UXC is now strictly controlled. Access to USC remains possible at any time, although, for safety reasons, it is necessary to register with the shift crew in the control room before going down.It is obligatory for all material leaving UXC to pass through the underground buffer zone for RP scanning, database entry and appropriate labeling for traceability. Technical coordination (notably Stephane Bally and Christoph Schaefer), the shift crew and run ...

  15. Eye movement monitoring of memory.

    Science.gov (United States)

    Ryan, Jennifer D; Riggs, Lily; McQuiggan, Douglas A; McQuiggan, Doug

    2010-08-15

    Explicit (often verbal) reports are typically used to investigate memory (e.g. "Tell me what you remember about the person you saw at the bank yesterday."), however such reports can often be unreliable or sensitive to response bias, and may be unobtainable in some participant populations. Furthermore, explicit reports only reveal when information has reached consciousness and cannot comment on when memories were accessed during processing, regardless of whether the information is subsequently accessed in a conscious manner. Eye movement monitoring (eye tracking) provides a tool by which memory can be probed without asking participants to comment on the contents of their memories, and access of such memories can be revealed on-line. Video-based eye trackers (either head-mounted or remote) use a system of cameras and infrared markers to examine the pupil and corneal reflection in each eye as the participant views a display monitor. For head-mounted eye trackers, infrared markers are also used to determine head position to allow for head movement and more precise localization of eye position. Here, we demonstrate the use of a head-mounted eye tracking system to investigate memory performance in neurologically-intact and neurologically-impaired adults. Eye movement monitoring procedures begin with the placement of the eye tracker on the participant, and setup of the head and eye cameras. Calibration and validation procedures are conducted to ensure accuracy of eye position recording. Real-time recordings of X,Y-coordinate positions on the display monitor are then converted and used to describe periods of time in which the eye is static (i.e. fixations) versus in motion (i.e., saccades). Fixations and saccades are time-locked with respect to the onset/offset of a visual display or another external event (e.g. button press). Experimental manipulations are constructed to examine how and when patterns of fixations and saccades are altered through different types of prior

  16. Retrospectives: Ethics and the Invisible Hand

    OpenAIRE

    Jerry Evensky

    1993-01-01

    As modern economists, we use Adam Smith's "invisible hand" metaphor confident that we all know what it means in our discourse: it reflects our admiration for the elegant and smooth functioning of the market system as a coordinator of autonomous individual choices in an interdependent world. But in Adam Smith's moral philosophy, the invisible hand has a much broader responsibility: if individuals are to enjoy the fruits of a classical liberal society, the invisible hand must not only coordinat...

  17. Conjunctivitis (Pink Eye)

    Science.gov (United States)

    ... can put on your web pages. Conjunctivitis (Pink Eye) One-Page Overview Pink, itchy eyes? Conjunctivitis – or ... yourself from getting and spreading pink eye . Pink Eye: What To Do Discusses causes and treatment, when ...

  18. About the Eye

    Medline Plus

    Full Text Available ... NEI for Kids > About the Eye All About Vision About the Eye Ask a Scientist Video Series ... Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun ...

  19. Eye Disease Simulations

    Science.gov (United States)

    ... USAJobs Home > Eye Health Information > Eye Disease Simulations Eye Disease Simulations Age-Related Macular Degeneration Cataract Diabetic ... information page Back to top Diabetic Retinopathy Diabetic Eye Disease information page Back to top Glaucoma Glaucoma ...

  20. About the Eye

    Medline Plus

    Full Text Available ... USAJobs Home > NEI for Kids > About the Eye All About Vision About the Eye Ask a Scientist Video ... Vision Tips Protective Eyewear Sports and Your Eyes Fun Stuff Cool Eye Tricks Links to More Information ...

  1. About the Eye

    Medline Plus

    Full Text Available ... USAJobs Home > NEI for Kids > About the Eye All About Vision About the Eye Ask a Scientist ... Links to More Information Optical Illusions Printables About the Eye Your eyes are made up of many ...

  2. Eye muscle repair - discharge

    Science.gov (United States)

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  3. Diabetic Eye Disease

    Science.gov (United States)

    ... Disease, & Other Dental Problems Diabetes & Sexual & Urologic Problems Diabetic Eye Disease What is diabetic eye disease? Diabetic eye disease is a group ... eye diseases that can threaten your sight are Diabetic retinopathy The retina is the inner lining at ...

  4. About the Eye

    Medline Plus

    Full Text Available ... eye behind the iris that helps to focus light on the retina. It allows the eye to ... of the eye. It regulates the amount of light entering the eye through the pupil. Pupil (PYOO- ...

  5. Why Do Eyes Water?

    Science.gov (United States)

    ... for Educators Search English Español Why Do Eyes Water? KidsHealth / For Kids / Why Do Eyes Water? What's ... coming out of your nose. Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  6. Eye Movement Disorders

    Science.gov (United States)

    ... t work properly. There are many kinds of eye movement disorders. Two common ones are Strabismus - a disorder ... of the eyes, sometimes called "dancing eyes" Some eye movement disorders are present at birth. Others develop over ...

  7. Distributed Coordination of Household Electricity Consumption

    DEFF Research Database (Denmark)

    Juelsgaard, Morten; Teixeira, Andre; Johansson, Mikael

    2014-01-01

    This work presents a distributed framework for coordination of flexible electricity consumption for a number of households in the distribution grid. We conduct coordination with the purpose of minimizing a trade-off between individual concerns about discomfort and electricity cost, on the one hand...

  8. Eye Contricks

    Directory of Open Access Journals (Sweden)

    Nicholas J Wade

    2011-06-01

    Full Text Available Pictorial images are icons as well as eye-cons: they provide distillations of objects or ideas into simpler shapes. They create the impression of representing that which cannot be presented. Even at the level of the photograph, the links between icon and object are tenuous. The dimensions of depth and motion are missing from icons, and these alone introduce all manner of potential ambiguities. The history of art can be considered as exploring the missing link between icon and object. Eye-cons can also be illusions—tricks of vision so that what is seen does not necessarily correspond to what is physically presented. Pictorial images can be spatialised or stylised; spatialised images generally share some of the projective characteristics of the object represented. Written words are also icons, but they do not resemble the objects they represent—they are stylised or conventional. Icons as stylised words and spatialised images were set in delightful opposition by René Magritte in a series of pipe paintings, and this theme is here alluded to. Most of visual science is now concerned with icons—two-dimensional displays on computer monitors. Is vision now the science of eye-cons?

  9. Preventing Eye Injuries

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating Eye ... Five Steps to Safer Champagne Celebrations Preventing Eye Injuries Leer en Español: Lesiones de los Ojos Reviewed ...

  10. Hand Grasping Synergies As Biometrics

    Directory of Open Access Journals (Sweden)

    Ramana Vinjamuri

    2017-05-01

    Full Text Available Recently, the need for more secure identity verification systems has driven researchers to explore other sources of biometrics. This includes iris patterns, palm print, hand geometry, facial recognition, and movement patterns (hand motion, gait, and eye movements. Identity verification systems may benefit from the complexity of human movement that integrates multiple levels of control (neural, muscular, and kinematic. Using principal component analysis, we extracted spatiotemporal hand synergies (movement synergies from an object grasping dataset to explore their use as a potential biometric. These movement synergies are in the form of joint angular velocity profiles of 10 joints. We explored the effect of joint type, digit, number of objects, and grasp type. In its best configuration, movement synergies achieved an equal error rate of 8.19%. While movement synergies can be integrated into an identity verification system with motion capture ability, we also explored a camera-ready version of hand synergies—postural synergies. In this proof of concept system, postural synergies performed well, but only when specific postures were chosen. Based on these results, hand synergies show promise as a potential biometric that can be combined with other hand-based biometrics for improved security.

  11. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball

    2010-01-01

    Operational Experience At the end of the first full-year running period of LHC, CMS is established as a reliable, robust and mature experiment. In particular common systems and infrastructure faults accounted for <0.6 % CMS downtime during LHC pp physics. Technical operation throughout the entire year was rather smooth, the main faults requiring UXC access being sub-detector power systems and rack-cooling turbines. All such problems were corrected during scheduled technical stops, in the shadow of tunnel access needed by the LHC, or in negotiated accesses or access extensions. Nevertheless, the number of necessary accesses to the UXC averaged more than one per week and the technical stops were inevitably packed with work packages, typically 30 being executed within a few days, placing a high load on the coordination and area management teams. It is an appropriate moment for CMS Technical Coordination to thank all those in many CERN departments and in the Collaboration, who were involved in CMS techni...

  12. Waiting for a hand: saccadic reaction time increases in proportion to hand reaction time when reaching under a visuomotor reversal

    Directory of Open Access Journals (Sweden)

    Irene eArmstrong

    2013-07-01

    Full Text Available Although eye movement onset typically precedes hand movement onset when reaching to targets presented in peripheral vision, arm motor commands appear to be issued at around the same time, and possibly in advance, of eye motor commands. A fundamental question, therefore, is whether eye movement initiation is linked or yoked to hand movement. We addressed this issue by having participants reach to targets after adapting to a visuomotor reversal (or 180° rotation between the position of the unseen hand and the position of a cursor controlled by the hand. We asked whether this reversal, which we expected to increase hand reaction time (HRT, would also increase saccadic reaction time (SRT. As predicted, when moving the cursor to targets under the reversal, HRT increased in all participants. SRT also increased in all but one participant, even though the task for the eyes – shifting gaze to the target – was unaltered by the reversal of hand position feedback. Moreover, the effects of the reversal on SRT and HRT were positively correlated across participants; those who exhibited the greatest increases in HRT also showed the greatest increases in SRT. These results indicate that the mechanisms underlying the initiation of eye and hand movements are linked. In particular, the results suggest that the initiation of an eye movement to a manual target depends, at least in part, on the specification of hand movement.

  13. The visual development of hand-centered receptive fields in a neural network model of the primate visual system trained with experimentally recorded human gaze changes.

    Science.gov (United States)

    Galeazzi, Juan M; Navajas, Joaquín; Mender, Bedeho M W; Quian Quiroga, Rodrigo; Minini, Loredana; Stringer, Simon M

    2016-01-01

    Neurons have been found in the primate brain that respond to objects in specific locations in hand-centered coordinates. A key theoretical challenge is to explain how such hand-centered neuronal responses may develop through visual experience. In this paper we show how hand-centered visual receptive fields can develop using an artificial neural network model, VisNet, of the primate visual system when driven by gaze changes recorded from human test subjects as they completed a jigsaw. A camera mounted on the head captured images of the hand and jigsaw, while eye movements were recorded using an eye-tracking device. This combination of data allowed us to reconstruct the retinal images seen as humans undertook the jigsaw task. These retinal images were then fed into the neural network model during self-organization of its synaptic connectivity using a biologically plausible trace learning rule. A trace learning mechanism encourages neurons in the model to learn to respond to input images that tend to occur in close temporal proximity. In the data recorded from human subjects, we found that the participant's gaze often shifted through a sequence of locations around a fixed spatial configuration of the hand and one of the jigsaw pieces. In this case, trace learning should bind these retinal images together onto the same subset of output neurons. The simulation results consequently confirmed that some cells learned to respond selectively to the hand and a jigsaw piece in a fixed spatial configuration across different retinal views.

  14. Tropical diabetic hand syndrome: a case report.

    Science.gov (United States)

    Yeika, Eugene Vernyuy; Tchoumi Tantchou, Jacques Cabral; Foryoung, Joyce Bei; Tolefac, Paul Nkemtendong; Efie, Derrick Tembi; Choukem, Siméon Pierre

    2017-02-13

    Tropical diabetic hand syndrome describes a complex hand sepsis affecting patients with diabetes across the tropics and often results from a trivial hand trauma. The clinical presentation of this syndrome is variable and ranges from localised swelling and cellulitis, with or without ulceration of the hand to progressive fulminant hand sepsis, and gangrene affecting the entire limb which may be fatal. Tropical diabetic hand syndrome could lead to permanent disability and death as a result of delay in presentation, late diagnosis and late medical and surgical intervention. This indexed case acts as an eye opener for physicians to the existence of this hand sepsis. We report the case of a 57 year-old black African female diabetic who was referred to our centre for the management of a suppurating ulcer and swelling of the left hand of two weeks duration. On examination and work-up, the patient was found to have Lawal Group III left diabetic hand syndrome and was managed with parenteral antibiotics, radical debridement and the hand was eventually amputated. She died 7 days following amputation from overwhelming sepsis. Though tropical diabetic hand syndrome is a relatively rare complication of diabetes, it can be fatal as in this case report. Early diagnosis and proper management would yield better outcome. Initial management should include aggressive intravenous broad-spectrum antibiotics with anaerobic coverage. Classification of tropical diabetic hand syndrome will assist physicians and surgeons in decision making, proper management and easy communication.

  15. Coordination Processes in International Organisations

    DEFF Research Database (Denmark)

    Nedergaard, Peter

    2008-01-01

    The EU is not a member of the International Labour Organisation (ILO), but relatively elaborate EU coordination takes place anyway. This paper addresses two research questions: 1) How is it possible to evaluate the coordination of the EU in its specific observable configuration in the ILO?, and 2......-à-vis their principals, the Member States. The Commission is the leading agent in the phase leading up to the Conference; the Presidency then takes over. On the one hand, due to the Treaty obligations and their interpretations by the Court of Justice, both the Presidency and the Commission are kept within tight limits...

  16. Control design and implementation of a novel master-slave surgery robot system, MicroHand A.

    Science.gov (United States)

    Sang, Hongqiang; Wang, Shuxin; Li, Jianmin; He, Chao; Zhang, Lin'an; Wang, Xiaofei

    2011-09-01

    Compared with conventional minimally invasive surgery and open surgery, robotic-assisted minimally invasive surgery can overcome or eliminate drawbacks caused by operator restrictions, motion limitation by the trocar and the image system, such as fatigue, trembling, low precision, constrained degree-of-freedom, poor hand-eye coordination and restricted surgical vision. In this paper, a novel partly tendon-driven master-slave robot system is proposed to assist minimally invasive surgery and a master-slave control architecture is developed for abdominal surgical operations. A novel master-slave surgery robot system named MicroHand A has been developed. A kinematic analysis of master and slave manipulators was conducted, based on screw theory and vector loop equation. The relationships of the tendon-driven multi-DOF surgical instrument among Cartesian space, actuator space and joint space were derived for control purposes. The control system architecture of the MicroHand A was designed with intuitive motion control and motion scaling control. Llewellyn's absolute stability criterion and the transparency of the one-DOF master-slave system are also analysed. Intuitive motion control under dissimilar kinematics in master-slave manipulations and motion scaling control were accomplished to solve absonant hand-eye coordination, kinematic dissimilarity and workspace mismatch of master-slave manipulator problems. A series of tests and animal experiments were carried out to evaluate system performance. The experimental results demonstrate that the system could accomplish intuitive motion control and motion scaling control, and that the control system is stable and reliable. The experiments performed on the MicroHand A robotic system yielded expected control results. The system satisfies the requirements of minimally invasive surgery. Intuitive motion control and motion scaling control under different kinematics for the master and slave have been implemented. Copyright © 2011

  17. RUN COORDINATION

    CERN Multimedia

    C. Delaere

    2013-01-01

    Since the LHC ceased operations in February, a lot has been going on at Point 5, and Run Coordination continues to monitor closely the advance of maintenance and upgrade activities. In the last months, the Pixel detector was extracted and is now stored in the pixel lab in SX5; the beam pipe has been removed and ME1/1 removal has started. We regained access to the vactank and some work on the RBX of HB has started. Since mid-June, electricity and cooling are back in S1 and S2, allowing us to turn equipment back on, at least during the day. 24/7 shifts are not foreseen in the next weeks, and safety tours are mandatory to keep equipment on overnight, but re-commissioning activities are slowly being resumed. Given the (slight) delays accumulated in LS1, it was decided to merge the two global runs initially foreseen into a single exercise during the week of 4 November 2013. The aim of the global run is to check that we can run (parts of) CMS after several months switched off, with the new VME PCs installed, th...

  18. RUN COORDINATION

    CERN Multimedia

    Christophe Delaere

    2013-01-01

    The focus of Run Coordination during LS1 is to monitor closely the advance of maintenance and upgrade activities, to smooth interactions between subsystems and to ensure that all are ready in time to resume operations in 2015 with a fully calibrated and understood detector. After electricity and cooling were restored to all equipment, at about the time of the last CMS week, recommissioning activities were resumed for all subsystems. On 7 October, DCS shifts began 24/7 to allow subsystems to remain on to facilitate operations. That culminated with the Global Run in November (GriN), which   took place as scheduled during the week of 4 November. The GriN has been the first centrally managed operation since the beginning of LS1, and involved all subdetectors but the Pixel Tracker presently in a lab upstairs. All nights were therefore dedicated to long stable runs with as many subdetectors as possible. Among the many achievements in that week, three items may be highlighted. First, the Strip...

  19. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué ... Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  20. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Dry Eye ... Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué Es el Ojo Seco? Written By: Kierstan ...

  1. About the Eye

    Medline Plus

    Full Text Available ... Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun Stuff Cool Eye Tricks Links to More Information Optical Illusions Printables About the Eye Your eyes ...

  2. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Eye Health Find an Ophthalmologist Academy Store Eye Health A- ... Get ophthalmologist-reviewed tips and information about eye health and preserving your vision. Privacy ... Choosing Wisely When It Comes to Eye Care, Part 5 Mar 19, 2013 Eye Makeup Safety ...

  3. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Health Find an Ophthalmologist Academy Store Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News Ask ... Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? ...

  4. Pathways to clean hands: highlights of successful hand hygiene implementation strategies in Europe.

    Science.gov (United States)

    Magiorakos, A P; Leens, E; Drouvot, V; May-Michelangeli, L; Reichardt, C; Gastmeier, P; Wilson, K; Tannahill, M; McFarlane, E; Simon, A

    2010-05-06

    Hand hygiene is the most effective way to stop the spread of microorganisms and to prevent healthcare-associated infections (HAI). The World Health Organization launched the First Global Patient Safety Challenge - Clean Care is Safer Care - in 2005 with the goal to prevent HAI globally. This year, on 5 May, the WHO s initiative SAVE LIVES: Clean Your Hands, which focuses on increasing awareness of and improving compliance with hand hygiene practices, celebrated its second global day. In this article, four Member States of the European Union describe strategies that were implemented as part of their national hand hygiene campaigns and were found to be noteworthy. The strategies were: governmental support, the use of indicators for hand hygiene benchmarking, developing national surveillance systems for auditing alcohol-based hand rub consumption, ensuring seamless coordination of processes between health regions in countries with regionalised healthcare systems, implementing the WHO's My Five Moments for Hand Hygiene, and auditing of hand hygiene compliance.

  5. About the Eye

    Medline Plus

    Full Text Available ... Cool Eye Tricks Links to More Information Optical Illusions Printables About the Eye Your eyes are made ... of the macula, where your vision is sharpest. Optic nerve (OP-tic nurv) is the bundle of ...

  6. About the Eye

    Medline Plus

    Full Text Available ... and other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and ... National Eye Health Education Program (NEHEP) Diabetic Eye Disease Education Program Glaucoma Education Program Low Vision Education ...

  7. About the Eye

    Medline Plus

    Full Text Available ... Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision ... to More Information Optical Illusions Printables About the Eye Your eyes are made up of many different ...

  8. Dilating Eye Drops

    Science.gov (United States)

    ... Frequently Asked Questions Español Condiciones Chinese Conditions Dilating Eye Drops En Español Read in Chinese What are dilating eye drops? Dilating eye drops contain medication to enlarge ( ...

  9. About the Eye

    Science.gov (United States)

    ... Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision ... to More Information Optical Illusions Printables About the Eye Your eyes are made up of many different ...

  10. Eyes, Bulging (Proptosis)

    Science.gov (United States)

    ... Therapy for Kids With Rare Eye Disease (Video) Ocular Implant (Video) Glaucoma Additional Content Medical News Eyes, ... has other eye symptoms, such as dryness, increased tear formation, double vision, loss of vision, irritation, or ...

  11. What Is Dry Eye?

    Medline Plus

    Full Text Available ... vision? May 27, 2017 Is stopping Restasis dangerous? Mar 06, 2017 Why are my eyes bloodshot when ... When It Comes to Eye Care, Part 5 Mar 19, 2013 Eye Makeup Safety Tips Sep 25, ...

  12. LASIK eye surgery

    Science.gov (United States)

    ... to correct a very nearsighted eye may prevent amblyopia (lazy eye). Your eyes must be healthy and ... any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should ...

  13. About the Eye

    Medline Plus

    Full Text Available ... and other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of ... National Eye Health Education Program (NEHEP) Diabetic Eye Disease Education Program Glaucoma Education Program Low Vision Education ...

  14. Eye muscle repair - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100062.htm Eye muscle repair - series—Normal anatomy To use the sharing ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ...

  15. EyeGENE

    Data.gov (United States)

    U.S. Department of Health & Human Services — The eyeGENE® Biorepository and corresponding Database contain family history and clinical eye exam data from subjects enrolled in eyeGENE® Program coupled to...

  16. What Is Dry Eye?

    Medline Plus

    Full Text Available ... also when your eyes do not make the right type of tears or tear film. How do ... information about eye health and preserving your vision. Privacy Policy Related New Dry Eye Treatment is a ...

  17. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Member Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member ... Center Redmond Ethics Center Global Ophthalmology Guide Eye Health Find an Ophthalmologist Academy Store Eye Health A- ...

  18. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Get ophthalmologist-reviewed tips and information about eye health and preserving your vision. Privacy ... Choosing Wisely When It Comes to Eye Care, Part 5 Mar 19, 2013 Eye Makeup Safety ...

  19. Binocular coordination in response to stereoscopic stimuli

    Science.gov (United States)

    Liversedge, Simon P.; Holliman, Nicolas S.; Blythe, Hazel I.

    2009-02-01

    Humans actively explore their visual environment by moving their eyes. Precise coordination of the eyes during visual scanning underlies the experience of a unified perceptual representation and is important for the perception of depth. We report data from three psychological experiments investigating human binocular coordination during visual processing of stereoscopic stimuli.In the first experiment participants were required to read sentences that contained a stereoscopically presented target word. Half of the word was presented exclusively to one eye and half exclusively to the other eye. Eye movements were recorded and showed that saccadic targeting was uninfluenced by the stereoscopic presentation, strongly suggesting that complementary retinal stimuli are perceived as a single, unified input prior to saccade initiation. In a second eye movement experiment we presented words stereoscopically to measure Panum's Fusional Area for linguistic stimuli. In the final experiment we compared binocular coordination during saccades between simple dot stimuli under 2D, stereoscopic 3D and real 3D viewing conditions. Results showed that depth appropriate vergence movements were made during saccades and fixations to real 3D stimuli, but only during fixations on stereoscopic 3D stimuli. 2D stimuli did not induce depth vergence movements. Together, these experiments indicate that stereoscopic visual stimuli are fused when they fall within Panum's Fusional Area, and that saccade metrics are computed on the basis of a unified percept. Also, there is sensitivity to non-foveal retinal disparity in real 3D stimuli, but not in stereoscopic 3D stimuli, and the system responsible for binocular coordination responds to this during saccades as well as fixations.

  20. Laser photocoagulation - eye

    Science.gov (United States)

    Laser coagulation; Laser eye surgery; Photocoagulation; Laser photocoagulation - diabetic eye disease; Laser photocoagulation - diabetic retinopathy; Focal photocoagulation; Scatter (or pan retinal) photocoagulation; Proliferative ...

  1. Head and eye movements in unrestrained pigeons (Columba livia)

    OpenAIRE

    Wohlschläger, Andreas; Jäger, Ralf; Delius, Juan

    1993-01-01

    Head and eye movements were simultaneously recorded during locomotory and pecking behavior of 4 pigeons, which were trained to traverse a conditioning chamber, with a pecking key and a food dispenser at each end. Each trial involved key pecking, walking, and feeding. Head movements were registered with a skull-mounted miniature accelerometer, and eye movements were recorded with implanted electrooculogram (EOG) electrodes. An almost perfect temporal coordination between head and eye movements...

  2. Hand gesture guided robot-assisted surgery based on a direct augmented reality interface.

    Science.gov (United States)

    Wen, Rong; Tay, Wei-Liang; Nguyen, Binh P; Chng, Chin-Boon; Chui, Chee-Kong

    2014-09-01

    Radiofrequency (RF) ablation is a good alternative to hepatic resection for treatment of liver tumors. However, accurate needle insertion requires precise hand-eye coordination and is also affected by the difficulty of RF needle navigation. This paper proposes a cooperative surgical robot system, guided by hand gestures and supported by an augmented reality (AR)-based surgical field, for robot-assisted percutaneous treatment. It establishes a robot-assisted natural AR guidance mechanism that incorporates the advantages of the following three aspects: AR visual guidance information, surgeon's experiences and accuracy of robotic surgery. A projector-based AR environment is directly overlaid on a patient to display preoperative and intraoperative information, while a mobile surgical robot system implements specified RF needle insertion plans. Natural hand gestures are used as an intuitive and robust method to interact with both the AR system and surgical robot. The proposed system was evaluated on a mannequin model. Experimental results demonstrated that hand gesture guidance was able to effectively guide the surgical robot, and the robot-assisted implementation was found to improve the accuracy of needle insertion. This human-robot cooperative mechanism is a promising approach for precise transcutaneous ablation therapy. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  3. Improving eye care in Rwanda.

    Science.gov (United States)

    Binagwaho, Agnes; Scott, Kirstin; Rosewall, Thomas; Mackenzie, Graeme; Rehnborg, Gweneth; Hannema, Sjoerd; Presente, Max; Noe, Piet; Mathenge, Wanjiku; Nkurikiye, John; Habiyaremye, Francois; Dushime, Theophile

    2015-06-01

    Visual impairment affects nearly 285 million people worldwide. Although there has been much progress in combating the burden of visual impairment through initiatives such as VISION 2020, barriers to progress, especially in African countries, remain high. The Rwandan Ministry of Health has formed partnerships with several nongovernmental organizations and has worked to integrate their efforts to prevent and treat visual impairment, including presbyopia. Rwanda, an eastern African country of approximately 11 million people. The Rwandan Ministry of Health developed a single national plan that allows key partners in vision care to coordinate more effectively in measuring eye disease, developing eye care infrastructure, building capacity, controlling disease, and delivering and evaluating services. Collaboration between stakeholders under a single national plan has ensured that resources and efforts are complementary, optimizing the ability to provide eye care. Improved access to primary eye care and insurance coverage has increased demand for services at secondary and tertiary levels. A comprehensive strategy that includes prevention as well as a supply chain for glasses and lenses is needed.

  4. Clean Hands Count

    Medline Plus

    Full Text Available ... hand hygiene and empower patients to play a role in their care by asking or reminding healthcare providers to clean their hands. See: ... Hand Washing For Nurses - Duration: 2:57. Kevin Gorin 213,219 views ...

  5. Hand and Wrist Tumors

    Science.gov (United States)

    ... Therapist? Media Find a Hand Surgeon Home Anatomy Hand Tumors and Wrist Tumors Email to a friend * ... are seen commonly. CAUSES Common Types of Wrist Hand Tumors Ganglion Cysts (Figure 1): This is the ...

  6. Hand splint - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100142.htm Hand splint - series—Indications To use the sharing features ... out of 4 Overview To begin making a hand dressing, place the injured hand around a cloth ...

  7. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... and public health professionals. More > Hand Hygiene Saves Lives (5:10) Recommend on Facebook Tweet Share Compartir Hand Hygiene Saves Lives Hand Hygiene Saves Lives Transcript [28 KB, 2 pages] High resolution [22. ...

  8. Hand Hygiene Saves Lives

    Science.gov (United States)

    ... and public health professionals. More > Hand Hygiene Saves Lives (5:10) Recommend on Facebook Tweet Share Compartir Hand Hygiene Saves Lives Hand Hygiene Saves Lives Transcript [28 KB, 2 pages] High resolution [22. ...

  9. In a demanding task, three-handed manipulation is preferred to two-handed manipulation

    Science.gov (United States)

    Abdi, Elahe; Burdet, Etienne; Bouri, Mohamed; Himidan, Sharifa; Bleuler, Hannes

    2016-02-01

    Equipped with a third hand under their direct control, surgeons may be able to perform certain surgical interventions alone; this would reduce the need for a human assistant and related coordination difficulties. However, does human performance improve with three hands compared to two hands? To evaluate this possibility, we carried out a behavioural study on the performance of naive adults catching objects with three virtual hands controlled by their two hands and right foot. The subjects could successfully control the virtual hands in a few trials. With this control strategy, the workspace of the hands was inversely correlated with the task velocity. The comparison of performance between the three and two hands control revealed no significant difference of success in catching falling objects and in average effort during the tasks. Subjects preferred the three handed control strategy, found it easier, with less physical and mental burden. Although the coordination of the foot with the natural hands increased trial after trial, about two minutes of practice was not sufficient to develop a sense of ownership towards the third arm.

  10. About the Eye

    Medline Plus

    Full Text Available ... the eye behind the iris that helps to focus light on the retina. It allows the eye to focus on both far and near objects. Iris is ... front of your eye. It helps your eye focus light so things look sharp and clear. Sclera ( ...

  11. About the Eye

    Medline Plus

    Full Text Available ... All About Vision About the Eye Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun Stuff Cool Eye Tricks ...

  12. Eye Injuries in Sports

    Science.gov (United States)

    ... very high risk. This includes boxing, wrestling, and martial arts.There are several types of common eye injuries in sports.Blunt trauma injuries. These occur when something or someone hits you in or around your eye. A black eye is bruising of your eye, eyelid, or ...

  13. Recognizing and Treating Eye Injuries

    Science.gov (United States)

    ... Patient Stories Español Eye Health / Tips & Prevention Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating Eye ... to Safer Champagne Celebrations Recognizing and Treating Eye Injuries Leer en Español: Reconociendo las Lesiones de los ...

  14. Neural constraints on eye motion in human eye-head saccades.

    Science.gov (United States)

    Misslisch, H; Tweed, D; Vilis, T

    1998-02-01

    slit glasses, their EOMRs shrank mostly in the direction perpendicular to the slit, showing that altered vision can change the shape as well as the size of the EOMR. A recent, three-dimensional model of eye-head coordination can explain all these findings if we add to it a mechanism for adjusting the EOMR.

  15. Denmark: HAND in HAND Policy Questionnaire

    DEFF Research Database (Denmark)

    Laursen, Hilmar Dyrborg; Nielsen, Birgitte Lund

    2018-01-01

    Som del af det internationale EU finansierede projekt Hand in Hand, der fokuserer på de såkaldte SEI-kompetencer (Social, Emotional, Intercultural), er dansk policy i relation til elevernes sociale, emotionelle og interkulturelle læring kortlagt i denne rapport. Der refereres bl.a. til "elevernes...

  16. Pain ameliorating effect of eye movement desensitization.

    Science.gov (United States)

    Hekmat, H; Groth, S; Rogers, D

    1994-06-01

    This study explores the efficacy of eye movement desensitization and reprocessing (EMD/R) in the management of acute pain induced by hand exposures to ice water. Thirty participants were randomly assigned to one of the following interventions: (a) eye movement desensitization and reprocessing, (b) eye movement desensitization with music (EMD/M), and (c) control. The EMD/R participants focused on negative experiences associated with exposure to ice water, generated positive self-talk, and diverted their attention away from pain by focusing on a rapidly moving light on a monitor. The EMD with music group received eye movement desensitization coupled with preferred music. Repeated measures univariate and multivariate analysis of covariance was used to analyze the data. Results indicated that both procedures alleviated participants' pain to a similar degree and significantly more than the control, P < 0.05.

  17. Adamkus tries hand at mediating in eye of Ukrainian maelstrom

    Index Scriptorium Estoniae

    2004-01-01

    Leedu president Valdas Adamkus sõitis Leonid Kutshma kutsel Ukrainasse vahendamaks läbirääkimisi presidendikandidaatide - opositsiooniliider Viktor Jushtshenko ja peaminister Viktor Janukovitshi vahel

  18. A step toward robot teleoperation with eyes and hand

    OpenAIRE

    Despinoy, Fabien; Vitrani, Marie-Aude; Herman, Benoît; 4th International Workshop on Human-Friendly Robotics (HFR 2011)

    2012-01-01

    Despite the continuous improvement of master interfaces, distant robot teleoperation remains a challenging task. In many applications (e.g. spaceships, underwater or flying drones, robotic arms that operate in hazardous conditions in factories), the operator has only an indirect vision of the remote environment, provided by a video camera usually mounted on the robot end-effector itself, and displayed on a 2D monitor. Whereas any controller is capable of planning a path to follow a prescribed...

  19. Head and eye movement as pointing modalities for eyewear computers

    DEFF Research Database (Denmark)

    Jalaliniya, Shahram; Mardanbeigi, Diako; Pederson, Thomas

    2014-01-01

    While the new generation of eyewear computers have increased expectations of a wearable computer, providing input to these devices is still challenging. Hand-held devices, voice commands, and hand gestures have already been explored to provide input to the wearable devices. In this paper, we...... examined using head and eye movements to point on a graphical user interface of a wearable computer. The performance of users in head and eye pointing has been compared with mouse pointing as a baseline method. The result of our experiment showed that the eye pointing is significantly faster than head...

  20. Eyes Wide Open

    Directory of Open Access Journals (Sweden)

    Zoi Manesi

    2016-04-01

    Full Text Available Research from evolutionary psychology suggests that the mere presence of eye images can promote prosocial behavior. However, the “eye images effect” is a source of considerable debate, and findings across studies have yielded somewhat inconsistent support. We suggest that one critical factor may be whether the eyes really need to be watching to effectively enhance prosocial behavior. In three experiments, we investigated the impact of eye images on prosocial behavior, assessed in a laboratory setting. Participants were randomly assigned to view an image of watching eyes (eyes with direct gaze, an image of nonwatching eyes (i.e., eyes closed for Study 1 and averted eyes for Studies 2 and 3, or an image of flowers (control condition. Upon exposure to the stimuli, participants decided whether or not to help another participant by completing a dull cognitive task. Three independent studies produced somewhat mixed results. However, combined analysis of all three studies, with a total of 612 participants, showed that the watching component of the eyes is important for decision-making in this context. Images of watching eyes led to significantly greater inclination to offer help as compared to images of nonwatching eyes (i.e., eyes closed and averted eyes or images of flowers. These findings suggest that eyes gazing at an individual, rather than any proxy to social presence (e.g., just the eyes, serve as a reminder of reputation. Taken together, we conclude that it is “eyes that pay attention” that can lift the veil of anonymity and potentially facilitate prosocial behavior.

  1. Eye movements of vertebrates and their relation to eye form and function.

    Science.gov (United States)

    Land, Michael F

    2015-02-01

    The types of eye movements shown by all vertebrates originated in the earliest fishes. These consisted of compensatory movements, both vestibular and visual, to prevent image motion, and saccades to relocate gaze. All vertebrates fixate food items with their heads to enable ingestion, but from teleosts onwards some species also use eye movements to target particular objects, especially food. Eye movement use is related to the resolution distribution in the retina, with eyes that contain foveas, or areas of high ganglion cell density, being more likely to make targeting eye movements, not seen in animals with more uniform retinas. Birds, in particular, tend mainly to use head movements when shifting gaze. Many birds also make translatory head saccades (head bobbing) when walking. It is common for animals to use both eyes when locating food items ahead, but the use of binocular disparity for distance judgment is rare, and has only been demonstrated in toads, owls, cats and primates. Smooth tracking with eyes alone is probably confined to primates. The extent of synchrony and directional symmetry in the movements of the two eyes varies greatly, from complete independence in the sandlance and chameleon, to perfect coordination in primates.

  2. [Hand and endocrine diseases].

    Science.gov (United States)

    Wémeau, Jean-Louis; Ryndak, Amélie; Karrouz, Wassila; Balavoine, Anne-Sophie; Baudoux, Florence

    2013-12-01

    The whole of hormones likely influence state of hands, modifying colouring and trophicity of the skin and having influence on its muscular, tendineous, osseous, articular components. Thus state of the hands contributes to the recognition of the endocrine diseases: hot and moist hands of the Graves' disease, dry, cold and infiltrated hands in myxoedema, pale and fine hands of hypopituitarism, broad and thick hand of acromegaly, brachymetacarpia in the pseudohypoparathyroidism… Diabetes exposes particularly to tendineous and articular retractions, to whitlows and ungual mycosis. Copyright © 2013. Published by Elsevier Masson SAS.

  3. About the Eye

    Medline Plus

    Full Text Available ... First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun Stuff Cool Eye Tricks ... NEI Office of Science Communications, Public Liaison, and Education. Technical questions about this website can be addressed ...

  4. About the Eye

    Medline Plus

    Full Text Available ... you see. Check out the diagrams below to learn about each part of your eye and what ... the optic nerve to the brain. Watch now! Learn how the different parts of your eye work ...

  5. What Is Dry Eye?

    Medline Plus

    Full Text Available ... 12, 2017 Can lupus affect my vision? May 27, 2017 Is stopping Restasis dangerous? Mar 06, 2017 ... link between seasonal allergens and dry eye Apr 27, 2015 Choosing Wisely When It Comes to Eye ...

  6. Eye muscle repair

    Science.gov (United States)

    ... child may go home. You should have a follow-up visit with the eye surgeon 1 to 2 weeks after the surgery. To prevent infection, you will probably need to put drops or ointment in your child's eyes.

  7. National Eye Institute

    Science.gov (United States)

    ... testing new therapies. Learn more Learn about the Eye and Vision Our web pages for kids make ... illusions, and more. View the site Video: New Eye Imaging Tools The NEI Audacious Goals Initiative is ...

  8. About the Eye

    Medline Plus

    Full Text Available ... Education Programs National Eye Health Education Program (NEHEP) Diabetic Eye Disease Education Program Glaucoma Education Program Low ... iris adjusts the size of the pupil and controls the amount of light that can enter the ...

  9. What Is Dry Eye?

    Medline Plus

    Full Text Available ... vision? May 27, 2017 Is stopping Restasis dangerous? Mar 06, 2017 Why are my eyes bloodshot when ... When It Comes to Eye Care, Part 5 Mar 19, 2013 Follow The Academy Professionals: Education Guidelines ...

  10. Eye Drop Tips

    Science.gov (United States)

    ... Involved News About Us Donate In This Section Eye Drop Tips en Español email Send this article ... the reach of children. Steps For Putting In Eye Drops: Start by tilting your head backward while ...

  11. Lasik eye surgery - discharge

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000525.htm Lasik eye surgery - discharge To use the sharing features on this page, please enable JavaScript. Lasik eye surgery permanently changes the shape of the cornea ( ...

  12. About the Eye

    Medline Plus

    Full Text Available ... Links to More Information Optical Illusions Printables About the Eye Your eyes are made up of many ... make sense of the world around you. Did You Know? Vision depends on your brain as much ...

  13. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & More Academy Publications EyeNet Ophthalmology Ophthalmology Retina Information for: International Ophthalmologists Media Medical Students Patients and ...

  14. Eye Cosmetic Safety

    Science.gov (United States)

    ... eye (scratching your cornea, for example) with a mascara wand or other applicator. Even a slight scratch ... containers of eye cosmetics. Manufacturers usually recommend discarding mascara two to four months after purchase. Discard dried- ...

  15. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member Services ... 2015 Choosing Wisely When It Comes to Eye Care, Part 5 Mar 19, 2013 Follow The Academy ...

  16. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & More Academy Publications EyeNet Ophthalmology Ophthalmology Retina Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians ...

  17. About the Eye

    Medline Plus

    Full Text Available ... Clinical Studies Publications Catalog Photos and Images Spanish Language Information Grants and Funding Extramural Research Division of ... National Eye Health Education Program (NEHEP) Diabetic Eye Disease Education Program Glaucoma Education Program Low Vision Education ...

  18. Cultivating the Third Eye

    National Research Council Canada - National Science Library

    Holden, Constance

    2005-01-01

    Zoologist Om Prakash Jangir and his colleagues found that if the removed tadpoles' eyes and raised the animals in a medium enriched with vitamin A, a new eye developed within ten days over the site of the pineal gland...

  19. Eye Injuries at Home

    Science.gov (United States)

    ... Steps to Safer Champagne Celebrations Eye Injuries at Home Leer en Español: Lesiones de los Ojos en ... chore is being done. Preventing Eye Injuries at Home Wearing protective eyewear will prevent 90 percent of ...

  20. About the Eye

    Medline Plus

    Full Text Available ... System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy ... Your eyes are made up of many different parts that work together to help you see. Check out the ...

  1. Bags Under Eyes

    Science.gov (United States)

    ... can include: Mild swelling Saggy or loose skin Dark circles When to see a doctor You may not ... Rochester, Minn., July 22, 2014. Related Chemical peel Dark circles under eyes Bags under eyes Symptoms & causes Diagnosis & ...

  2. Eyes Wide Open

    OpenAIRE

    Zoi Manesi; Van Lange, Paul A. M.; Pollet, Thomas V.

    2016-01-01

    Research from evolutionary psychology suggests that the mere presence of eye images can promote prosocial behavior. However, the “eye images effect” is a source of considerable debate, and findings across studies have yielded somewhat inconsistent support. We suggest that one critical factor may be whether the eyes really need to be watching to effectively enhance prosocial behavior. In three experiments, we investigated the impact of eye images on prosocial behavior, assessed in a laboratory...

  3. Hand fracture - aftercare

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000552.htm Hand fracture - aftercare To use the sharing features on ... need to be repaired with surgery. Types of Hand Fractures Your fracture may be in one of ...

  4. Clean Hands Count

    Medline Plus

    Full Text Available ... Queue __count__/__total__ Find out why Close Clean Hands Count Centers for Disease Control and Prevention (CDC) ... intended to promote or encourage adherence to CDC hand hygiene recommendations. It is a component of the ...

  5. Hand and Finger Exercises

    Science.gov (United States)

    Hand and Finger Exercises  Place your palm flat on a table. Raise and lower your fingers one ... times for ____ seconds.  Pick up objects with your hand. Start out with larger objects. Repeat ____ times for ____ ...

  6. Clean Hands Count

    Medline Plus

    Full Text Available ... misperceptions about hand hygiene and empower patients to play a role in their care by asking or ... autoplay is enabled, a suggested video will automatically play next. Up next Wash your Hands - it just ...

  7. Clean Hands Count

    Medline Plus

    Full Text Available ... intended to promote or encourage adherence to CDC hand hygiene recommendations. It is a component of the Clean ... also aims to address myths and misperceptions about hand hygiene and empower patients to play a role in ...

  8. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... United States, patients get more than a million infections in the hospital while being treated for something else. The best way to help prevent infection is to practice proper hand hygiene. Hand Hygiene ...

  9. Clean Hands Count

    Medline Plus

    Full Text Available ... to CDC hand hygiene recommendations. It is a component of the Clean Hands Count campaign, which also ... views 3:56 Loading more suggestions... Show more Language: English Location: United States Restricted Mode: Off History ...

  10. Clean Hands Count

    Medline Plus

    Full Text Available ... to CDC hand hygiene recommendations. It is a component of the Clean Hands Count campaign, which also ... 3:56 Loading more suggestions... Show more Language: English Location: United States Restricted Mode: Off History Help ...

  11. Clean Hands Count

    Medline Plus

    Full Text Available ... LIVES - Clean Your Hands - No action today; no cure tomorrow - Duration: 3:10. World Health Organization 59, ... 328 views 1:53 Good Sam Hand Hygiene Music Video - Duration: 2:28. Good Samaritan Medical Center ...

  12. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... public health professionals. More > Hand Hygiene Saves Lives (5:10) Recommend on Facebook Tweet Share Compartir Hand ... High resolution [22.9 MB] Open Captioned [14.5 MB] Request a higher resolution file Copy the ...

  13. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... hospital while being treated for something else. The best way to help prevent infection is to practice proper hand hygiene. Hand Hygiene Saves Lives shows how patients can play an active role in reminding healthcare ...

  14. Hand Hygiene Saves Lives

    Medline Plus

    Full Text Available ... Please Parents Want To Do What′s Best The Obesity Epidemic Outbreaks CDC: Protecting Americans through Global Health ... best way to help prevent infection is to practice proper hand hygiene. Hand Hygiene Saves Lives shows ...

  15. Arthritis of the Hand

    Science.gov (United States)

    .org Arthritis of the Hand Page ( 1 ) The hand and wrist have multiple small joints that work together to ... a shoelace. When the joints are affected by arthritis, activities of daily living can be difficult. Arthritis ...

  16. Clean Hands Count

    Medline Plus

    Full Text Available ... next. Up next Wash your Hands - it just makes sense. - Duration: 1:36. Seema Marwaha 335,368 views 1:36 WHO: SAVE LIVES - Clean Your Hands - No action today; no cure tomorrow - ...

  17. Fish eye optics

    Science.gov (United States)

    Hudec, R.; Michalova, S.

    2017-07-01

    We report on small student (high—school) project of the Czech Academy of Sciences dealing with animal (fish) eyes and possible application in science and technology. Albeit most fishes have refractive eyes, the recent discoveries confirm that some fishes have reflective eyes with strange arrangements as well.

  18. About the Eye

    Medline Plus

    Full Text Available ... other programs with respect to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health ... Eye Ask a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and ...

  19. Common eye emergencies

    African Journals Online (AJOL)

    2007-10-11

    Oct 11, 2007 ... Common eye emergencies may present as an acute red eye, sudden visual loss or acute ocular trauma. Most eye emergencies will require referral to an ophthalmologist after initial basic examination and primary management. A relevant history of onset and symptoms of the current problem must be ...

  20. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Global Ophthalmology Guide Eye Health Find an Ophthalmologist Academy Store Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News ... For Advertisers For Media Ophthalmology Job Center © American Academy of Ophthalmology 2017 Our Sites EyeWiki International Society of Refractive Surgery ... Enter code: * Message: Thank you Your feedback has been sent.

  1. The all seeing eye?

    NARCIS (Netherlands)

    Koenderink, Jan J.|info:eu-repo/dai/nl/070864543

    2014-01-01

    The All Seeing Eye? Did you know that you are probably a believer in the All Seeing Eye? The odds are that I’m right—why? Well, the bulk of mainstream vision literature blindly relies on the All Seeing Eye. It is written all over papers, albeit between the lines. Understandably so, for scientists

  2. Clean Hands Count

    Medline Plus

    Full Text Available ... Moments of Hand Hygiene - Duration: 1:53. Salem Health 11,700 views 1:53 Good Sam Hand Hygiene Music Video - Duration: 2:28. Good Samaritan Medical Center 2,398 views 2:28 Hand Hygiene Saves Lives - Duration: 5:12. ... 1:38 Hand Hygiene for Health Care Workers - Germ Smart - Duration: 5:45. Former ...

  3. Hand hygiene strategies

    OpenAIRE

    Yazaji, Eskandar Alex

    2011-01-01

    Hand hygiene is one of the major players in preventing healthcare associated infections. However, healthcare workers compliance with hand hygiene continues to be a challenge. This article will address strategies to help improving hand hygiene compliance. Keywords: hand hygiene; healthcare associated infections; multidisciplinary program; system change; accountability; education; feedback(Published: 18 July 2011)Citation: Journal of Community Hospital Internal Medicine Perspectives 2011, 1: 72...

  4. Clean Hands Count

    Medline Plus

    Full Text Available ... Wash your Hands - it just makes sense. - Duration: 1:36. Seema Marwaha 353,242 views 1:36 Wash 'Em - Hand Hygiene Music Video - Duration: ... 3:10 Hand Washing Technique - WHO Approved - Duration: 1:19. AllYouWantTV 632,779 views 1:19 5 ...

  5. Hand x-ray

    Science.gov (United States)

    X-ray - hand ... A hand x-ray is taken in a hospital radiology department or your health care provider's office by an ... technician. You will be asked to place your hand on the x-ray table, and keep it ...

  6. Robotic hand and fingers

    Science.gov (United States)

    Salisbury, Curt Michael; Dullea, Kevin J.

    2017-06-06

    Technologies pertaining to a robotic hand are described herein. The robotic hand includes one or more fingers releasably attached to a robotic hand frame. The fingers can abduct and adduct as well as flex and tense. The fingers are releasably attached to the frame by magnets that allow for the fingers to detach from the frame when excess force is applied to the fingers.

  7. Guideline Implementation: Hand Hygiene.

    Science.gov (United States)

    Goldberg, Judith L

    2017-02-01

    Performing proper hand hygiene and surgical hand antisepsis is essential to reducing the rates of health care-associated infections, including surgical site infections. The updated AORN "Guideline for hand hygiene" provides guidance on hand hygiene and surgical hand antisepsis, the wearing of fingernail polish and artificial nails, proper skin care to prevent dermatitis, the wearing of jewelry, hand hygiene product selection, and quality assurance and performance improvement considerations. This article focuses on key points of the guideline to help perioperative personnel make informed decisions about hand hygiene and surgical hand antisepsis. The key points address the necessity of keeping fingernails and skin healthy, not wearing jewelry on the hands or wrists in the perioperative area, properly performing hand hygiene and surgical hand antisepsis, and involving patients and visitors in hand hygiene initiatives. Perioperative RNs should review the complete guideline for additional information and for guidance when writing and updating policies and procedures. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.

  8. Clean Hands Count

    Medline Plus

    Full Text Available ... 574 views 3:40 Proper Hand Washing For Nurses - Duration: 2:57. Kevin Gorin 221,991 views 2:57 A very serious message about hand hygiene in hospitals - Duration: 3:51. seriousaboutHAI 130,444 views 3:51 Hand Hygiene for Health Care Workers - Germ Smart - Duration: 5:45. Former Saskatoon ...

  9. Clean Hands Count

    Medline Plus

    Full Text Available ... today; no cure tomorrow - Duration: 3:10. World Health Organization 61,636 views 3:10 Hand Washing ... 51 5 videos Play all Hand washing 2018 health.services health.services Wash 'Em - Hand Hygiene Music ...

  10. Eye Care: MedlinePlus Health Topic

    Science.gov (United States)

    ... Institute) Sports and Your Eyes (National Eye Institute) Topic Image MedlinePlus Email Updates Get Eye Care updates by email What's this? GO Related Health Topics Eye Diseases Eye Infections Eye Injuries Eye Wear ...

  11. School eye health appraisal

    Directory of Open Access Journals (Sweden)

    Desai Sanjiv

    1989-01-01

    Full Text Available School children form an important large target group which must be screened adequately for early detection of eye diseases and prevention of blindness. A total approach in a school eye health programme must include teacher orientation and health education of children in addition to screening for eye diseases. The ocular morbidity pattern in 5135 school children of Jodhpur is discussed in this paper and it is hoped that it will be an indicator to all eye care agencies to help plan their priorities in the delivery of school based eye care.

  12. Evaluation von chirurgischem Koordinationstraining [Evaluation of surgical coordination

    Directory of Open Access Journals (Sweden)

    Schneider, Joachim H.

    2007-02-01

    Full Text Available [english] The eye-hand coordination is important in the use of monitors performing successfully diagnostic and therapeutic procedures. It is necessary to interpret the screen on the monitor anatomical correctly in order to coordinate instruments without the intention of depth. The Tübinger Skills Trainer (TST was manufactured not only for great cohorts of students but also to evaluate manual skills without great numbers of controllers. Younger and senor students and younger surgeons were studied. Mistakes and time duration were registered by the PC. In the group of the students mistakes and time durations were decreased in the second trial. Therefore the measuring of the training effect is objective. In the third group the training with both hands showed a diminished time space but an increase of the mistakes. The Tübinger Sills Trainer was fully accepted by students and is reliable to use it for medical education. [german] Die Augen-Hand Koordination ist beim Einsatz von Monitoren in Diagnostik und Therapie von entscheidender Bedeutung für den angestrebten Erfolg. Dabei muss das zweidimensionale Monitorbild anatomisch korrekt interpretiert und der Einsatz von Instrumenten bei fehlender Tiefenwahrnehmung koordiniert werden. Der Tübinger Geschicklichkeitstrainer wurde für große Studentenkohorten nicht nur für ein Basistraining zur Erlangung von manuellen Fertigkeiten entwickelt, sondern auch um diese mit geringem Dozentenaufwand evaluieren zu können. Bei insgesamt 125 Studienteilnehmern wurde ein einhändiges und beidhändiges chirurgisches Basistraining für Medizinstudenten in verschiedenen Ausbildungsstadien und Ärzten in der chirurgischen Weiterbildung durchgeführt. Als Variablen wurden Fehlerquote und Zeitbedarf computergestützt aufgezeichnet. Bei Studenten und PJ Studenten sanken Fehlerzahl und Zeitbedarf beim einhändigen und beidhändigen Training im zweiten Durchgang. Damit konnte ein Trainingserfolg objektiviert werden. In

  13. Reversal of Handedness Effects on Bimanual Coordination in Adults with Down Syndrome

    Science.gov (United States)

    Mulvey, G. M.; Ringenbach, S. D. R.; Jung, M. L.

    2011-01-01

    Background: Research on unimanual tasks suggested that motor asymmetries between hands may be reduced in people with Down syndrome. Our study examined handedness (as assessed by hand performance) and perceptual-motor integration effects on bimanual coordination. Methods: Adults with Down syndrome (13 non-right-handed, 22 right-handed), along with…

  14. [Integration of Injured Hands].

    Science.gov (United States)

    Winkel, Reiner

    2017-02-01

    Any injury of a hand more or less disintegrates the injured hand. The rehabilitation of an alienated hand is prolonged. How can the alienation of the own but injured hand and the involuntary and unconscious inhibition of its perception and use be diagnosed, explained, avoided and designated? Medical observations and interviews with patients and therapists on the occasion of rehabilitation of hand injuries resulted in the development of a new concept of biopsychosocial integrating rehabilitation and a creative hand therapy with the objective of integrating injured and alienated hands. The inhibition of the gesture of thinking has been the most revealing sign for the diagnosis of a disintegration of an injured hand. Explanation: The involuntary inhibition to recognize and use an injured hand causes and implicates the alienation of the rested hand. Information by hand surgeons and hand therapists. Creative hand therapy guides the attention to complex and pleasing activities. In complex disintegrations after hand injuries the hand as well as the person need help. Designation: Hypotheses: Posttraumatic Proportionate Regional Disintegration while the tissues heal. Posttraumatic Complex Regional Disintegration, if the disintegration overruns the healing of tissues or if the person suffers. The Complex Regional Pain Syndrome is distinguished as a rare exception of a biopsychosocial disintegration. Posttraumatic regional disintegration seems to be proportionate while the tissues are healing. If the mentioned sensations of the patients and the visible signs of disintegration persist, the disorder spreads onto the biopsychosocial unit of the person. This disorder of hand and person may be designated as a complex disorder. The impact of a proportionate posttraumatic disintegration as well as the formation and exacerbation of a complex posttraumatic disintegration may be prevented by the facilitation of the integration of an injured hand. Scientific prove is needed for: the

  15. Hand Hygiene Saves Lives

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  16. Eye and head movements shape gaze shifts in Indian peafowl.

    Science.gov (United States)

    Yorzinski, Jessica L; Patricelli, Gail L; Platt, Michael L; Land, Michael F

    2015-12-01

    Animals selectively direct their visual attention toward relevant aspects of their environments. They can shift their attention using a combination of eye, head and body movements. While we have a growing understanding of eye and head movements in mammals, we know little about these processes in birds. We therefore measured the eye and head movements of freely behaving Indian peafowl (Pavo cristatus) using a telemetric eye-tracker. Both eye and head movements contributed to gaze changes in peafowl. When gaze shifts were smaller, eye movements played a larger role than when gaze shifts were larger. The duration and velocity of eye and head movements were positively related to the size of the eye and head movements, respectively. In addition, the coordination of eye and head movements in peafowl differed from that in mammals; peafowl exhibited a near-absence of the vestibulo-ocular reflex, which may partly result from the peafowl's ability to move their heads as quickly as their eyes. © 2015. Published by The Company of Biologists Ltd.

  17. Brain activation during manipulation of the myoelectric prosthetic hand: a functional magnetic resonance imaging study.

    Science.gov (United States)

    Maruishi, Masaharu; Tanaka, Yoshiyuki; Muranaka, Hiroyuki; Tsuji, Toshio; Ozawa, Yoshiaki; Imaizumi, Satoshi; Miyatani, Makoto; Kawahara, Junichiro

    2004-04-01

    Neuroimaging data, particularly functional magnetic resonance imaging (fMRI) findings, have not been reported in users of the myoelectric or electromyographic (EMG) prosthetic hand. We developed a virtual EMG prosthetic hand system to eliminate mutual signal noise interference between fMRI imaging and the EMG prosthesis. We used fMRI to localize activation in the human brain during manipulation of the virtual EMG prosthetic hand. Fourteen right-handed normal subjects were instructed to perform repetitive grasping with the right hand with eyes closed (CEG); repetitive grasping with the right hand with eyes open to obtain visual feedback of their own hand movement (OEG); and repetitive grasping with the virtual EMG prosthetic hand with the eyes open to obtain visual feedback of the prosthetic hand movement (VRG). The specific site activated during manipulation of the EMG prosthetic hand was the right ventral premotor cortex. Both paradigms with visual feedback also (OEG and VRG) demonstrated activation in the right posterior parietal cortex. The center of activation of the right posterior parietal cortex shifted laterally for visual feedback with the virtual EMG prosthetic hand compared to a subject's own hand. The results suggest that the EMG prosthetic hand might be recognized in the brain as a high-performance alternative to a real hand, being controlled through a "mirror system" in the brain.

  18. Motor synergies for dampening hand vibration during human walking.

    Science.gov (United States)

    Togo, Shunta; Kagawa, Takahiro; Uno, Yoji

    2012-01-01

    This study investigated the motion required to carry a cup filled with water without spilling it, which is a common human dexterous task. This task requires the individual to dampen hand vibration while walking. We hypothesize that a reduction in hand jerk and a constant cup angle are required to achieve this task. We measured movements while human subjects carried a cup with water (WW task) and with stones (WS task) using a three-dimensional position measurement system and then analyzed joint coordination. We empirically confirmed that the value of hand jerk and the variance in cup angle in the WW task were smaller than those in the WS task. We used uncontrolled manifold (UCM) analysis to quantify joint coordination corresponding to the motor synergy required to reduce the hand jerk and variance of the cup angle. UCM components, which did not affect the hand jerk and cup angle, were larger than orthogonal components, which directly affected the hand jerk and cup angle in the WW task. These results suggest that there is a coordinated control mechanism that reduces hand jerk and maintains a constant cup angle when carrying a cup filled with water without spilling it. In addition, we suggest that humans adopt a flexible and coordinated control strategy of allowing variance independent of the variables that should be controlled to achieve this dexterous task.

  19. Movement coordination during conversation.

    Directory of Open Access Journals (Sweden)

    Nida Latif

    Full Text Available Behavioral coordination and synchrony contribute to a common biological mechanism that maintains communication, cooperation and bonding within many social species, such as primates and birds. Similarly, human language and social systems may also be attuned to coordination to facilitate communication and the formation of relationships. Gross similarities in movement patterns and convergence in the acoustic properties of speech have already been demonstrated between interacting individuals. In the present studies, we investigated how coordinated movements contribute to observers' perception of affiliation (friends vs. strangers between two conversing individuals. We used novel computational methods to quantify motor coordination and demonstrated that individuals familiar with each other coordinated their movements more frequently. Observers used coordination to judge affiliation between conversing pairs but only when the perceptual stimuli were restricted to head and face regions. These results suggest that observed movement coordination in humans might contribute to perceptual decisions based on availability of information to perceivers.

  20. The Avocado Hand

    LENUS (Irish Health Repository)

    Rahmani, G

    2017-11-01

    Accidental self-inflicted knife injuries to digits are a common cause of tendon and nerve injury requiring hand surgery. There has been an apparent increase in avocado related hand injuries. Classically, the patients hold the avocado in their non-dominant hand while using a knife to cut\\/peel the fruit with their dominant hand. The mechanism of injury is usually a stabbing injury to the non-dominant hand as the knife slips past the stone, through the soft avocado fruit. Despite their apparent increased incidence, we could not find any cases in the literature which describe the “avocado hand”. We present a case of a 32-year-old woman who sustained a significant hand injury while preparing an avocado. She required exploration and repair of a digital nerve under regional anaesthesia and has since made a full recovery.

  1. A natural approach to convey numerical digits using hand activity recognition based on hand shape features

    Science.gov (United States)

    Chidananda, H.; Reddy, T. Hanumantha

    2017-06-01

    This paper presents a natural representation of numerical digit(s) using hand activity analysis based on number of fingers out stretched for each numerical digit in sequence extracted from a video. The analysis is based on determining a set of six features from a hand image. The most important features used from each frame in a video are the first fingertip from top, palm-line, palm-center, valley points between the fingers exists above the palm-line. Using this work user can convey any number of numerical digits using right or left or both the hands naturally in a video. Each numerical digit ranges from 0 to9. Hands (right/left/both) used to convey digits can be recognized accurately using the valley points and with this recognition whether the user is a right / left handed person in practice can be analyzed. In this work, first the hand(s) and face parts are detected by using YCbCr color space and face part is removed by using ellipse based method. Then, the hand(s) are analyzed to recognize the activity that represents a series of numerical digits in a video. This work uses pixel continuity algorithm using 2D coordinate geometry system and does not use regular use of calculus, contours, convex hull and datasets.

  2. Culture change for hand hygiene: clean hands save lives, part II.

    Science.gov (United States)

    Fitzpatrick, Kimberley R; Pantle, Annette C; McLaws, Mary-Louise; Hughes, Clifford F

    2009-10-19

    To present the results of surveys of staff, patients and visitors about their perceptions of hand hygiene behaviour before and after implementation of the Clean hands save lives campaign in New South Wales public hospitals. Pre- and post-campaign questionnaires, disseminated through project officers in each health authority, were completed by selected staff and patients/visitors in all 208 public hospitals in NSW. Combined, de-identified results for each health authority were forwarded to the NSW Clinical Excellence Commission for analysis. Awareness of campaign material; staff perceptions about their ability to maintain a high level of hand hygiene compliance before and after contact with patients; compliance self-reported by staff compared with compliance perceived by patients/visitors and compliance assessed by overt observation. Most staff and patients/visitors were aware of campaign materials. Eighty-six per cent of staff respondents (495/578) believed that placement of alcohol-based hand rub (AHR) close to the point of patient care had improved hand hygiene compliance, and 76% (510/671) believed they could sustain their level of compliance. Only 1 in 4 patients or visitors (106/397) were willing to question health care workers who appeared not to be complying with hand hygiene practices. As the first coordinated statewide campaign to modify hand hygiene culture, the Clean hands save lives campaign successfully engendered positive attitudes and dispelled negative perceptions about the onerous nature of before- and after-patient-contact hand hygiene compliance.

  3. Implants in the hand; Implantate der Hand

    Energy Technology Data Exchange (ETDEWEB)

    Wanivenhaus, A. [Medizinische Universitaet, Universitaetsklinik fuer Orthopaedie, Wien (Austria)

    2006-09-15

    Increasingly, implants in the region of hand joints and the wrist represent an alternative for the treatment of post-traumatic, inflamed, or degenerative joint damage. The diversity of hand functions also results in varied solutions, which are effective in their stability, mobility, and distraction. Different materials are necessary for this, and they require subtile radiological control. The native X-ray represents the substantial method to observe migration of the implants. Each interface between titanium, ceramic, zirconium, pyrocarbon, and silicon to the bone has to be assessed differently in order to obtain a relevant statement. The finger joints and to a limited extent the wrist represent the artificial joints with limited alternative therapy. Other implants in the hand should only be applied after strict indication and patient compliance, as arthrodesis and resection arthroplasty have shown very good long-term results. (orig.) [German] Implantate im Bereich der Gelenke der Hand und des Handgelenks stellen zunehmend Alternativen bei der Versorgung posttraumatischer, entzuendlicher oder degenerativer Gelenkschaeden dar. Die Vielfalt der Handfunktionen fuehrt auch zu unterschiedlichen Loesungen, die durch Stabilitaet, Mobilitaet und Distraktion wirksam werden. Dafuer sind unterschiedliche Materialien erforderlich, die eine subtile radiologische Kontrolle erfordern. Das Nativroentgen stellt das wesentlichste Verfahren zur Verlaufsbeobachtung von Implantaten dar. Das Interface zwischen Titan, Keramik, Zirkonium, Pyrokarbon und Silikon zum Knochen muss unterschiedlich bewertet werden, um relevante Aussagen treffen zu koennen. Die Fingergelenke und in begrenztem Ausmass auch das Handgelenk stellen Kunstgelenke mit geringen Alternativtherapiemoeglichkeiten dar. Die uebrigen Implantate der Hand sollten nur bei strenger Indikationsstellung und hoher Patientencompliance Anwendung finden, da Arthrodese oder Resektionsarthroplastik gute Langzeitresultate aufweisen. (orig.)

  4. The 'scanning hypothesis' of rapid eye movements during REM sleep: a review of the evidence.

    Science.gov (United States)

    Arnulf, I

    2011-12-01

    Rapid eye movements (REMs) and visual dreams are salient features of REM sleep. However, it is unclear whether the eyes scan dream images. Several lines of evidence oppose the scanning hypothesis: REMs persist in animals and humans without sight (pontine cats, foetus, neonates, born-blinds), some binocular REMs are not conjugated (no focus point), REMs occur in parallel (not in series) with the stimulation of the visual cortex by ponto-geniculo-occipital spikes, and visual dreams can be obtained in non REM sleep. Studies that retrospectively compared the direction of REMs to dream recall recorded after having awakened the sleeper yielded inconsistent results, with a concordance varying from 9 to 80%. However, this method was subject to methodological flaws, including the bias of retrospection and neck atonia that does not allow the determination of the exact direction of gaze. Using the model of RBD (in which patients are able to enact their dreams due to the absence of muscle atonia) in 56 patients, we directly determined if the eyes moved in the same directions as the head and limbs. When REMs accompanied goal-oriented motor behaviour during RBD (e.g., framing something, greeting with the hand, climbing a ladder), 90% were directed towards the action of the patient (same plane and direction). REMs were however absent in 38% of goal-oriented behaviours. This directional coherence between limbs, head and eye movements during RBD suggests that, when present, REMs imitate the scanning of the dream scene. Because REMs index and complexity were similar in patients with RBD and controls, this concordance can be extended to normal REM sleep. These results are consistent with the model of a brainstem generator activating simultaneously images, sounds, limbs movements and REMs in a coordinated parallel manner, as in a virtual reality.

  5. Osteomyelitis of the hand.

    Science.gov (United States)

    Pinder, R; Barlow, G

    2016-05-01

    Osteomyelitis of the hand is uncommon, but if not adequately and promptly treated the detrimental effects on hand function can be devastating. The majority of literature on osteomyelitis relates to the lower limb, but the principles of management are applicable to the hand, with good surgical debridement and culture-guided antimicrobial therapy. For osteomyelitis in general, antibiotic therapy of 4-6 weeks' duration (intravenous and/or oral) is typically recommended. In the hand, length and mode of antibiotic administration are still under study. V. © The Author(s) 2015.

  6. Modern sports eye injuries.

    Science.gov (United States)

    Capão Filipe, J A; Rocha-Sousa, A; Falcão-Reis, F; Castro-Correia, J

    2003-11-01

    To determine the severity and long term sequelae of eye injuries caused by modern sports that could be responsible for significant ocular trauma in the future. Prospective observational study of 24 (25 eyes) athletes with sports related ocular injuries from health clubs, war games, adventure, radical and new types of soccer, presenting to an eye emergency department between 1992 and 2002 (10 years). Modern sports were responsible for 8.3% of the 288 total sports eye injuries reported. Squash (29.2%) was the most common cause, followed by paintball (20.8%) and motocross (16.6%). The most common diagnosis during the follow up period was retinal breaks (20%). 18 (75%) patients sustained a severe injury. The final visual acuity remained paintball players. Ocular injuries resulting from modern sports are often severe. Adequate instruction of the participants in the games, proper use of eye protectors, and a routine complete ophthalmological examination after an eye trauma should be mandatory.

  7. The eyes as a mirror of our thoughts: quantification of motor imagery of goal-directed movements through eye movement registration.

    Science.gov (United States)

    Heremans, Elke; Helsen, Werner F; Feys, Peter

    2008-03-05

    It has been suggested that motor imagery possesses a range of useful applications in sport as well as in rehabilitation. Until now, research in this field has been hampered by the lack of an objective method to monitor the subjects' participation in the task. In this present study, a new approach to quantifying motor imagery of goal-directed hand movements by means of eye movement registration is examined. Eye movements of 15 right-handed subjects were recorded using EOG during both physical execution and visual motor imagery of a cyclical aiming task, performed at three different inter-target distances. We found that 89% of subjects made task-related eye movements during imagery with the eyes open and 84% of participants also did so during imagery with the eyes closed. Both the number and amplitude of the eye movements during imagery closely resembled those of eye movements made during physical execution of the task. This indicates that the coupling between neural patterns for eye and hand movements remains intact when hand movements are merely imagined as opposed to being physically executed. Therefore, eye movement recordings may be used as an objective technique to evaluate subjects' compliance, motor imagery ability, and spatial accuracy.

  8. Human eye-head gaze shifts preserve their accuracy and spatiotemporal trajectory profiles despite long-duration torque perturbations that assist or oppose head motion.

    Science.gov (United States)

    Boulanger, Mathieu; Galiana, Henrietta L; Guitton, Daniel

    2012-07-01

    Humans routinely use coordinated eye-head gaze saccades to rapidly and accurately redirect the line of sight (Land MF. Vis Neurosci 26: 51-62, 2009). With a fixed body, the gaze control system combines visual, vestibular, and neck proprioceptive sensory information and coordinates two moving platforms, the eyes and head. Classic engineering tools have investigated the structure of motor systems by testing their ability to compensate for perturbations. When a reaching movement of the hand is subjected to an unexpected force field of random direction and strength, the trajectory is deviated and its final position is inaccurate. Here, we found that the gaze control system behaves differently. We perturbed horizontal gaze shifts with long-duration torques applied to the head that unpredictably either assisted or opposed head motion and very significantly altered the intended head trajectory. We found, as others have with brief head perturbations, that gaze accuracy was preserved. Unexpectedly, we found also that the eye compensated well--with saccadic and rollback movements--for long-duration head perturbations such that resulting gaze trajectories remained close to that when the head was not perturbed. However, the ocular compensation was best when torques assisted, compared with opposed, head motion. If the vestibuloocular reflex (VOR) is suppressed during gaze shifts, as currently thought, what caused invariant gaze trajectories and accuracy, early eye-direction reversals, and asymmetric compensations? We propose three mechanisms: a gaze feedback loop that generates a gaze-position error signal; a vestibular-to-oculomotor signal that dissociates self-generated from passively imposed head motion; and a saturation element that limits orbital eye excursion.

  9. What Is Dry Eye?

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    Full Text Available ... Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & ...

  10. What Is Dry Eye?

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    Full Text Available ... Member Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & ...

  11. Ocular Emergencies: Red Eye.

    Science.gov (United States)

    Tarff, Andreina; Behrens, Ashley

    2017-05-01

    "Red eye" is used as a general term to describe irritated or bloodshot eyes. It is a recognizable sign of an acute/chronic, localized/systemic underlying inflammatory condition. Conjunctival injection is most commonly caused by dryness, allergy, visual fatigue, contact lens overwear, and local infections. In some instances, red eye can represent a true ocular emergency that should be treated by an ophthalmologist. A comprehensive assessment of red eye conditions is required to preserve the patients visual function. Severe ocular pain, significant photophobia, decreased vision, and history of ocular trauma are warning signs demanding immediate ophthalmological consultation. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. What Is Dry Eye?

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    Full Text Available ... Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics ... Services Advocacy Foundation About Subspecialties & More Eye ...

  13. What Is Dry Eye?

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    Full Text Available ... Academy Publications EyeNet Ophthalmology Ophthalmology Retina Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists ...

  14. [Hand surgery training].

    Science.gov (United States)

    Moutet, F; Haloua, J P

    2003-10-01

    Training of the hand surgeon HAND SURGEON A CONCEPT: The hand surgeon is supposed to be in charge of all the hand lesions regarding, skeleton, muscles, tendons, nerves and vessels. He has to be able to insure reparation and coverage of all of them. So he is involved in all the structures, which insure integrity and function of the hand. PURPOSE AND WAYS OF TRAINING: To obtain the asked ability, the hand surgeon training has to be global and sustained by two underlying surgical specialities: orthopedic surgery and plastic and reconstructive surgery. From 2000 after many years of dealings, a Right to the Title in Hand Surgery was born. This Right to the Title wants to be the formal recognition of the specific training of the hand surgeon. For the well-recognized ancient hand surgeons they need to be confirmed by one's peers. Now a day the hand surgeon has to satisfy to this specific training: Passed the complete training and exam of the Orthopedic or Plastic surgery board. Spent at least 6 months as resident in the other underlying specialty. Passed a microsurgery examination. Passed one of the four national Hand Surgery diplomas (DIU/Inter-Universitary Diploma). The examinations have been harmonized. A common formation is delivered regarding hand surgery, the way of examination is the same and the formation is 2 years long. The final exam is presented in front of board of examiners where a teacher of one of the other three national diplomas is present. Spent at least 2 years in a formative hand surgery unit, listed by the French College of Hand Surgeons, as senior surgeon. Those requirements are heavy to assume and need a heavy personal involvement. That seems to be necessary to have an ability level as high as possible. Emergency surgery practice is absolutely necessary in this training. All the 17 university formative hand surgery units listed by the French College of Hand Surgeons are members of the FESUM (European Federation of the Emergency Hand Units

  15. Eye movements may cause motor contagion effects.

    Science.gov (United States)

    Constable, Merryn D; de Grosbois, John; Lung, Tiffany; Tremblay, Luc; Pratt, Jay; Welsh, Timothy N

    2017-06-01

    When a person executes a movement, the movement is more errorful while observing another person's actions that are incongruent rather than congruent with the executed action. This effect is known as "motor contagion". Accounts of this effect are often grounded in simulation mechanisms: increased movement error emerges because the motor codes associated with observed actions compete with motor codes of the goal action. It is also possible, however, that the increased movement error is linked to eye movements that are executed simultaneously with the hand movement because oculomotor and manual-motor systems are highly interconnected. In the present study, participants performed a motor contagion task in which they executed horizontal arm movements while observing a model making either vertical (incongruent) or horizontal (congruent) movements under three conditions: no instruction, maintain central fixation, or track the model's hand with the eyes. A significant motor contagion-like effect was only found in the 'track' condition. Thus, 'motor contagion' in the present task may be an artifact of simultaneously executed incongruent eye movements. These data are discussed in the context of stimulation and associative learning theories, and raise eye movements as a critical methodological consideration for future work on motor contagion.

  16. Clean Hands Count

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    Full Text Available ... AllYouWantTV 616,527 views 1:19 WHO: SAVE LIVES - Clean Your Hands - No action today; no cure ... 10,684 views 1:53 Clean hands save lives - Duration: 0:59. NIHClinicalCenter 2,298 views 0: ...

  17. Hand measuring eqipment

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This note is used in connection with a 3 x 2 hours laboratory exercise as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The laboratory includes a demonstration of a series of hand measuring tools as well as a number of exercises, illustrating the use of hand measuring equipment...

  18. HAND INJURIES IN VOLLEYBALL

    NARCIS (Netherlands)

    BHAIRO, NH; NIJSTEN, MWN; VANDALEN, KC; TENDUIS, HJ

    We studied the long-term sequelae of hand injuries as a result of playing volleyball. In a retrospective study, 226 patients with injuries of the hand who were seen over a 5-year period at our Trauma Department, were investigated. Females accounted for 66 % of all injuries. The mean age was 26

  19. Clean Hands Count

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    Full Text Available ... University & Jefferson Health 402,107 views 5:46 Germ Smart - Wash Your Hands! - Duration: 4:50. Former ... 1:53 Hand Hygiene for Health Care Workers - Germ Smart - Duration: 5:45. Former Saskatoon Health Region ...

  20. Hand Hygiene Saves Lives

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    Full Text Available ... than a million infections in the hospital while being treated for something else. The best way to help prevent infection is to practice proper hand hygiene. Hand Hygiene Saves Lives shows how patients can play an active role ...

  1. Clean Hands Count

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    Full Text Available ... 041 views 3:51 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Thomas Jefferson University & Jefferson ... 851 views 5:12 Good Sam Hand Hygiene Music Video - Duration: 2:28. Good Samaritan Medical Center ...

  2. Clean Hands Count

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    Full Text Available ... 257 views 3:10 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Thomas Jefferson University & Jefferson ... 039 views 3:38 Good Sam Hand Hygiene Music Video - Duration: 2:28. Good Samaritan Medical Center ...

  3. Clean Hands Count

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  4. Clean Hands Count

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    Full Text Available ... is a component of the Clean Hands Count campaign, which also aims to address myths and misperceptions ... views 3:56 Creative Communication - LifeBouy Hand Washing Campaign - Duration: 2:08. LIQVD ASIA 15,338 views ...

  5. Clean Hands Count

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    Full Text Available ... health.services health.services Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Thomas Jefferson University & Jefferson ... 700 views 1:53 Good Sam Hand Hygiene Music Video - Duration: 2:28. Good Samaritan Medical Center ...

  6. Tropical Diabetic Hand Syndrome

    African Journals Online (AJOL)

    Any adult with DM in the tropics with hand cellulitis, infection and gangrene qualifies for TDHS.[1-4] It is a terminology used to describe a specific acute symptom complex found in diabetic patients in the tropics usually follows minor trauma to the hand and associated with progressive synergistic form of gangrene.

  7. Clean Hands Count

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    Full Text Available ... today; no cure tomorrow - Duration: 3:10. World Health Organization 56,897 views 3:10 Handwashing Gangnam ... Moments of Hand Hygiene - Duration: 1:53. Salem Health 10,662 views 1:53 Clean hands save ...

  8. Clean Hands Count

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    Full Text Available ... no cure tomorrow - Duration: 3:10. World Health Organization 60,515 views 3:10 Hand Washing Technique - ... soap and water - Duration: 1:27. World Health Organization 155,252 views 1:27 Good Sam Hand ...

  9. Clean Hands Count

    Science.gov (United States)

    ... 05 Hand Hygiene for Health Care Workers - Germ Smart - Duration: 5:45. Former Saskatoon Health Region 71,984 views 5:45 WHO: How to handwash? With soap and water - Duration: 1:27. World Health Organization 155,252 views 1:27 Good Sam Hand ...

  10. Clean Hands Count

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    Full Text Available ... 05 Hand Hygiene for Health Care Workers - Germ Smart - Duration: 5:45. Former Saskatoon Health Region 71,984 views 5:45 WHO: How to handwash? With soap and water - Duration: 1:27. World Health Organization 155,252 views 1:27 Good Sam Hand ...

  11. Clean Hands Count

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    Full Text Available ... hand hygiene and empower patients to play a role in their care by asking or reminding healthcare ... World Health Organization 48,051 views 1:19 Role play done by Oman AlKhair Hospital on Hand ...

  12. Clean Hands Count

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    Full Text Available ... 002 views 3:51 Wash 'Em - Hand Hygiene Music Video - Duration: 5:46. Thomas Jefferson University & Jefferson ... 269 views 1:38 Good Sam Hand Hygiene Music Video - Duration: 2:28. Good Samaritan Medical Center ...

  13. Clean Hands Count

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    Full Text Available ... Up next Wash your Hands - it just makes sense. - Duration: 1:36. Seema Marwaha 335,368 views ... Kevin Gorin 217,022 views 2:57 The 5 Moments of Hand Hygiene - Duration: 1:53. Salem ...

  14. Clean Hands Count

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    Full Text Available ... no cure tomorrow - Duration: 3:10. World Health Organization 61,636 views 3:10 Hand Washing Technique - ... soap and water - Duration: 1:27. World Health Organization 167,916 views 1:27 Proper Hand Washing ...

  15. The split hand sign

    Directory of Open Access Journals (Sweden)

    Rajesh Benny

    2012-01-01

    Full Text Available Amyotrophic Lateral sclerosis (ALS is a disease characterized by pure motor asymmetric wasting of various muscles with associated upper motor neuron signs. The split hand sign, which is because of dissociated muscle weakness in the hands (thenar muscles disproportionately wasted as compared to the hypothenar muscles is a useful clinical sign for bed side diagnosis of ALS.

  16. Hand Hygiene Saves Lives

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    Full Text Available ... CDC A-Z SEARCH A B C D E F G H I J K L M ... d’Opération d’Urgence (COU) Portuguese Vacine-se e proteja-se contra o sarampo Somali Halagu Tallaalo ... Hand Hygiene Clean Hands Basics Send Us Feedback What do you think of our videos? Your feedback ...

  17. Clean Hands Count

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    Full Text Available ... Marwaha 355,166 views 1:36 Hand Washing Technique - WHO Approved - Duration: 1:19. AllYouWantTV 633,052 ... 54,858 views 1:19 NHS Hand Wash Technique - Duration: 1:17. Onclick - Bespoke Digital Learning 9, ...

  18. Clean Hands Count

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    Full Text Available ... today; no cure tomorrow - Duration: 3:10. World Health Organization 57,621 views 3:10 Healthcare Worker ... Moments of Hand Hygiene - Duration: 1:53. Salem Health 10,684 views 1:53 Hand Washing Video ...

  19. Pneumatically actuated hand tool

    NARCIS (Netherlands)

    Cool, J.C.; Rijnsaardt, K.A.

    1996-01-01

    Abstract of NL 9401195 (A) Pneumatically actuated hand tool for carrying out a mechanical operation, provided with an exchangeable gas cartridge in which the gas which is required for pneumatic actuation is stored. More particularly, the hand tool is provided with at least one pneumatic motor, at

  20. A new mapping function in table-mounted eye tracker

    Science.gov (United States)

    Tong, Qinqin; Hua, Xiao; Qiu, Jian; Luo, Kaiqing; Peng, Li; Han, Peng

    2018-01-01

    Eye tracker is a new apparatus of human-computer interaction, which has caught much attention in recent years. Eye tracking technology is to obtain the current subject's "visual attention (gaze)" direction by using mechanical, electronic, optical, image processing and other means of detection. While the mapping function is one of the key technology of the image processing, and is also the determination of the accuracy of the whole eye tracker system. In this paper, we present a new mapping model based on the relationship among the eyes, the camera and the screen that the eye gazed. Firstly, according to the geometrical relationship among the eyes, the camera and the screen, the framework of mapping function between the pupil center and the screen coordinate is constructed. Secondly, in order to simplify the vectors inversion of the mapping function, the coordinate of the eyes, the camera and screen was modeled by the coaxial model systems. In order to verify the mapping function, corresponding experiment was implemented. It is also compared with the traditional quadratic polynomial function. And the results show that our approach can improve the accuracy of the determination of the gazing point. Comparing with other methods, this mapping function is simple and valid.

  1. Hand-assisted laparoscopic sigmoid colectomy skills acquisition: augmented reality simulator versus human cadaver training models.

    Science.gov (United States)

    Leblanc, Fabien; Senagore, Anthony J; Ellis, Clyde N; Champagne, Bradley J; Augestad, Knut M; Neary, Paul C; Delaney, Conor P

    2010-01-01

    The aim of this study was to compare a simulator with the human cadaver model for hand-assisted laparoscopic colorectal skills acquisition training. An observational prospective comparative study was conducted to compare the laparoscopic surgery training models. The study took place during the laparoscopic colectomy training course performed at the annual scientific meeting of the American Society of Colon and Rectal Surgeons. Thirty four practicing surgeons performed hand-assisted laparoscopic sigmoid colectomy on human cadavers (n = 7) and on an augmented reality simulator (n = 27). Prior laparoscopic colorectal experience was assessed. Trainers and trainees completed independently objective structured assessment forms. Training models were compared by trainees' technical skills scores, events scores, and satisfaction. Prior laparoscopic experience was similar in both surgeon groups. Generic and specific skills scores were similar on both training models. Generic events scores were significantly better on the cadaver model. The 2 most frequent generic events occurring on the simulator were poor hand-eye coordination and inefficient use of retraction. Specific events were scored better on the simulator and reached the significance limit (p = 0.051) for trainers. The specific events occurring on the cadaver were intestinal perforation and left ureter identification difficulties. Overall satisfaction was better for the cadaver than for the simulator model (p = 0.009). With regard to skills scores, the augmented reality simulator had adequate qualities for the hand-assisted laparoscopic colectomy training. Nevertheless, events scores highlighted weaknesses of the anatomical replication on the simulator. Although improvements likely will be required to incorporate the simulator more routinely into the colorectal training, it may be useful in its current form for more junior trainees or those early on their learning curve. Copyright 2010 Association of Program

  2. Eye tracking social preferences

    NARCIS (Netherlands)

    Jiang, Ting; Potters, Jan; Funaki, Yukihiko

    We hypothesize that if people are motivated by a particular social preference, then choosing in accordance with this preference will lead to an identifiable pattern of eye movements. We track eye movements while subjects make choices in simple three-person distribution experiments. We characterize

  3. Photorefraction of the Eye

    Science.gov (United States)

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-01-01

    Photorefraction is a method to easily estimate the refractive state of the eye. The principle of photorefraction involves projecting light into the eye during flash photography and then examining the paths of light that emerge from the pupil after scattering on the back portion of the interior of the eyeball (fundus). We will explain the optical…

  4. What Is Dry Eye?

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    Full Text Available ... and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive Surgery Subspecialties ... and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive Surgery Subspecialties ...

  5. What Is Dry Eye?

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    Full Text Available ... Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society ... Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society ...

  6. About the Eye

    Medline Plus

    Full Text Available ... Vision Research & Ophthalmology (DIVRO) Student Training Programs To search for current job openings visit HHS USAJobs Home > NEI for Kids > About the Eye All About Vision About the Eye Ask a Scientist Video Series Glossary The Visual System Your Eyes’ ...

  7. Smoking and Eye Health

    Science.gov (United States)

    ... Patient Stories Español Eye Health / Tips & Prevention Sections Smoking and Eye Disease Leer en Español: El Cigarrillo ... By: Brenda Pagan-Duran MD Apr. 27, 2017 Smoking contributes to a number of major health problems, ...

  8. Chemotherapy in eye cancer

    African Journals Online (AJOL)

    Chemotherapy in eye cancer. Chemotherapy is one of several treatment strategies used to halt the uncontrolled division, proliferation and unpredictable growth patterns of malignant cells. R Dolland, BSc, MB BCh, FC Ophth (SA). Consultant, St John Eye Hospital, Division of Ophthalmology, Department of Neurosciences, ...

  9. About the Eye

    Medline Plus

    Full Text Available ... D., Deputy Clinical Director Education Programs National Eye Health Education Program (NEHEP) Diabetic Eye Disease Education Program Glaucoma ... NEI Office of Science Communications, Public Liaison, and Education. Technical questions ... of Health and Human Services | The National Institutes of Health | ...

  10. What Is Dry Eye?

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    Full Text Available ... Media Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare ... Media Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare ...

  11. What Is Dry Eye?

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    Full Text Available ... and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services Emergency Relief EyeCare America Help IRIS Registry Medicare ... and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services Emergency Relief EyeCare America Help IRIS Registry Medicare ...

  12. Understanding pink eye

    Science.gov (United States)

    Pink eye (PE) is a physiological tuber disorder that can result in serious processing complications and storage losses. The earliest external symptoms consist of an ephemeral pinkish discoloration around tuber eyes, predominately at the bud end of the tuber. These pinkish areas can then develop into...

  13. Perception of eye positions

    NARCIS (Netherlands)

    Lorteije, J.A.M.; Wezel, R.J.A. van; Lankheet, M.J.M.

    2002-01-01

    In a two-alternative forced-choice psychophysical test human subjects were tested for their ability to perceive their own viewing direction. A small red flash was presented at different horizontal positions left or right from the subjects' eye position on the screen. Eye positions were recorded with

  14. LASIK Eye Surgery

    Science.gov (United States)

    ... Persistent dry eyes Unstable vision due to medications, hormonal changes, pregnancy, breast-feeding or age Keratitis, uveitis, herpes simplex ... to certain conditions, such as abnormal wound healing, hormonal imbalances or pregnancy. Sometimes this change in vision is due to another eye problem, ...

  15. Eye-Tracking

    Directory of Open Access Journals (Sweden)

    Gabriela GROSSECK

    2006-01-01

    Full Text Available Eye-tracking: one of the newest and most efficient methods of improving on-line marketing communication is called eye-tracking. Marketers have borrowed this technique, usually used in psychological and medical research, in order to study web users with the help of a video camera incorporated in the monitor.

  16. What Is Dry Eye?

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    Full Text Available ... Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services Emergency Relief EyeCare America Help IRIS Registry Medicare Physician ... Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services Emergency Relief EyeCare America Help IRIS Registry Medicare Physician ...

  17. What Is Dry Eye?

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    Full Text Available ... IRIS Registry Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki ... IRIS Registry Medicare Physician Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki ...

  18. What Is Dry Eye?

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    Full Text Available ... Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare ... Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services EyeCare America Help IRIS Registry Medicare ...

  19. What Is Dry Eye?

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    Full Text Available ... Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive ... Payment Meetings and Deadlines Museum of Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive ...

  20. What Is Dry Eye?

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    Full Text Available ... Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive Surgery Subspecialties Cataract/Anterior Segment Comprehensive ... Vision Ophthalmology Job Center Our Sites EyeWiki International Society of Refractive Surgery Subspecialties Cataract/Anterior Segment Comprehensive ...

  1. About the Eye

    Medline Plus

    Full Text Available ... National Eye Institute’s mission is to “conduct and support research, training, health information dissemination, and other programs ... search for current job openings visit HHS USAJobs Home > NEI for Kids > About the Eye All About ...

  2. Handedness of children determines preferential facial and eye movements related to hemispheric specialization.

    Science.gov (United States)

    Arteaga, Carmina; Poblano, Adrián

    2008-09-01

    Despite repeated demonstrations of asymmetries in several brain functions, the biological bases of such asymmetries have remained obscure. To investigate development of lateralized facial and eye movements evoked by hemispheric stimulation in right-handed and left-handed children. Fifty children were tested according to handedness by means of four tests: I. Mono-syllabic non-sense words, II. Tri-syllabic sense words, III. Visual field occlusion by black wall, and presentation of geometric objects to both hands separately, IV. Left eye and the temporal half visual field of the right eye occlusion with special goggles, afterwards asking children to assemble a three-piece puzzle; same tasks were performed contra-laterally. Right-handed children showed higher percentage of eye movements to right side when stimulated by tri-syllabic words, while left-handed children shown higher percentages of eyes movements to left side when stimulated by the same type of words. Left-handed children spent more time in recognizing non-sense mono-syllabic words. Hand laterality correlated with tri-syllabic word recognition performance. Age contributed to laterality development in nearly all cases, except in second test. Eye and facial movements were found to be related to left- and right-hand preference and specialization for language development, as well as visual, haptic perception and recognition in an age-dependent fashion in a complex process.

  3. Right-Handed and Left-Footed? How Andrea Learned to Question the Facts.

    Science.gov (United States)

    Lord, Thomas R.

    1986-01-01

    Describes several tests for determining dominance of children's hands, eyes, feet, and thumbs. Discusses the relationship between hemispheric brain dominance and dominant sides of the body. Suggests that raising questions about generalizations can lead to new learning. (TW)

  4. Coordinate measuring machines

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceabilit...

  5. Portable eyetracking: a study of natural eye movements

    Science.gov (United States)

    Pelz, Jeff B.; Canosa, Roxanne L.; Kucharczyk, Diane; Babcock, Jason S.; Silver, Amy; Konno, Daisei

    2000-06-01

    Visual perception, operating below conscious awareness, effortlessly provides the experience of a rich representation of the environment, continuous in space and time. Conscious visual perception is made possible by the 'foveal compromise,' the combination of the high-acuity fovea and a sophisticated suite of eye movements. Our illusory visual experience cannot be understood by introspection, but monitoring eye movements lets us probe the processes of visual perception. Four tasks representing a wide range of complexity were used to explore visual perception; image quality judgments, map reading, model building, and hand-washing. Very short fixation durations were observed in all tasks, some as short as 33 msec. While some tasks showed little variation in eye movement metrics, differences in eye movement patterns and high-level strategies were observed in the model building and hand washing tasks. Performance in the hand washing task revealed a new type of eye movement. 'Planful' eye movements were made to objects well in advance of a subject's interaction with the object. Often occurring in the middle of another task, they provide 'overlapping' temporal information about the environment providing a mechanism to produce our conscious visual experience.

  6. Coordination failure caused by sunspots

    DEFF Research Database (Denmark)

    Beugnot, Julie; Gürgüç, Zeynep; Øvlisen, Frederik Roose

    2012-01-01

    In a coordination game with Pareto-ranked equilibria, we study whether a sunspot can lead to either coordination on an inferior equilibrium (mis-coordination) or to out-of equilibrium behavior (dis-coordination). While much of the literature searches for mechanisms to attain coordination on the e......In a coordination game with Pareto-ranked equilibria, we study whether a sunspot can lead to either coordination on an inferior equilibrium (mis-coordination) or to out-of equilibrium behavior (dis-coordination). While much of the literature searches for mechanisms to attain coordination...

  7. Coordinating towards a Common Good

    Science.gov (United States)

    Santos, Francisco C.; Pacheco, Jorge M.

    2010-09-01

    Throughout their life, humans often engage in collective endeavors ranging from family related issues to global warming. In all cases, the tragedy of the commons threatens the possibility of reaching the optimal solution associated with global cooperation, a scenario predicted by theory and demonstrated by many experiments. Using the toolbox of evolutionary game theory, I will address two important aspects of evolutionary dynamics that have been neglected so far in the context of public goods games and evolution of cooperation. On one hand, the fact that often there is a threshold above which a public good is reached [1, 2]. On the other hand, the fact that individuals often participate in several games, related to the their social context and pattern of social ties, defined by a social network [3, 4, 5]. In the first case, the existence of a threshold above which collective action is materialized dictates a rich pattern of evolutionary dynamics where the direction of natural selection can be inverted compared to standard expectations. Scenarios of defector dominance, pure coordination or coexistence may arise simultaneously. Both finite and infinite population models are analyzed. In networked games, cooperation blooms whenever the act of contributing is more important than the effort contributed. In particular, the heterogeneous nature of social networks naturally induces a symmetry breaking of the dilemmas of cooperation, as contributions made by cooperators may become contingent on the social context in which the individual is embedded. This diversity in context provides an advantage to cooperators, which is particularly strong when both wealth and social ties follow a power-law distribution, providing clues on the self-organization of social communities. Finally, in both situations, it can be shown that individuals no longer play a defection dominance dilemma, but effectively engage in a general N-person coordination game. Even if locally defection may seem

  8. Clean Hands Count

    Medline Plus

    Full Text Available ... reminding healthcare providers to clean their hands. See: https://www.cdc.gov/handhygiene/campa... . Comments on this ... are allowed in accordance with our comment policy: http://www.cdc.gov/SocialMedia/Tools/... This video can ...

  9. Hand Hygiene Saves Lives

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    Full Text Available ... prepared for different audiences including, children, parents, and public health professionals. More > Hand Hygiene Saves Lives (5:10) ... prepared for different audiences including, children, parents, and public health professionals. More > File Formats Help: How do I ...

  10. Clean Hands Count

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    Full Text Available ... out why Close Clean Hands Count Centers for Disease Control and Prevention (CDC) Loading... Unsubscribe from Centers for Disease Control and Prevention (CDC)? Cancel Unsubscribe Working... Subscribe ...

  11. A Myoelectric Hand Splint

    Science.gov (United States)

    Silverstein, Frances; And Others

    1974-01-01

    Development of a myoelectrically controlled hand splint permitting ambulating mobility of the user is discussed. The role of occupational therapy in the research and design of the device and the training of the patient are emphasized. (Authors)

  12. Clean Hands Count

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    Full Text Available ... makes for happy holidays Loading... Even the scrooges will smile at 3 free months of ad-free ... Autoplay When autoplay is enabled, a suggested video will automatically play next. Up next Wash your Hands - ...

  13. Clean Hands Count

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    Full Text Available ... Clean Hands Count Centers for Disease Control and Prevention (CDC) Loading... Unsubscribe from Centers for Disease Control and Prevention (CDC)? Cancel Unsubscribe Working... Subscribe Subscribed Unsubscribe 59K ...

  14. Hand Hygiene Saves Lives

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    Full Text Available ... Please Parents Want To Do What′s Best The Obesity Epidemic Outbreaks CDC: Protecting Americans through Global Health ... captioning. Videos are prepared for different audiences including, children, parents, and public health professionals. More > Hand Hygiene ...

  15. Hand Eczema: Treatment options

    DEFF Research Database (Denmark)

    Lund, Tamara Theresia; Agner, Tove

    2017-01-01

    Hand eczema is a common disease, it affects young people, is often work-related, and the burden of the disease is significant for the individual as well as for society. Factors to be considered when choosing a treatment strategy are, among others, whether the eczema is acute or chronic, the sever......Hand eczema is a common disease, it affects young people, is often work-related, and the burden of the disease is significant for the individual as well as for society. Factors to be considered when choosing a treatment strategy are, among others, whether the eczema is acute or chronic......, the severity of the disease, and the specific sub-diagnosis of hand eczema, which relates to the etiology as well as the morphology of the disease. Optimal treatment is still a challenge. This review seeks to provide an overview of the most updated treatment of hand eczema....

  16. Hand Hygiene Saves Lives

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    Full Text Available ... get more than a million infections in the hospital while being treated for something else. The best ... reminding healthcare providers to practice hand hygiene in hospitals and other healthcare facilities. Release Date: 8/4/ ...

  17. Clean Hands Count

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    Full Text Available ... Clean Hands Count Centers for Disease Control and Prevention (CDC) Loading... Unsubscribe from Centers for Disease Control and Prevention (CDC)? Cancel Unsubscribe Working... Subscribe Subscribed Unsubscribe 60K ...

  18. Hand Hygiene Saves Lives

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    Full Text Available ... Lives Wash Your Hands Physical Activity Knees Lifted High Making Health Easier: Active Living in Philadelphia, PA ... Go: Passport To Health (4:17) Vital Signs High Blood Pressure Spanish Diseases & Conditions Hablemos de la ...

  19. Clean Hands Count

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    Full Text Available ... empower patients to play a role in their care by asking or reminding healthcare providers to clean ... 290 views 1:27 Hand Hygiene for Health Care Workers - Germ Smart - Duration: 5:45. Former Saskatoon ...

  20. Osteoarthritis of the Hand

    Science.gov (United States)

    ... Therapist? Media Find a Hand Surgeon Home Anatomy Osteoarthritis Email to a friend * required fields From * To * ... for those with osteoarthritis. TREATMENT The Diagnosis of Osteoarthritis When diagnosing osteoarthritis, your doctor will ask you ...

  1. Hand Hygiene Saves Lives

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    Full Text Available ... CDC-TV videos cover a variety of health, safety and preparedness topics and include closed-captioning. Videos are prepared for different audiences including, children, parents, and public health professionals. More > Hand Hygiene ...

  2. Clean Hands Count

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    Full Text Available ... to a playlist. Sign in Share More Report Need to report the video? Sign in to report ... WHO: SAVE LIVES - Clean Your Hands - No action today; no cure tomorrow - Duration: 3:10. World Health ...

  3. Clean Hands Count

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    Full Text Available ... myths and misperceptions about hand hygiene and empower patients to play a role in their care by ... Copyright Creators Advertise Developers +YouTube Terms Privacy Policy & Safety Send feedback Test new features Loading... Working... Sign ...

  4. Second Hand Smoke: Danger

    Science.gov (United States)

    ... What's this? Submit Button Past Emails Second Hand Smoke: Danger! Recommend on Facebook Tweet Share Compartir Make ... the United States are still exposed to secondhand smoke, even though cigarette smoking rates are dropping and ...

  5. Hand eczema classification

    DEFF Research Database (Denmark)

    Diepgen, T L; Andersen, Klaus Ejner; Brandao, F M

    2008-01-01

    Summary Background Hand eczema is a long-lasting disease with a high prevalence in the background population. The disease has severe, negative effects on quality of life and sometimes on social status. Epidemiological studies have identified risk factors for onset and prognosis, but treatment...... of the disease is rarely evidence based, and a classification system for different subdiagnoses of hand eczema is not agreed upon. Randomized controlled trials investigating the treatment of hand eczema are called for. For this, as well as for clinical purposes, a generally accepted classification system...... A classification system for hand eczema is proposed. Conclusions It is suggested that this classification be used in clinical work and in clinical trials....

  6. Clean Hands Count

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    Full Text Available ... why Close Clean Hands Count Centers for Disease Control and Prevention (CDC) Loading... Unsubscribe from Centers for Disease Control and Prevention (CDC)? Cancel Unsubscribe Working... Subscribe Subscribed ...

  7. Clean Hands Count

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    Full Text Available ... Duration: 4:13. Seeker 139,093 views 4:13 Hand Hygiene from rubbing to dancing - Duration: 3:56. Hopitaux ... Loading... Loading... Loading... About Press Copyright Creators ...

  8. Clean Hands Count

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    Full Text Available ... empower patients to play a role in their care by asking or reminding healthcare providers to clean ... 584 views 1:53 Hand Hygiene for Health Care Workers - Germ Smart - Duration: 5:45. Former Saskatoon ...

  9. Clean Hands Count

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    Full Text Available ... Prevention (CDC) 199,340 views 1:04 Preventing Cancer Infections: Hand Washing - Duration: 0:57. Preventing Infections in Cancer Patients 643 views 0:57 Dettol Global Handwashing ...

  10. Hand Hygiene Saves Lives

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    Full Text Available ... Other versions: Spanish (5:10) Healthy Living Featured Videos Fight Germs. Wash Your Hands! Making Health Easier: ... Us Feedback What do you think of our videos? Your feedback about CDC-TV and our videos ...

  11. Clean Hands Count

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    Full Text Available ... Published on May 5, 2017 This video for healthcare providers is intended to promote or encourage adherence ... role in their care by asking or reminding healthcare providers to clean their hands. See: https://www. ...

  12. Clean Hands Count

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    Full Text Available ... Hands Count Centers for Disease Control and Prevention (CDC) Loading... Unsubscribe from Centers for Disease Control and Prevention (CDC)? Cancel Unsubscribe Working... Subscribe Subscribed Unsubscribe 61K Loading... ...

  13. Getting hold of approaching objects : In search of a common control of hand-closure initiation in catching and grasping

    NARCIS (Netherlands)

    van de Kamp, Cornelis; Bongers, Raoul M.; Zaal, Frank T. J. M.

    Both in the catching and grasping component of prehension, the hand opens and closes before hand-object contact is made. The initiation of hand closure has to be coordinated with the time course of the decrease of the distance between the hand and the target object, i.e., with the reaching component

  14. Fine motor skills in South African children with symptoms of ADHD: influence of subtype, gender, age, and hand dominance

    Directory of Open Access Journals (Sweden)

    Meyer Anneke

    2006-10-01

    Full Text Available Abstract Background Motor problems, often characterised as clumsiness or poor motor coordination, have been associated with ADHD in addition to the main symptom groups of inattention, impulsiveness, and overactivity. The problems addressed in this study were: (1 Are motor problems associated with ADHD symptoms, also in African cultures? (2 Are there differences in motor skills among the subtypes with ADHD symptoms? (3 Are there gender differences? (4 Is there an effect of age? (5 Are there differences in performance between the dominant and non-dominant hand? Method A total of 528 children (264 classified as having symptoms of ADHD and 264 matched comparisons of both genders and from seven different South African ethnic groups participated in the study. They were assessed with three simple, easy to administer instruments which measure various functions of motor speed and eye-hand coordination: The Grooved Pegboard, the Maze Coordination Task, and the Finger Tapping Test. The results were analysed as a function of subtype, gender, age, and hand dominance. Results The findings indicate that children with symptoms of ADHD performed significantly poorer on the Grooved Pegboard and Motor Coordination Task, but not on the Finger Tapping Test than their comparisons without ADHD symptoms. The impairment was most severe for the subtype with symptoms of ADHD-C (combined and less severe for the subtypes with symptoms of ADHD-PI (predominantly inattentive and ADHD-HI (predominantly hyperactive/impulsive. With few exceptions, both genders were equally affected while there were only slight differences in performance between the dominant and non-dominant hand. The deficiencies in motor control were mainly confined to the younger age group (6 – 9 yr. Conclusion An association between the symptoms of ADHD and motor problems was demonstrated in terms of accuracy and speed in fairly complex tasks, but not in simple motor tests of speed. This deficiency is found

  15. Smart Hand For Manipulators

    Science.gov (United States)

    Fiorini, Paolo

    1987-10-01

    Sensor based, computer controlled end effectors for mechanical arms are receiving more and more attention in the robotics industry, because commonly available grippers are only adequate for simple pick and place tasks. This paper describes the current status of the research at JPL on a smart hand for a Puma 560 robot arm. The hand is a self contained, autonomous system, capable of executing high level commands from a supervisory computer. The mechanism consists of parallel fingers, powered by a DC motor, and controlled by a microprocessor embedded in the hand housing. Special sensors are integrated in the hand for measuring the grasp force of the fingers, and for measuring forces and torques applied between the arm and the surrounding environment. Fingers can be exercised under position, velocity and force control modes. The single-chip microcomputer in the hand executes the tasks of communication, data acquisition and sensor based motor control, with a sample cycle of 2 ms and a transmission rate of 9600 baud. The smart hand described in this paper represents a new development in the area of end effector design because of its multi-functionality and autonomy. It will also be a versatile test bed for experimenting with advanced control schemes for dexterous manipulation.

  16. Advocacy for eye care

    Directory of Open Access Journals (Sweden)

    Thulasiraj D Ravilla

    2012-01-01

    Full Text Available The effectiveness of eye care service delivery is often dependant on how the different stakeholders are aligned. These stakeholders range from the ministries of health who have the capacity to grant government subsidies for eye care, down to the primary healthcare workers who can be enrolled to screen for basic eye diseases. Advocacy is a tool that can help service providers draw the attention of key stakeholders to a particular area of concern. By enlisting the support, endorsement and participation of a wider circle of players, advocacy can help to improve the penetration and effectiveness of the services provided. There are several factors in the external environmental that influence the eye care services - such as the availability of trained manpower, supply of eye care consumables, government rules and regulations. There are several instances where successful advocacy has helped to create an enabling environment for eye care service delivery. Providing eye care services in developing countries requires the support - either for direct patient care or for support services such as producing trained manpower or for research and dissemination. Such support, in the form of financial or other resources, can be garnered through advocacy.

  17. Human sound-localization behaviour after multiple changes in eye position.

    NARCIS (Netherlands)

    Grootel, T.J. van; Opstal, A.J. van

    2009-01-01

    Orienting the eyes towards a peripheral sound source calls for a transformation of the head-centred sound coordinates into an oculocentric motor command, which requires an estimate of current eye position. Current models of saccadic control explain spatial accuracy by oculocentric transformations

  18. Testing multiple coordination constraints with a novel bimanual visuomotor task.

    Directory of Open Access Journals (Sweden)

    Helene M Sisti

    Full Text Available The acquisition of a new bimanual skill depends on several motor coordination constraints. To date, coordination constraints have often been tested relatively independently of one another, particularly with respect to isofrequency and multifrequency rhythms. Here, we used a new paradigm to test the interaction of multiple coordination constraints. Coordination constraints that were tested included temporal complexity, directionality, muscle grouping, and hand dominance. Twenty-two healthy young adults performed a bimanual dial rotation task that required left and right hand coordination to track a moving target on a computer monitor. Two groups were compared, either with or without four days of practice with augmented visual feedback. Four directional patterns were tested such that both hands moved either rightward (clockwise, leftward (counterclockwise, inward or outward relative to each other. Seven frequency ratios (3∶1, 2∶1, 3∶2, 1∶1, 2∶3. 1∶2, 1∶3 between the left and right hand were introduced. As expected, isofrequency patterns (1∶1 were performed more successfully than multifrequency patterns (non 1∶1. In addition, performance was more accurate when participants were required to move faster with the dominant right hand (1∶3, 1∶2 and 2∶3 than with the non-dominant left hand (3∶1, 2∶1, 3∶2. Interestingly, performance deteriorated as the relative angular velocity between the two hands increased, regardless of whether the required frequency ratio was an integer or non-integer. This contrasted with previous finger tapping research where the integer ratios generally led to less error than the non-integer ratios. We suggest that this is due to the different movement topologies that are required of each paradigm. Overall, we found that this visuomotor task was useful for testing the interaction of multiple coordination constraints as well as the release from these constraints with practice in the presence of

  19. Cold hands, warm feet: sleep deprivation disrupts thermoregulation and its association with vigilance.

    Science.gov (United States)

    Romeijn, Nico; Verweij, Ilse M; Koeleman, Anne; Mooij, Anne; Steimke, Rosa; Virkkala, Jussi; van der Werf, Ysbrand; Van Someren, Eus J W

    2012-12-01

    Vigilance is affected by induced and spontaneous skin temperature fluctuations. Whereas sleep deprivation strongly affects vigilance, no previous study examined in detail its effect on human skin temperature fluctuations and their association with vigilance. In a repeated-measures constant routine design, skin temperatures were assessed continuously from 14 locations while performance was assessed using a reaction time task, including eyes-open video monitoring, performed five times a day for 2 days, after a normal sleep or sleep deprivation night. Participants were seated in a dimly lit, temperature-controlled laboratory. Eight healthy young adults (five males, age 22.0 ± 1.8 yr (mean ± standard deviation)). One night of sleep deprivation. Mixed-effect regression models were used to evaluate the effect of sleep deprivation on skin temperature gradients of the upper (ear-mastoid), middle (hand-arm), and lower (foot-leg) body, and on the association between fluctuations in performance and in temperature gradients. Sleep deprivation induced a marked dissociation of thermoregulatory skin temperature gradients, indicative of attenuated heat loss from the hands co-occurring with enhanced heat loss from the feet. Sleep deprivation moreover attenuated the association between fluctuations in performance and temperature gradients; the association was best preserved for the upper body gradient. Sleep deprivation disrupts coordination of fluctuations in thermoregulatory skin temperature gradients. The dissociation of middle and lower body temperature gradients may therefore be evaluated as a marker for sleep debt, and the upper body gradient as a possible aid in vigilance assessment when sleep debt is unknown. Importantly, our findings suggest that sleep deprivation affects the coordination between skin blood flow fluctuations and the baroreceptor-mediated cardiovascular regulation that prevents venous pooling of blood in the lower limbs when there is the orthostatic

  20. Aquaporins in the Eye

    DEFF Research Database (Denmark)

    Tran, Thuy Linh; Hamann, Steffen; Heegaard, Steffen

    2017-01-01

    The major part of the eye consists of water . Continuous movement of water and ions between the ocular compartments and to the systemic circulation is pivotal for many physiological functions in the eye. The movement of water facilitates removal of the many metabolic products of corneal-, ciliary...... pressure. In the retina, water is transported into the vitreous body and across the retinal pigment epithelium to regulate the extracellular environment and the hydration of the retina. Aquaporins (AQPs ) take part in the water transport throughout the eye....

  1. Eye Movements Reveal How Task Difficulty Moulds Visual Search

    Science.gov (United States)

    Young, Angela H.; Hulleman, Johan

    2013-01-01

    In two experiments we investigated the relationship between eye movements and performance in visual search tasks of varying difficulty. Experiment 1 provided evidence that a single process is used for search among static and moving items. Moreover, we estimated the functional visual field (FVF) from the gaze coordinates and found that its size…

  2. Binocular eye movements in health and disease

    Science.gov (United States)

    Tyler, Christopher W.

    2013-03-01

    Binocular eye movements form a finely-tuned system that requires accurate coordination of the oculomotor dynamics and supports the vergence movements for tracking the fine binocular disparities required for 3D vision, and are particularly susceptible to disruption by brain injury and other neural dysfunctions. Saccadic dynamics for a population of 84 diverse participants show tight coefficients of variation of 2-10% of the mean value of each parameter. Significantly slower dynamics were seen for vertical upward saccades. Binocular coordination of saccades was accurate to within 1-4%, implying the operation of brainstem coordination mechanisms rather than independent cortical control of the two eyes. A new principle of oculomotor control - reciprocal binocular inhibition - is introduced to complement Sherrington's and Hering's Laws. This new law accounts for the fact that symmetrical vergence responses are about five times slower than saccades of the same amplitude, although a comprehensive analysis of asymmetrical vergence responses revealed unexpected variety in vergence dynamics. This analysis of the variety of human vergence responses thus contributes substantially to the understanding of the oculomotor control mechanisms underlying the generation of vergence movements and of the deficits in the oculomotor control resulting from mild traumatic brain injury.

  3. Defective Hand1 phosphoregulation uncovers essential roles for Hand1 in limb morphogenesis.

    Science.gov (United States)

    Firulli, Beth A; Milliar, Hannah; Toolan, Kevin P; Harkin, Jade; Fuchs, Robyn K; Robling, Alex G; Firulli, Anthony B

    2017-07-01

    The morphogenesis of the vertebrate limbs is a complex process in which cell signaling and transcriptional regulation coordinate diverse structural adaptations in diverse species. In this study, we examine the consequences of altering Hand1 dimer choice regulation within developing vertebrate limbs. Although Hand1 deletion via the limb-specific Prrx1-Cre reveals a non-essential role for Hand1 in mouse limb morphogenesis, altering Hand1 phosphoregulation, and consequently Hand1 dimerization affinities, results in a severe truncation of proximal-anterior limb elements. Molecular analysis reveals a non-cell-autonomous mechanism that causes widespread cell death within the embryonic limb bud. In addition, we observe changes in proximal-anterior gene regulation, including a reduction in the expression of Irx3, Irx5, Gli3 and Alx4, all of which are upregulated in Hand2 limb conditional knockouts. A reduction of Hand2 and Shh gene dosage improves the integrity of anterior limb structures, validating the importance of the Twist-family bHLH dimer pool in limb morphogenesis. © 2017. Published by The Company of Biologists Ltd.

  4. Hands of early primates.

    Science.gov (United States)

    Boyer, Doug M; Yapuncich, Gabriel S; Chester, Stephen G B; Bloch, Jonathan I; Godinot, Marc

    2013-12-01

    Questions surrounding the origin and early evolution of primates continue to be the subject of debate. Though anatomy of the skull and inferred dietary shifts are often the focus, detailed studies of postcrania and inferred locomotor capabilities can also provide crucial data that advance understanding of transitions in early primate evolution. In particular, the hand skeleton includes characteristics thought to reflect foraging, locomotion, and posture. Here we review what is known about the early evolution of primate hands from a comparative perspective that incorporates data from the fossil record. Additionally, we provide new comparative data and documentation of skeletal morphology for Paleogene plesiadapiforms, notharctines, cercamoniines, adapines, and omomyiforms. Finally, we discuss implications of these data for understanding locomotor transitions during the origin and early evolutionary history of primates. Known plesiadapiform species cannot be differentiated from extant primates based on either intrinsic hand proportions or hand-to-body size proportions. Nonetheless, the presence of claws and a different metacarpophalangeal [corrected] joint form in plesiadapiforms indicate different grasping mechanics. Notharctines and cercamoniines have intrinsic hand proportions with extremely elongated proximal phalanges and digit rays relative to metacarpals, resembling tarsiers and galagos. But their hand-to-body size proportions are typical of many extant primates (unlike those of tarsiers, and possibly Teilhardina, which have extremely large hands). Non-adapine adapiforms and omomyids exhibit additional carpal features suggesting more limited dorsiflexion, greater ulnar deviation, and a more habitually divergent pollex than observed plesiadapiforms. Together, features differentiating adapiforms and omomyiforms from plesiadapiforms indicate increased reliance on vertical prehensile-clinging and grasp-leaping, possibly in combination with predatory behaviors in

  5. Transcriptome analysis of Nautilus and pygmy squid developing eye provides insights in lens and eye evolution.

    Directory of Open Access Journals (Sweden)

    Konstantinos Sousounis

    Full Text Available Coleoid cephalopods like squids have a camera-type eye similar to vertebrates. On the other hand, Nautilus (Nautiloids has a pinhole eye that lacks lens and cornea. Since pygmy squid and Nautilus are closely related species they are excellent model organisms to study eye evolution. Having being able to collect Nautilus embryos, we employed next-generation RNA sequencing using Nautilus and pygmy squid developing eyes. Their transcriptomes were compared and analyzed. Enrichment analysis of Gene Ontology revealed that contigs related to nucleic acid binding were largely up-regulated in squid, while the ones related to metabolic processes and extracellular matrix-related genes were up-regulated in Nautilus. These differences are most likely correlated with the complexity of tissue organization in these species. Moreover, when the analysis focused on the eye-related contigs several interesting patterns emerged. First, contigs from both species related to eye tissue differentiation and morphogenesis as well as to cilia showed best hits with their Human counterparts, while contigs related to rabdomeric photoreceptors showed the best hit with their Drosophila counterparts. This bolsters the idea that eye morphogenesis genes have been generally conserved in evolution, and compliments other studies showing that genes involved in photoreceptor differentiation clearly follow the diversification of invertebrate (rabdomeric and vertebrate (ciliated photoreceptors. Interestingly some contigs showed as good a hit with Drosophila and Human homologues in Nautilus and squid samples. One of them, capt/CAP1, is known to be preferentially expressed in Drosophila developing eye and in vertebrate lens. Importantly our analysis also provided evidence of gene duplication and diversification of their function in both species. One of these genes is the Neurofibromatosis 1 (NF1/Nf1, which in mice has been implicated in lens formation, suggesting a hitherto unsuspected role

  6. Transcriptome analysis of Nautilus and pygmy squid developing eye provides insights in lens and eye evolution.

    Science.gov (United States)

    Sousounis, Konstantinos; Ogura, Atsushi; Tsonis, Panagiotis A

    2013-01-01

    Coleoid cephalopods like squids have a camera-type eye similar to vertebrates. On the other hand, Nautilus (Nautiloids) has a pinhole eye that lacks lens and cornea. Since pygmy squid and Nautilus are closely related species they are excellent model organisms to study eye evolution. Having being able to collect Nautilus embryos, we employed next-generation RNA sequencing using Nautilus and pygmy squid developing eyes. Their transcriptomes were compared and analyzed. Enrichment analysis of Gene Ontology revealed that contigs related to nucleic acid binding were largely up-regulated in squid, while the ones related to metabolic processes and extracellular matrix-related genes were up-regulated in Nautilus. These differences are most likely correlated with the complexity of tissue organization in these species. Moreover, when the analysis focused on the eye-related contigs several interesting patterns emerged. First, contigs from both species related to eye tissue differentiation and morphogenesis as well as to cilia showed best hits with their Human counterparts, while contigs related to rabdomeric photoreceptors showed the best hit with their Drosophila counterparts. This bolsters the idea that eye morphogenesis genes have been generally conserved in evolution, and compliments other studies showing that genes involved in photoreceptor differentiation clearly follow the diversification of invertebrate (rabdomeric) and vertebrate (ciliated) photoreceptors. Interestingly some contigs showed as good a hit with Drosophila and Human homologues in Nautilus and squid samples. One of them, capt/CAP1, is known to be preferentially expressed in Drosophila developing eye and in vertebrate lens. Importantly our analysis also provided evidence of gene duplication and diversification of their function in both species. One of these genes is the Neurofibromatosis 1 (NF1/Nf1), which in mice has been implicated in lens formation, suggesting a hitherto unsuspected role in the evolution

  7. Hand Hygiene: When and How

    Science.gov (United States)

    Hand Hygiene When and How August 2009 How to handrub? How to handwash? RUB HANDS FOR HAND HYGIENE! WASH HANDS WHEN VISIBLY SOILED Duration of the ... from its use. When? YOUR 5 MOMENTS FOR HAND HYGIENE 1 BEFORETOUCHINGA PATIENT 2 B P ECFLOER R ...

  8. What Is Dry Eye?

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    Full Text Available ... Guide Find an Ophthalmologist Advanced Search Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About ...

  9. Eye Injuries (For Parents)

    Science.gov (United States)

    ... of your child's routine activities, such as a sport , follow up by investing in an ounce of prevention — protective goggles or unbreakable glasses ... Your Child's Medical History First Aid: Eye Injuries Your Child's Vision What ...

  10. What Is Dry Eye?

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    Full Text Available ... Dry Eye Symptoms Related Ask an Ophthalmologist Answers Can a six-month dissolvable punctal plug be removed ... insert a permanent punctal plug? Sep 12, 2017 Can you explain why I have halos and blurry ...

  11. What Is Dry Eye?

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    Full Text Available ... Advanced Search Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member Services Advocacy Foundation About Subspecialties & More Academy Publications ...

  12. Applied eye tracking research

    NARCIS (Netherlands)

    Jarodzka, Halszka

    2011-01-01

    Jarodzka, H. (2010, 12 November). Applied eye tracking research. Presentation and Labtour for Vereniging Gewone Leden in oprichting (VGL i.o.), Heerlen, The Netherlands: Open University of the Netherlands.

  13. Multimodal eye recognition

    Science.gov (United States)

    Zhou, Zhi; Du, Yingzi; Thomas, N. L.; Delp, Edward J., III

    2010-04-01

    Multimodal biometrics use more than one means of biometric identification to achieve higher recognition accuracy, since sometimes a unimodal biometric is not good enough used to do identification and classification. In this paper, we proposed a multimodal eye recognition system, which can obtain both iris and sclera patterns from one color eye image. Gabor filter and 1-D Log-Gabor filter algorithms have been applied as the iris recognition algorithms. In sclera recognition, we introduced automatic sclera segmentation, sclera pattern enhancement, sclera pattern template generation, and sclera pattern matching. We applied kernelbased matching score fusion to improve the performance of the eye recognition system. The experimental results show that the proposed eye recognition method can achieve better performance compared to unimodal biometric identification, and the accuracy of our proposed kernel-based matching score fusion method is higher than two classic linear matching score fusion methods: Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA).

  14. What Is Dry Eye?

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    Full Text Available ... Dry Eye Symptoms Related Ask an Ophthalmologist Answers Can a six-month dissolvable punctal plug be removed ... insert a permanent punctal plug? Sep 12, 2017 Can lupus affect my vision? May 27, 2017 Is ...

  15. What Is Dry Eye?

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    Full Text Available ... plug? Sep 12, 2017 Can you explain why I have halos and blurry vision in the morning? ... 06, 2017 Why are my eyes bloodshot when I wake up? Jun 26, 2016 Find an Ophthalmologist ...

  16. About the Eye

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    Full Text Available ... support research, training, health information dissemination, and other programs with respect to blinding eye diseases, visual disorders, ... and Funding Extramural Research Division of Extramural Science Programs Division of Extramural Activities Extramural Contacts NEI Division ...

  17. What Is Dry Eye?

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    Full Text Available ... for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses Senior Ophthalmologists Young Ophthalmologists Tools and Services Emergency Relief EyeCare America Help IRIS Registry Medicare ...

  18. About the Eye

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    Full Text Available ... Extramural Science Programs Division of Extramural Activities Extramural ... is the small, sensitive area of the retina needed for central vision. It contains the fovea. Lens is the clear part of the eye behind ...

  19. About the Eye

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    Full Text Available ... are made up of many different parts that work together to help you see. Check out the ... Learn how the different parts of your eye work together so you can see and make sense ...

  20. About the Eye

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  1. About the Eye

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    Full Text Available ... to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and requirements of ... Pressroom Contacts Dustin Hays - Chief, Science Communication dustin.hays@nih.gov Anna Harper - Media Relations ...

  2. About the Eye

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    Full Text Available ... part of your eye and what it does. Macula (MACK-yoo-luh) is the small, sensitive area ... FOH-vee-uh) is the center of the macula, where your vision is sharpest. Optic nerve (OP- ...

  3. About the Eye

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    Full Text Available ... Accomplishments Budget and Congress About the NEI Director History of the NEI NEI 50th Anniversary NEI Women ... Emily Y. Chew, M.D., Deputy Clinical Director Education Programs National Eye Health Education Program (NEHEP) Diabetic ...

  4. What Is Dry Eye?

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    Full Text Available ... eyes don’t make enough tears or something affects one or more layers of the tear film. ... in the morning? Jun 12, 2017 Can lupus affect my vision? May 27, 2017 Is stopping Restasis ...

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  7. About the Eye

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    Full Text Available ... about each part of your eye and what it does. Macula (MACK-yoo-luh) is the small, ... area of the retina needed for central vision. It contains the fovea. Lens is the clear part ...

  8. About the Eye

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    Full Text Available ... to blinding eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and requirements of the blind.” ... Health Information Frequently asked questions ...

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    Full Text Available ... to the NEI Contact Us Visiting the NIH Campus Mission Statement As part of the federal government’s ... Emily Y. Chew, M.D., Deputy Clinical Director Education Programs National Eye Health Education Program (NEHEP) Diabetic ...

  10. What Is Dry Eye?

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    Full Text Available ... information about eye health and preserving your vision. Privacy Policy Related Please Don’t Shave the Inside ... the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media ...

  11. Eye Complications in IBD

    Science.gov (United States)

    ... necessary. Another possible consequence may be night blindness. Artificial tears provide relief of symptoms. Vitamin A supplements, ... of the lens of the eye that impairs vision). SUMMARY Although not everyone with Crohn’s disease or ...

  12. About the Eye

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    Full Text Available ... is to “conduct and support research, training, health information dissemination, and other programs with respect to blinding eye ... Media Policies and Other Important Links NEI Employee Emergency Information NEI Intranet (Employees Only) *PDF files require ...

  13. What Is Dry Eye?

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    Full Text Available ... Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American Academy of Ophthalmology 2017 Our Sites EyeWiki International Society of Refractive Surgery * Required * First Name: * Last Name: ...

  14. What Is Dry Eye?

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    Full Text Available ... the Inside of Your Eyelid Nov 29, 2017 New Dry Eye Treatment is a Tear-Jerker Jul ... Privacy Policy Terms of Service For Advertisers For Media Ophthalmology Job Center © American Academy of Ophthalmology 2017 ...

  15. About the Eye

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    Full Text Available ... NEI Women Scientists Advisory Committee (WSAC) Board of Scientific Counselors National Advisory Eye Council (NAEC) Donating to ... for the media Pressroom Contacts Dustin Hays - Chief, Science Communication dustin.hays@nih.gov Anna Harper - Media ...

  16. Using Eye Makeup

    Science.gov (United States)

    ... in a moving vehicle. Do not separate your mascara-clumped lashes with sharp items. If you tend ... all eye makeup at night before sleeping, especially mascara that can stick to the lashes. Brush a ...

  17. Standard eye exam

    Science.gov (United States)

    ... the eye ( glaucoma ) using a method called tonometry Color blindness is tested using cards with colored dots that ... Astigmatism (abnormally curved cornea) Blocked tear duct Cataracts Color blindness Corneal abrasion (or dystrophy) Corneal ulcers and infections ...

  18. Sports and Your Eyes

    Science.gov (United States)

    ... at high risk for eye injuries. Baseball Basketball Water Sports Boxing ... Protective Eyewear Fast Facts Everyone should wear protective eyewear. Ordinary prescription glasses, contact lenses, and sunglasses won’t protect you from injuries. ...

  19. About the Eye

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    Full Text Available ... Search Search the NEI Website search NEI on Social Media | Search A-Z | en español | Text size S M L ... Board of Scientific Counselors National Advisory Eye Council (NAEC) Donating to ...

  20. Diabetic Eye Problems

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    ... damage your eyes. The most common problem is diabetic retinopathy. It is a leading cause of blindness ... You need a healthy retina to see clearly. Diabetic retinopathy damages the tiny blood vessels inside your ...

  1. What Is Dry Eye?

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    Full Text Available ... of tears or tear film. How do tears work? When you blink, a film of tears spreads ... Care, Part 5 Mar 19, 2013 Eye Makeup Safety Tips Sep 25, 2012 Follow The Academy Professionals: ...

  2. About the Eye

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    Full Text Available ... Disease Education Program Glaucoma Education Program Low Vision Education Program ... a Scientist Video Series Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety ...

  3. About the Eye

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    Full Text Available ... of the NEI NEI 50th Anniversary NEI Women Scientists Advisory Committee (WSAC) Board of Scientific Counselors National ... All About Vision About the Eye Ask a Scientist Video Series Glossary The Visual System Your Eyes’ ...

  4. Get Your Eyes Tested

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    ... blurry or distorted at all distances Presbyopia (“prez-bee-OH-pee-uh”) – a condition that older adults ... sections Take Action! Take Action: Schedule Your Exam Protect your vision. Get regular eye exams so you ...

  5. What Is Dry Eye?

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  6. Eye Injuries at Work

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    ... work. Use machine guarding, work screens or other engineering controls. Use proper eye protection. Wear protective eyewear ... Us About the Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms ...

  7. Lasik eye surgery - slideshow

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    ... presentations/100206.htm Lasik eye surgery - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  8. What Is Dry Eye?

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    Full Text Available ... Kierstan Boyd Reviewed By: Brenda Pagan-Duran MD Sep. 01, 2017 Our eyes need tears to stay ... tear duct to insert a permanent punctal plug? Sep 12, 2017 Can lupus affect my vision? May ...

  9. What Is Dry Eye?

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    Full Text Available ... of what we see as tears. This layer cleans the eye, washing away particles that do not ... Last Name: Member ID: * Phone Number: * Email: * Enter code: * Message: Thank you Your feedback has been sent.

  10. Eye Disease and Development

    DEFF Research Database (Denmark)

    Andersen, Thomas Barnebeck; Dalgaard, Carl-Johan Lars; Selaya, Pablo

    This research advances the hypothesis that cross-country variation in the historical incidence of eye disease has influenced the current global distribution of per capita income. The theory is that pervasive eye disease diminished the incentive to accumulate skills, thereby delaying the fertility...... transition and the take-off to sustained economic growth. In order to estimate the influence from eye disease incidence empirically, we draw on an important fact from the field of epidemiology: Exposure to solar ultraviolet B radiation (UVB-R) is an underlying determinant of several forms of eye disease...... are robust to the inclusion of an extensive set of climate and geography controls. Moreover, using a global data set on economic activity for all terrestrial grid cells we show that the link between UVB-R and economic development survives the inclusion of country fixed effect....

  11. Diagram of the Eye

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    ... eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and ... Clinical Studies Publications Catalog Photos and Images Spanish Language Information Grants and Funding Extramural Research Division of ...

  12. About the Eye

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  13. The Aging Eye

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    ... eye diseases, visual disorders, mechanisms of visual function, preservation of sight, and the special health problems and ... Clinical Studies Publications Catalog Photos and Images Spanish Language Information Grants and Funding Extramural Research Division of ...

  14. About the Eye

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    Full Text Available ... of visual function, preservation of sight, and the special health problems and requirements of the blind.” News & ... Emily Y. Chew, M.D., Deputy Clinical Director Education Programs National Eye Health Education Program (NEHEP) Diabetic ...

  15. About the Eye

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    Full Text Available ... luh) is the small, sensitive area of the retina needed for central vision. It contains the fovea. ... iris that helps to focus light on the retina. It allows the eye to focus on both ...

  16. About the Eye

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  17. What Is Dry Eye?

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  18. About the Eye

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    Full Text Available ... tic nurv) is the bundle of more than 1 million nerve fibers that carry visual messages from the ... now! Learn how the different parts of your eye work together so you can see and make sense ...

  19. Anatomy of the Eye

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    ... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Anatomy of the Eye En Español Read in Chinese External (Extraocular) Anatomy Extraocular Muscles: There are six muscles that are ...

  20. What Is Dry Eye?

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