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Sample records for hand eye coordination

  1. Coordinated Flexibility: How Initial Gaze Position Modulates Eye-Hand Coordination and Reaching

    ERIC Educational Resources Information Center

    Adam, Jos J.; Buetti, Simona; Kerzel, Dirk

    2012-01-01

    Reaching to targets in space requires the coordination of eye and hand movements. In two experiments, we recorded eye and hand kinematics to examine the role of gaze position at target onset on eye-hand coordination and reaching performance. Experiment 1 showed that with eyes and hand aligned on the same peripheral start location, time lags…

  2. Eye Hand Coordination in Children with Cerebral Palsy

    PubMed Central

    Saavedra, Sandra; Joshi, Aditi; Woollacott, Marjorie; van Donkelaar, Paul

    2009-01-01

    Reaching to grasp an object of interest requires complex sensorimotor coordination involving eye, head, hand and trunk. While numerous studies have demonstrated deficits in each of these systems individually, little is known about how children with cerebral palsy (CP) coordinate multiple motor systems for functional tasks. Here we used kinematics, remote eye tracking and a trunk support device to examine the functional coupling of the eye, head and hand and the extent to which it was constrained by trunk postural control in 10 children with CP (6–16 years). Eye movements in children with CP were similar to typically developing (TD) peers, while hand movements were significantly slower. Postural support influenced initiation of hand movements in the youngest children (TD & CP) and execution of hand movements in children with CP differentially depending on diagnosis. Across all diagnostic categories, the most robust distinction between TD children and children with CP was in their ability to isolate eye, head and hand movements. Results of this study suggest that deficits in motor coordination for accurate reaching in children with CP may reflect coupled eye, head, and hand movements. We have previously suggested that coupled activation of effectors may be the default output for the CNS during early development. PMID:18830589

  3. Hand-eye coordination with an active camera head

    NASA Astrophysics Data System (ADS)

    Bishay, Magued; Peters, R. Alan; Wilkes, Don M.; Kawamura, Kazuhiko

    1997-09-01

    Hand-eye coordination is the coupling between vision and manipulation. Visual servoing is the term applied to hand-eye coordination in robots. In recent years, research has demonstrated that active vision -- active control of camera position and camera parameters -- facilitates a robot's interaction with the world. One aspect of active vision is centering an object in an image. This is known as gaze stabilization or fixation. This paper presents a new algorithm that applies target fixation to image-based visual servoing. This algorithm, called fixation point servoing (FPS), uses target fixation to eliminate the need for Jacobian computation Additionally, FPS reburies only the rotation relationship between the camera head and the gripper frames and does not require accurate tracking of the gripper. FPS was tested on a robotics system called ISAC and experimental results are shown. FPS was also compared to a classical Jacobian-based technique using simulations of both algorithms.

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

    PubMed

    Huette, Stephanie; Kello, Christopher T; Rhodes, Theo; 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

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

    PubMed Central

    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. Coordinated flexibility: how initial gaze position modulates eye-hand coordination and reaching.

    PubMed

    Adam, Jos J; Buetti, Simona; Kerzel, Dirk

    2012-08-01

    Reaching to targets in space requires the coordination of eye and hand movements. In two experiments, we recorded eye and hand kinematics to examine the role of gaze position at target onset on eye-hand coordination and reaching performance. Experiment 1 showed that with eyes and hand aligned on the same peripheral start location, time lags between eye and hand onsets were small and initiation times were substantially correlated, suggesting simultaneous control and tight eye-hand coupling. With eyes and hand departing from different start locations (gaze aligned with the center of the range of possible target positions), time lags between eye and hand onsets were large and initiation times were largely uncorrelated, suggesting independent control and decoupling of eye and hand movements. Furthermore, initial gaze position strongly mediated manual reaching performance indexed by increments in movement time as a function of target distance. Experiment 2 confirmed the impact of target foveation in modulating the effect of target distance on movement time. Our findings reveal the operation of an overarching, flexible neural control system that tunes the operation and cooperation of saccadic and manual control systems depending on where the eyes look at target onset. PMID:22390297

  7. Acquisition of Eye-hand Coordination Skills for Videoendoscopic Surgery

    PubMed

    Tsai; Heinrichs

    1994-08-01

    Evaluation of eye-hand coordination skills in relation to experiential human factors may lead to improved instruction for videoendoscopic surgical skills acquisition. Twenty-nine subjects (medical students or residents in surgical specialties) volunteered to perform three exercises of increasing complexity in an "inanimate" trainer system that simulated the eye-hand coordination tasks inherent in a laboratory videoendoscopic surgical environment. Fourteen subjects participated in a biweekly practice program of 4 weeks duration using an inanimate trainer. Fifteen subjects had no practice on the laparoscopic trainer during the 4 weeks. Both groups were tested after demonstration on three exercises at the beginning and end of a 4 week period and all performed the procedures in solitude. Both groups of subjects increased performance levels (time and accuracy) over the four weeks, but improvement was significantly greater for the practicing subjects. After eight sessions, convergence of performance levels was observed, but plateauing of performance levels was not evident, even with the simple paradigms evaluated. To investigate what factors contribute to learning, subjects were assessed with respect to their surgical experiences, personality, and self-evaluated motor skills. Subjects with prior endoscopic surgical experience, interest in mechanical activities (as measured by the Strong Interest Inventory), or regular engagement in video game play tended to be more skillful initially, but demonstrated less improvement in performance levels after practice than subjects who had lower levels of experience, interest, or video game play. Manual dexterity (as measured by the Purdue Pegboard Manual Dexterity Test) was positively related to the degree of observed improvement. We conclude that "inanimate" videoendoscopic paradigms offer relatively inexpensive and useful training exercises for acquiring basic eye-hand coordination skills. Relevance for animate laboratory skills

  8. RECOGNIZING BEHAVIOR IN HAND-EYE COORDINATION PATTERNS.

    PubMed

    Yi, Weilie; Ballard, Dana

    2009-01-01

    Modeling human behavior is important for the design of robots as well as human-computer interfaces that use humanoid avatars. Constructive models have been built, but they have not captured all of the detailed structure of human behavior such as the moment-to-moment deployment and coordination of hand, head and eye gaze used in complex tasks. We show how this data from human subjects performing a task can be used to program a dynamic Bayes network (DBN) which in turn can be used to recognize new performance instances. As a specific demonstration we show that the steps in a complex activity such as sandwich making can be recognized by a DBN in real time. PMID:20862267

  9. RECOGNIZING BEHAVIOR IN HAND-EYE COORDINATION PATTERNS

    PubMed Central

    Yi, Weilie; Ballard, Dana

    2010-01-01

    Modeling human behavior is important for the design of robots as well as human-computer interfaces that use humanoid avatars. Constructive models have been built, but they have not captured all of the detailed structure of human behavior such as the moment-to-moment deployment and coordination of hand, head and eye gaze used in complex tasks. We show how this data from human subjects performing a task can be used to program a dynamic Bayes network (DBN) which in turn can be used to recognize new performance instances. As a specific demonstration we show that the steps in a complex activity such as sandwich making can be recognized by a DBN in real time. PMID:20862267

  10. Hand/Eye Coordination For Fine Robotic Motion

    NASA Technical Reports Server (NTRS)

    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.

  11. Effect of Participation in a Cup Stacking Unit on Hand-Eye Coordination of Elementary Children

    ERIC Educational Resources Information Center

    Hart, Melanie A.; Smith, Lori A.; DeChant-Bruennig, Ann

    2006-01-01

    The purpose of this study was to empirically examine the influence of a cup stacking instructional unit on the hand-eye coordination of children. Participants (N = 104) consisted of three grade level groups (first/second, third and fourth). Within each grade level participants were randomly assigned to either an experimental or a control group.…

  12. The optic chiasm: a turning point in the evolution of eye/hand coordination

    PubMed Central

    2013-01-01

    The primate visual system has a uniquely high proportion of ipsilateral retinal projections, retinal ganglial cells that do not cross the midline in the optic chiasm. The general assumption is that this developed due to the selective advantage of accurate depth perception through stereopsis. Here, the hypothesis that the need for accurate eye-forelimb coordination substantially influenced the evolution of the primate visual system is presented. Evolutionary processes may change the direction of retinal ganglial cells. Crossing, or non-crossing, in the optic chiasm determines which hemisphere receives visual feedback in reaching tasks. Each hemisphere receives little tactile and proprioceptive information about the ipsilateral hand. The eye-forelimb hypothesis proposes that abundant ipsilateral retinal projections developed in the primate brain to synthesize, in a single hemisphere, visual, tactile, proprioceptive, and motor information about a given hand, and that this improved eye-hand coordination and optimized the size of the brain. If accurate eye-hand coordination was a major factor in the evolution of stereopsis, stereopsis is likely to be highly developed for activity in the area where the hands most often operate. The primate visual system is ideally suited for tasks within arm’s length and in the inferior visual field, where most manual activity takes place. Altering of ocular dominance in reaching tasks, reduced cross-modal cuing effects when arms are crossed, response of neurons in the primary motor cortex to viewed actions of a hand, multimodal neuron response to tactile as well as visual events, and extensive use of multimodal sensory information in reaching maneuvers support the premise that benefits of accurate limb control influenced the evolution of the primate visual system. The eye-forelimb hypothesis implies that evolutionary change toward hemidecussation in the optic chiasm provided parsimonious neural pathways in animals developing frontal

  13. Influence of cup stacking on hand-eye coordination and reaction time of second-grade students.

    PubMed

    Udermann, Brian E; Murray, Steven R; Mayer, John M; Sagendorf, Kenneth

    2004-04-01

    Cup stacking has been adopted recently by many physical education programs to enhance rudimentary motor skills such as hand-eye coordination and ambidexterity as well as quickness and concentration; however, no empirical evidence has been published to support these claims. We examined the influence of cup stacking on hand-eye coordination and reaction time of 24 boys and 18 girls in second grade as measured by the Soda Pop and Yardstick tests, respectively. Two physical education classes were randomly assigned as treatment and control groups and were pre- and posttested for hand-eye coordination and reaction time. The treatment group participated in a 5-wk. cup-stacking program. Significant improvements were noted for both hand-eye coordination and reaction time between the pre- and posttest scores for this group but not for the control group. Therefore, cup stacking is indeed effective in enhancing hand-eye coordination and reaction time. PMID:15141904

  14. Eye-hand coordination in children with high functioning autism and Asperger's disorder using a gap-overlap paradigm.

    PubMed

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

    2013-04-01

    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 fixation latencies in absence of manual response. ASD patients showed less efficient eye-hand coordination, which was particularly evident when pointing towards a target was being fixated. The data of normally developing participants confirmed that manual gap effects are more likely for more complex hand movements. An important discrepancy was discovered in participants with ASD: beside normal eye gap effects, they showed no concurrent hand gap effects when pointing to targets. This result has been interpreted as a further sign of inefficient eye-hand coordination in this patient population. PMID:22865152

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

    ERIC Educational Resources Information Center

    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…

  16. A common control signal and a ballistic stage can explain the control of coordinated eye-hand movements.

    PubMed

    Gopal, Atul; Murthy, Aditya

    2016-06-01

    Voluntary control has been extensively studied in the context of eye and hand movements made in isolation, yet little is known about the nature of control during eye-hand coordination. We probed this with a redirect task. Here subjects had to make reaching/pointing movements accompanied by coordinated eye movements but had to change their plans when the target occasionally changed its position during some trials. Using a race model framework, we found that separate effector-specific mechanisms may be recruited to control eye and hand movements when executed in isolation but when the same effectors are coordinated a unitary mechanism to control coordinated eye-hand movements is employed. Specifically, we found that performance curves were distinct for the eye and hand when these movements were executed in isolation but were comparable when they were executed together. Second, the time to switch motor plans, called the target step reaction time, was different in the eye-alone and hand-alone conditions but was similar in the coordinated condition under assumption of a ballistic stage of ∼40 ms, on average. Interestingly, the existence of this ballistic stage could predict the extent of eye-hand dissociations seen in individual subjects. Finally, when subjects were explicitly instructed to control specifically a single effector (eye or hand), redirecting one effector had a strong effect on the performance of the other effector. Taken together, these results suggest that a common control signal and a ballistic stage are recruited when coordinated eye-hand movement plans require alteration. PMID:26888104

  17. Learning robotic eye-arm-hand coordination from human demonstration: a coupled dynamical systems approach.

    PubMed

    Lukic, Luka; Santos-Victor, José; Billard, Aude

    2014-04-01

    We investigate the role of obstacle avoidance in visually guided reaching and grasping movements. We report on a human study in which subjects performed prehensile motion with obstacle avoidance where the position of the obstacle was systematically varied across trials. These experiments suggest that reaching with obstacle avoidance is organized in a sequential manner, where the obstacle acts as an intermediary target. Furthermore, we demonstrate that the notion of workspace travelled by the hand is embedded explicitly in a forward planning scheme, which is actively involved in detecting obstacles on the way when performing reaching. We find that the gaze proactively coordinates the pattern of eye-arm motion during obstacle avoidance. This study provides also a quantitative assessment of the coupling between the eye-arm-hand motion. We show that the coupling follows regular phase dependencies and is unaltered during obstacle avoidance. These observations provide a basis for the design of a computational model. Our controller extends the coupled dynamical systems framework and provides fast and synchronous control of the eyes, the arm and the hand within a single and compact framework, mimicking similar control system found in humans. We validate our model for visuomotor control of a humanoid robot. PMID:24570352

  18. Vision and "Hand-Eye" Coordination for the Fujitsu HOAP-2 Humanoid Robot

    NASA Technical Reports Server (NTRS)

    Moore, Jeffrey D.

    2005-01-01

    Software was developed for a Fujitsu HOAP-2 humanoid robot to demonstrate that such "human form" robots can be used to perform useful tasks in an unknown environment; specifically, that they can operate with or in the place of humans to carry out construction operations necessary for space exploration, such as building or maintaining planetary surface habitats for humans. This paper describes the autonomous vision and hand-eye coordination software that enables the HOAP-2 to locate and manipulate objects. Simple vision and pattern detection algorithms including color filtering, noise filtering, image segmentation, orientation filters, and a feedback controlled tracking system enable the robot to locate marked building materials in the workspace. Experimentally determined spatial mappings associate locations in the visual field with the arm joint angles and trajectories necessary to reach these locations, allowing the robot to reach for and manipulate the building materials. These capabilities, when combined with locomotion capabilities, enable the robot to operate autonomously in an unknown workspace.

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

    NASA Astrophysics Data System (ADS)

    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.

  20. Coordination of hand shape.

    PubMed

    Pesyna, Colin; Pundi, Krishna; Flanders, Martha

    2011-03-01

    The neural control of hand movement involves coordination of the sensory, motor, and memory systems. Recent studies have documented the motor coordinates for hand shape, but less is known about the corresponding patterns of somatosensory activity. To initiate this line of investigation, the present study characterized the sense of hand shape by evaluating the influence of differences in the amount of grasping or twisting force, and differences in forearm orientation. Human subjects were asked to use the left hand to report the perceived shape of the right hand. In the first experiment, six commonly grasped items were arranged on the table in front of the subject: bottle, doorknob, egg, notebook, carton, and pan. With eyes closed, subjects used the right hand to lightly touch, forcefully support, or imagine holding each object, while 15 joint angles were measured in each hand with a pair of wired gloves. The forces introduced by supporting or twisting did not influence the perceptual report of hand shape, but for most objects, the report was distorted in a consistent manner by differences in forearm orientation. Subjects appeared to adjust the intrinsic joint angles of the left hand, as well as the left wrist posture, so as to maintain the imagined object in its proper spatial orientation. In a second experiment, this result was largely replicated with unfamiliar objects. Thus, somatosensory and motor information appear to be coordinated in an object-based, spatial-coordinate system, sensitive to orientation relative to gravitational forces, but invariant to grasp forcefulness. PMID:21389230

  1. Benefits of early development of eye-hand coordination: evidence from the LOOK longitudinal study.

    PubMed

    Telford, R D; Cunningham, R B; Telford, R M; Olive, L S; Byrne, D G; Abhayaratna, W P

    2013-10-01

    We investigated longitudinal and cross-sectional relationships between eye-hand coordination (EHC) and cardiorespiratory fitness (multistage run), physical activity (pedometers), percent body fat (%BF, dual energy x-ray absorptiometry), body image, and organized sport participation (questionnaires) in 406 boys and 384 girls at 8 and 10 years of age. EHC was measured by a throw and wall-rebound catch test involving 40 attempts of increasing difficulty. Median EHC improved during two years from 18 to 32 (boys) and 9 to 24 (girls), and gender differences and improvements were both significant (P < 0.001). Cross-sectional analyses showed that boys and girls with better EHC were fitter (P < 0.001), and a longitudinal relationship showed that girls who improved their EHC over the two years became fitter (P < 0.001). There was also evidence that children with better EHC possessed a more positive body image (P = 0.05 for combined sex data), but there was no evidence of any relationships between EHC and %BF or PA (both P > 0.3). Finally, even at age 8 years, boys and girls participating in organized sport possessed better EHC than non-participants. These data provide evidence for the premise that early acquisition of this single motor skill promotes the development of a child's fitness, body image, and participation in sport. PMID:23614667

  2. Neuronal activity related to eye-hand coordination in the primate premotor cortex.

    PubMed

    Jouffrais, C; Boussaoud, D

    1999-09-01

    To test the functional implications of gaze signals that we previously reported in the dorsal premotor cortex (PMd), we trained two rhesus monkeys to point to visual targets presented on a touch screen while controlling their gaze orientation. Each monkey had to perform four different tasks. To initiate a trial, the monkey had to put his hand on a starting position at the center of the touch screen and fixate a fixation point. In one task, the animal had to make a reaching movement to a peripheral target randomly presented at one of eight possible locations on a circle while maintaining fixation at the center of this virtual circle (central fixation + reaching). In the second task, the monkey maintained fixation at the location of the upcoming peripheral target and, later, reached to that location. After a delay, the target was turned on and the monkey made a reaching arm movement (target fixation + reaching). In the third task, the monkey made a saccade to the target without any arm movement (saccade). Finally, in the fourth task, the monkey first made a saccade to the target, then reached to it after a delay (saccade + reaching). This design allowed us to examine the contribution of the oculomotor context to arm-related neuronal activity in PMd. We analyzed the effects of the task type on neuronal activity and found that many cells showed a task effect during the signal (26/60; 43%), set (16/49; 33%) and/or movement (15/54; 28%) epochs, depending on the oculomotor history. These findings, together with previously published data, suggest that PMd codes limb-movement direction in a gaze-dependent manner and may, thus, play an important role in the brain mechanisms of eye-hand coordination during visually guided reaching. PMID:10473760

  3. Eye-Hand Coordination: Dexterous Object Manipulation in New Gravity Fields

    NASA Astrophysics Data System (ADS)

    Thonnard, J. L.; Smith, A.; Wing, A.; McIntyre, J.; Lefèvre, P.; White, O.; Augurelle, A. S.; Langlais, J. S.; Witney, A.; Blohm, G.; Penta, M.; Elmann-Larsen, B.; Bracewell, R. M.; Stramigioli, S.

    2005-06-01

    the effects of a change in gravity on the dynamics of prehension, on the kinematics of upper limb movements and on eye-hand coordination. This report describes the results of some experiments already performed and the scientific objectives of the experiments that will be carried out in the coming years.

  4. [The psychomotor test for research of eye-hand coordination at performance of monotonous activity on tracking target].

    PubMed

    Dorokhov, V B; Arsen'ev, G N; Tkachenko, O N; Zakharchenko, D V; Lavrova, T P; Dementienko, V V

    2011-01-01

    Visual-motor coordination is necessary for successful performance of everyday activities. Many tasks, such as driving or operating devices in the workplace, require a variety of coordination patterns with different levels of compatibility between the eyes and the hand. The psychomotor test was developed which makes it possible to analyze visual-motor coordination disorders caused by a decrease in the level of wakefulness. A small circular target (14 mm in diameter) was moving with a low constant velosity (12 mm/s) in a circular trajectory (80 mm in diameter) with a period of 20 s. Subjects were instructed to keep the mouse-driven cursor inside a target, overstepping the limits of the moving target was considered as an error. To test the attention level, an additional stimulus was introduced which appeared for 3 seconds with an interval of 15 to 40 s. When the stimulus appeared, it was required to touch it with the cursor and click the mouse button. Cursor trajectories have a temporal resolution of 120 Hz. Eye movements were recorded with a PC-based Eyegaze Development System (LC Technologies, USA) measuring corneal reflectance with a collection rate of 120 Hz. Monotonous character of the test performance induced drowsiness and led to errors 25-30 minutes after the beginning of the experiment. Changes in physiological vigilance level was evaluated with EEG recording. Analysis of the dynamic characteristics of smooth and saccadic eye movements and hand movements showed their high sensitivity to a decrease in efficiency of operator's activity caused by a drop in the level of wakefulness. It is suggested that further development of this approach to measuring eye-hand coordination will promote working out a contactless method for the express diagnostics of the critical levels of drowsiness as well as for the definition of professional characteristics of an operator. PMID:21961322

  5. Gain-of-Function Mutations in the KATP Channel (KCNJ11) Impair Coordinated Hand-Eye Tracking

    PubMed Central

    McTaggart, James S.; Jenkinson, Ned; Brittain, John-Stuart; Greeley, Siri A. W.; Hattersley, Andrew T.; Ashcroft, Frances M.

    2013-01-01

    Background 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. Methods 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. Results 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. Conclusions 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. PMID:23626843

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

    PubMed

    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. PMID:25394882

  7. Development of a model of machine hand eye coordination and program specifications for a topological machine vision system

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A unified approach to computer vision and manipulation is developed which is called choreographic vision. In the model, objects to be viewed by a projected robot in the Viking missions to Mars are seen as objects to be manipulated within choreographic contexts controlled by a multimoded remote, supervisory control system on Earth. A new theory of context relations is introduced as a basis for choreographic programming languages. A topological vision model is developed for recognizing objects by shape and contour. This model is integrated with a projected vision system consisting of a multiaperture image dissector TV camera and a ranging laser system. System program specifications integrate eye-hand coordination and topological vision functions and an aerospace multiprocessor implementation is described.

  8. Adaptive Responses in Eye-Head-Hand Coordination Following Exposures to a Virtual Environment as a Possible Space Flight Analog

    NASA Technical Reports Server (NTRS)

    Harm, Deborah L.; Taylor, L. C.; Bloomberg, J. J.

    2007-01-01

    Virtual environments (VE) offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Sensorimotor aftereffects of VEs are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. The purpose of this research was to compare disturbances in sensorimotor coordination produced by dome virtual environment display and to examine the effects of exposure duration, and repeated exposures to VR systems. The current study examined disturbances in eye-head-hand (EHH) and eye-head coordination. Preliminary results will be presented. Eleven subjects have participated in the study to date. One training session was completed in order to achieve stable performance on the EHH coordination and VE tasks. Three experimental sessions were performed each separated by one day. Subjects performed a navigation and pick and place task in a dome immersive display VE for 30 or 60 min. The subjects were asked to move objects from one set of 15 pedestals to the other set across a virtual square room through a random pathway as quickly and accurately as possible. EHH coordination was measured before, immediately after, and at 1 hr, 2 hr, 4 hr and 6 hr following exposure to VR. EHH coordination was measured as position errors and reaction time in a pointing task that included multiple horizontal and vertical LED targets. Repeated measures ANOVAs were used to analyze the data. In general, we observed significant increases in position errors for both horizontal and vertical targets. The largest decrements were observed immediately following exposure to VR and showed a fairly rapid recovery across test sessions, but not across days. Subjects generally showed faster RTs across days. Individuals recovered from the detrimental effects of exposure to the VE on position errors within 1-2 hours. The fact that subjects did not significantly improve across days

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

    NASA Astrophysics Data System (ADS)

    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

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

    PubMed Central

    Shin, Ji-won; Song, Gui-bin; Hwangbo, Gak

    2015-01-01

    [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. PMID:26311943

  11. System for projection of a three-dimensional, moving virtual target for studies of eye-hand coordination.

    PubMed

    Schneider, W; Harris, T J; Feldberg, I E; Massey, J T; Georgopoulos, A P; Meyer, R A

    1995-11-01

    Eye-hand tracking of moving visual objects in three-dimensional (3D) space is common in the behavioral repertoire of primates. However, behavioral and/or neurophysiological studies of this function are lacking mainly because devices do not exist that allow its investigation. We describe a device by which a spot of light can be presented in the immediate extrapersonal space of a subject and can be moved in various trajectories in 3D space. The target is a real image of a circular aperture produced by a system consisting of a light source, aperture, filters, several lenses and fold mirrors, and a large concave mirror to focus the final real image. Rapid, computer-controlled movement of the image is obtained by tilting a gimbal-mounted guide mirror (for x and y motion) and by translating a lens (for motion in the z direction). A second configuration of the system allows movement of a 3D image in the 3D space. Hand motion is monitored by means of a sonic, 3D, position-measurement system. PMID:8750095

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

    PubMed

    Faber, Irene R; Oosterveld, Frits G J; Nijhuis-Van der Sanden, Maria 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 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. PMID:24465638

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

    PubMed Central

    Faber, Irene R.; Oosterveld, Frits G. J.; Nijhuis-Van der Sanden, Maria 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 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. PMID:24465638

  14. 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.

    PubMed

    Fong, Shirley S M; Ng, Shamay S M; Cheng, Yoyo T Y; Wong, Janet Y H; Yu, Esther Y T; Chow, Gary C C; Chak, Yvonne T C; Chan, Ivy K Y; Zhang, Joni; Macfarlane, Duncan; Chung, Louisa M Y

    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

  15. 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

    PubMed Central

    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

  16. Teaching Skills to Use a Computer Mouse in Preschoolers with Developmental Disabilities: Shaping Moving a Mouse and Eye-Hand Coordination

    ERIC Educational Resources Information Center

    Shimizu, Hirofumi; Yoon, Soyoung; McDonough, Christopher S.

    2010-01-01

    We taught seven preschoolers with developmental disabilities to point-and-click with a computer mouse. The computer-based training program consisted of three parts, based on a task analysis of the behavioral prerequisites to point-and-click. Training 1 was designed to shape moving the mouse. Training 2 was designed to build eye-hand coordination…

  17. Hand-Eye Calibration of Robonaut

    NASA Technical Reports Server (NTRS)

    Nickels, Kevin; Huber, Eric

    2004-01-01

    NASA's Human Space Flight program depends heavily on Extra-Vehicular Activities (EVA's) performed by human astronauts. EVA is a high risk environment that requires extensive training and ground support. In collaboration with the Defense Advanced Research Projects Agency (DARPA), NASA is conducting a ground development project to produce a robotic astronaut's assistant, called Robonaut, that could help reduce human EVA time and workload. The project described in this paper designed and implemented a hand-eye calibration scheme for Robonaut, Unit A. The intent of this calibration scheme is to improve hand-eye coordination of the robot. The basic approach is to use kinematic and stereo vision measurements, namely the joint angles self-reported by the right arm and 3-D positions of a calibration fixture as measured by vision, to estimate the transformation from Robonaut's base coordinate system to its hand coordinate system and to its vision coordinate system. Two methods of gathering data sets have been developed, along with software to support each. In the first, the system observes the robotic arm and neck angles as the robot is operated under external control, and measures the 3-D position of a calibration fixture using Robonaut's stereo cameras, and logs these data. In the second, the system drives the arm and neck through a set of pre-recorded configurations, and data are again logged. Two variants of the calibration scheme have been developed. The full calibration scheme is a batch procedure that estimates all relevant kinematic parameters of the arm and neck of the robot The daily calibration scheme estimates only joint offsets for each rotational joint on the arm and neck, which are assumed to change from day to day. The schemes have been designed to be automatic and easy to use so that the robot can be fully recalibrated when needed such as after repair, upgrade, etc, and can be partially recalibrated after each power cycle. The scheme has been implemented on

  18. How your hand drives my eyes

    PubMed Central

    Ambrosini, Ettore; Cardellicchio, Pasquale; Sinigaglia, Corrado

    2014-01-01

    When viewing object-related hand actions people make proactive eye movements of the same kind as those made when performing such actions. Why is this so? It has been suggested that proactive gaze when viewing a given hand action depends on the recruitment of motor areas such as the ventral premotor (PMv) cortex that would be involved in the execution of that action. However, direct evidence for a distinctive role of the PMv cortex in driving gaze behavior is still lacking. We recorded eye moments while viewing hand actions before and immediately after delivering repetitive transcranial magnetic stimulation (rTMS) over the left PMv and the posterior part of the left superior temporal sulcus, which is known to be involved in high-order visual action processing. Our results showed that rTMS-induced effects were selective with respect to the viewed actions following the virtual lesion of the left PMv only. This, for the first time, provides direct evidence that the PMv cortex might selectively contribute to driving the viewer’s gaze to the action’s target. When people view another’s action, their eyes may be driven by motor processes similar to those they would need to perform the action themselves. PMID:23559593

  19. Visuomotor impairment in early-stage Alzheimer's disease: changes in relative timing of eye and hand movements.

    PubMed

    Verheij, Simone; Muilwijk, Danya; Pel, Johan J M; van der Cammen, Tischa J M; Mattace-Raso, Francesco U S; van der Steen, Johannes

    2012-01-01

    Although memory complaints are one of the first clinical symptoms in patients with Alzheimer's disease (AD), damage to the parietal lobe, a key structure in the visuomotor coordination network, was recently identified in early-stage AD. The aim of this study was to quantify visuomotor coordination in patients with probable AD and to compare their visuomotor performance with controls using five eye-hand coordination tasks of variable complexity. Eye and hand movements were measured in 16 AD patients and 18 controls. The measurement setup consisted of a touch screen, an eye-tracking device, and a motion capturing system. We investigated eye-hand coordination by quantifying absolute and relative latencies of eye and hand movements and by analyzing eye and hand kinematics. We found that AD patients need significantly more time to initiate and execute goal-directed hand movements. AD patients are also unable to suppress reflexive eye and, to a lesser extent, hand movements. Furthermore, AD patients use a stepwise approach of eye and hand movements to touch a sequence of stimuli, whereas controls more often show an anticipatory approach. The impairments in reflex suppression of eye and hand movements, and changes in relative timing of eye-hand coordination, in AD patients support the notion that cortical networks involving the posterior parietal cortex are affected at an early disease-stage. It also suggests that the problems of AD patients to perform daily activities that require eye-hand coordination are not only caused by cognitive decline, but also by degeneration of neural networks involved in visuomotor coordination. PMID:22377783

  20. Keep an Eye on the Hand

    ERIC Educational Resources Information Center

    Zoller, Kendall

    2004-01-01

    Nonverbal communication--how we use our voices, breathing, bodies, and eyes--is as powerful as our words. As much as 82% of our message is conveyed through nonverbal strategies. Learning to use these cues can be key to improving our ability to facilitate or lead meetings.

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

    PubMed Central

    Mrotek, Leigh Ann

    2013-01-01

    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. PMID:23552996

  2. Natural coordinates for specification of eye movements.

    PubMed

    Clement, R A

    1991-01-01

    Tweed and Vilis (Journal of Neurophysiology, 58, 832-849, 1987) have argued that quaternion algebra provides the most appropriate description of the rotations of the eye, and have derived a three-dimensional model of gaze control based on quaternion operations. Euler angles give a simpler description of the rotations of the eye, and can also be used to formulate an alternative version of the three-dimensional gaze control model. Comparison of the two versions of the model highlights the distinction between the functional predictions of the model, and the predictions which depend only on the choice of mathematical descriptions. PMID:1771787

  3. Effect of hand paddles and parachute on butterfly coordination.

    PubMed

    Telles, Thiago; Barroso, Renato; Barbosa, Augusto Carvalho; Salgueiro, Diego Fortes de Souza; Colantonio, Emilson; Andries Júnior, Orival

    2015-01-01

    This study investigated the effects of hand paddles, parachute and hand paddles plus parachute on the inter-limb coordination of butterfly swimming. Thirteen male swimmers were evaluated in four random maximal intensity conditions: without equipment, with hand paddles, with parachute and with hand paddles + parachute. Arm and leg stroke phases were identified by 2D video analysis to calculate the total time gap (T1: time between hands' entry in the water and high break-even point of the first undulation; T2: time between the beginning of the hand's backward movement and low break-even point of the first undulation; T3: time between the hand's arrival in a vertical plane to the shoulders and high break-even point of the second undulation; T4: time between the hand's release from the water and low break-even point of the second undulation). The swimming velocity was reduced and T1, T2 and T3 increased in parachute and hand paddles + parachute. No changes were observed in T4. Total time gap decreased in parachute and hand paddles + parachute. It is concluded that hand paddles do not influence the arm-to-leg coordination in butterfly, while parachute and hand paddles + parachute do change it, providing a greater propulsive continuity. PMID:25583184

  4. Prevention of coordinated eye movements and steering impairs driving performance.

    PubMed

    Marple-Horvat, D E; Chattington, M; Anglesea, M; Ashford, D G; Wilson, M; Keil, D

    2005-06-01

    When approaching a bend in the road, a driver looks across to the inside kerb before turning the steering wheel. Eye movements and steering are tightly linked, with the eyes leading, which means that the oculomotor controller can assist the neural centres controlling steering. This optimum coordination is observed for all drivers; but despite being the preferred solution to the motor-control problem of successfully steering along a winding road, the question remains as to how crucial such coordinated eye and steering movements are for driving performance. Twenty subjects repeatedly drove a simulated stage of the World Rally Championship, aiming to complete the course in the fastest possible time. For the first six repetitions they used the usual coordination of eye movements and steering; for drives 7--12 they were instructed to fixate on a small spot in the centre of the screen (centre gaze). Prevention of coordination in this way impaired their performance (drives 6 and 7 compared), dramatically increasing their time taken to complete the course, equivalent to slipping 19 places down the leader board in the actual rally stage. This indicates that the usual pattern of eye movements correlated with steering is crucial for driving performance. Further experiments are suggested to reveal whether any attentional demand associated with keeping the eyes still contributes to the loss in performance. PMID:15841399

  5. Automated tracking and grasping of a moving object with a robotic hand-eye system

    SciTech Connect

    Allen, P.K.; Timcenko, A.; Yoshimi, B.; Michelman, P. . Dept. of Computer Science)

    1993-04-01

    Most robotic grasping tasks assume a stationary or fixed object. In this paper, the authors explore the requirements for tracking and grasping a moving object. The focus of the work is to achieve a high level of interaction between a real-time vision system capable of tracking moving objects in 3-D and a robot arm with gripper that can be used to pick up a moving object. There is an interest in exploring the interplay of hand--eye coordination for dynamic grasping takes such as grasping of parts on a moving conveyor system, assembly of articulated parts, or for grasping from a mobile robotic system. Coordination between an organisms sensing modalities and motor control system is a hallmark of intelligent behavior, and they are pursuing the goal of building an integrated sensing and actuation system that can operate in dynamic as opposed to static environments. The system they have built addresses three distinct problems in robotic hand--eye coordination for grasping moving objects: fast computation of 3-D motion parameters from vision, predictive control of a moving robotic arm to track a moving object, and interception and grasping. The system is able to operate at approximately human arm movement rates, and experimental results in which a moving model train is tracked is presented, stably grasped, and picked up by the system. The algorithms they have developed that relate sensing to actuation are quite general and applicable to a variety of complex robotic tasks that require visual feedback for arm and hand control.

  6. Active head rotations and eye-head coordination

    NASA Technical Reports Server (NTRS)

    Zangemeister, W. H.; Stark, L.

    1981-01-01

    It is pointed out that head movements play an important role in gaze. The interaction between eye and head movements involves both their shared role in directing gaze and the compensatory vestibular ocular reflex. The dynamics of head trajectories are discussed, taking into account the use of parameterization to obtain the peak velocity, peak accelerations, the times of these extrema, and the duration of the movement. Attention is given to the main sequence, neck muscle EMG and details of the head-movement trajectory, types of head model accelerations, the latency of eye and head movement in coordinated gaze, gaze latency as a function of various factors, and coordinated gaze types. Clinical examples of gaze-plane analysis are considered along with the instantaneous change of compensatory eye movement (CEM) gain, and aspects of variability.

  7. Processing Coordinate Structures in Chinese: Evidence from Eye Movements

    PubMed Central

    Qingrong, Chen; Yan, Huang

    2012-01-01

    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. PMID:22558163

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

    PubMed

    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. PMID:24792218

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

    NASA Astrophysics Data System (ADS)

    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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  11. Corticospinal Excitability in the Hand Muscles is Decreased During Eye Movement with Visual Occlusion.

    PubMed

    Chujo, Yuta; Jono, Yasutomo; Tani, Keisuke; Nomura, Yoshifumi; Hiraoka, Koichi

    2016-02-01

    Corticospinal excitability in the hand muscles decreases during smooth pursuit eye movement. The present study tested a hypothesis that the decrease in corticospinal excitability in the hand muscles at rest during eye movement is not caused by visual feedback but caused by motor commands to the eye muscles. Healthy men (M age = 28.4 yr., SD = 5.2) moved their eyes to the right with visual occlusion (dark goggles) while their arms and hands remained at rest. The motor-evoked potential in the hand muscles was suppressed by 19% in the third quarter of the eye-movement period, supporting a view that motor commands to the eye muscles are the cause of the decrease in corticospinal excitability in the hand muscles. The amount of the suppression was not significantly different among the muscles, indicating that modulation of corticospinal excitability in one muscle induced by eye movement is not dependent on whether eye movement direction and the direction of finger movement when the muscle contracts are identical. Thus, the finding failed to support a hypothetical view that motor commands to the eye muscles concomittantly produce motor commands to the hand muscles. Moreover, the amount of the suppression was not significantly different between the forearm positions, indicating that the suppression was not affected by proprioception of the forearm muscles when visual feedback is absent. PMID:27420319

  12. Eye Selector Logic for a Coordinated Cell Cycle Exit

    PubMed Central

    Lopes, Carla S.; Casares, Fernando

    2015-01-01

    Organ-selector transcription factors control simultaneously cell differentiation and proliferation, ensuring the development of functional organs and their homeostasis. How this is achieved at the molecular level is still unclear. Here we have investigated how the transcriptional pulse of string/cdc25 (stg), the universal mitotic trigger, is regulated during Drosophila retina development as an example of coordinated deployment of differentiation and proliferation programs. We identify the eye specific stg enhancer, stg-FMW, and show that Pax6 selector genes, in cooperation with Eya and So, two members of the retinal determination network, activate stg-FMW, establishing a positive feed-forward loop. This loop is negatively modulated by the Meis1 protein, Hth. This regulatory logic is reminiscent of that controlling the expression of differentiation transcription factors. Our work shows that subjecting transcription factors and key cell cycle regulators to the same regulatory logic ensures the coupling between differentiation and proliferation programs during organ development. PMID:25695251

  13. Specific eye-head coordination enhances vision in progressive lens wearers.

    PubMed

    Rifai, Katharina; Wahl, Siegfried

    2016-09-01

    In uncorrected vision all combinations of eye and head positions are visually equivalent; thus, there is no need for a specific modification of eye-head coordination in young healthy observers. In contrast, the quality of visual input indeed strongly depends on eye position in the majority of healthy elderly drivers, namely in progressive additional lens (PALs) wearers. For a given distance, only specific combinations of eye and head position provide clear vision in a progressive lens wearer. However, although head movements are an integral part of gaze behavior, it is not known if eye-head coordination takes part in the enhancement of visual input in healthy individuals. In the current study we determined changes in eye-head coordination in progressive lens wearers in challenging tasks with high cognitive load, in the situation of driving. During a real-world drive on an urban round track in Stuttgart, gaze movements and head movements were measured in 17 PAL wearers and eye-head coordination was compared to 27 controls with unrestricted vision. Head movement behavior, specific to progressive lens wearers, was determined in head gain and temporal properties of head movements. Furthermore, vertical eye-head coordination was consistent only among PAL wearers. The observed differences in eye-head coordination clearly demonstrate a contribution of head movements in the enhancement of visual input in the healthy human visual system. PMID:27604068

  14. An Eye in the Palm of Your Hand: Alterations in Visual Processing Near the Hand, a Mini-Review.

    PubMed

    Perry, Carolyn J; Amarasooriya, Prakash; Fallah, Mazyar

    2016-01-01

    Feedback within the oculomotor system improves visual processing at eye movement end points, also termed a visual grasp. We do not just view the world around us however, we also reach out and grab things with our hands. A growing body of literature suggests that visual processing in near-hand space is altered. The control systems for moving either the eyes or the hands rely on parallel networks of fronto-parietal regions, which have feedback connections to visual areas. Since the oculomotor system effects on visual processing occur through feedback, both through the motor plan and the motor efference copy, a parallel system where reaching and/or grasping motor-related activity also affects visual processing is likely. Areas in the posterior parietal cortex, for example, receive proprioceptive and visual information used to guide actions, as well as motor efference signals. This trio of information channels is all that would be necessary to produce spatial allocation of reach-related visual attention. We review evidence from behavioral and neurophysiological studies that support the hypothesis that feedback from the reaching and/or grasping motor control networks affects visual processing while noting ways in which it differs from that seen within the oculomotor system. We also suggest that object affordances may represent the neural mechanism through which certain object features are selected for preferential processing when stimuli are near the hand. Finally, we summarize the two effector-based feedback systems and discuss how having separate but parallel effector systems allows for efficient decoupling of eye and hand movements. PMID:27148034

  15. An Eye in the Palm of Your Hand: Alterations in Visual Processing Near the Hand, a Mini-Review

    PubMed Central

    Perry, Carolyn J.; Amarasooriya, Prakash; Fallah, Mazyar

    2016-01-01

    Feedback within the oculomotor system improves visual processing at eye movement end points, also termed a visual grasp. We do not just view the world around us however, we also reach out and grab things with our hands. A growing body of literature suggests that visual processing in near-hand space is altered. The control systems for moving either the eyes or the hands rely on parallel networks of fronto-parietal regions, which have feedback connections to visual areas. Since the oculomotor system effects on visual processing occur through feedback, both through the motor plan and the motor efference copy, a parallel system where reaching and/or grasping motor-related activity also affects visual processing is likely. Areas in the posterior parietal cortex, for example, receive proprioceptive and visual information used to guide actions, as well as motor efference signals. This trio of information channels is all that would be necessary to produce spatial allocation of reach-related visual attention. We review evidence from behavioral and neurophysiological studies that support the hypothesis that feedback from the reaching and/or grasping motor control networks affects visual processing while noting ways in which it differs from that seen within the oculomotor system. We also suggest that object affordances may represent the neural mechanism through which certain object features are selected for preferential processing when stimuli are near the hand. Finally, we summarize the two effector-based feedback systems and discuss how having separate but parallel effector systems allows for efficient decoupling of eye and hand movements. PMID:27148034

  16. Biomechanical Characteristics of Hand Coordination in Grasping Activities of Daily Living

    PubMed Central

    Liu, Ming-Jin; Xiong, Cai-Hua; Xiong, Le; Huang, Xiao-Lin

    2016-01-01

    Hand coordination can allow humans to have dexterous control with many degrees of freedom to perform various tasks in daily living. An important contributing factor to this important ability is the complex biomechanical architecture of the human hand. However, drawing a clear functional link between biomechanical architecture and hand coordination is challenging. It is not understood which biomechanical characteristics are responsible for hand coordination and what specific effect each biomechanical characteristic has. To explore this link, we first inspected the characteristics of hand coordination during daily tasks through a statistical analysis of the kinematic data, which were collected from thirty right-handed subjects during a multitude of grasping tasks. Then, the functional link between biomechanical architecture and hand coordination was drawn by establishing the clear corresponding causality between the tendinous connective characteristics of the human hand and the coordinated characteristics during daily grasping activities. The explicit functional link indicates that the biomechanical characteristic of tendinous connective architecture between muscles and articulations is the proper design by the Creator to perform a multitude of daily tasks in a comfortable way. The clear link between the structure and the function of the human hand also suggests that the design of a multifunctional robotic hand should be able to better imitate such basic architecture. PMID:26730579

  17. Biomechanical Characteristics of Hand Coordination in Grasping Activities of Daily Living.

    PubMed

    Liu, Ming-Jin; Xiong, Cai-Hua; Xiong, Le; Huang, Xiao-Lin

    2016-01-01

    Hand coordination can allow humans to have dexterous control with many degrees of freedom to perform various tasks in daily living. An important contributing factor to this important ability is the complex biomechanical architecture of the human hand. However, drawing a clear functional link between biomechanical architecture and hand coordination is challenging. It is not understood which biomechanical characteristics are responsible for hand coordination and what specific effect each biomechanical characteristic has. To explore this link, we first inspected the characteristics of hand coordination during daily tasks through a statistical analysis of the kinematic data, which were collected from thirty right-handed subjects during a multitude of grasping tasks. Then, the functional link between biomechanical architecture and hand coordination was drawn by establishing the clear corresponding causality between the tendinous connective characteristics of the human hand and the coordinated characteristics during daily grasping activities. The explicit functional link indicates that the biomechanical characteristic of tendinous connective architecture between muscles and articulations is the proper design by the Creator to perform a multitude of daily tasks in a comfortable way. The clear link between the structure and the function of the human hand also suggests that the design of a multifunctional robotic hand should be able to better imitate such basic architecture. PMID:26730579

  18. Research on acquisition of 3D information using eye-in-hand robot system

    NASA Astrophysics Data System (ADS)

    You, Bo; Wang, Pengfei

    2001-09-01

    In this paper, a PUMA562 robot, a micro CCD camera and an image acquisition card, along with IBM/PC 586 host computer, formed eye-in-hand visual servoing experimental system of an intelligent space robot. A novel robot visual servo control method is adopted, based on FMF neural network. Computer simulation and many experiments of object tracking with the capture of floating object were carried out in this eye-in- hand visual servoing system. It is an important reference to further research in the future.

  19. Eye-head coordination during large gaze shifts.

    PubMed

    Tweed, D; Glenn, B; Vilis, T

    1995-02-01

    1. Three-dimensional (3D) eye and head rotations were measured with the use of the magnetic search coil technique in six healthy human subjects as they made large gaze shifts. The aims of this study were 1) to see whether the kinematic rules that constrain eye and head orientations to two degrees of freedom between saccades also hold during movements; 2) to chart the curvature and looping in eye and head trajectories; and 3) to assess whether the timing and paths of eye and head movements are more compatible with a single gaze error command driving both movements, or with two different feedback loops. 2. Static orientations of the eye and head relative to space are known to resemble the distribution that would be generated by a Fick gimbal (a horizontal axis moving on a fixed vertical axis). We show that gaze point trajectories during eye-head gaze shifts fit the Fick gimbal pattern, with horizontal movements following straight "line of latitude" paths and vertical movements curving like lines of longitude. However, horizontal (and to a lesser extent vertical) movements showed direction-dependent looping, with rightward and leftward (and up and down) saccades tracing slightly different paths. Plots of facing direction (the analogue of gaze direction for the head) also showed the latitude/longitude pattern, without looping. In radial saccades, the gaze point initially moved more vertically than the target direction and then curved; head trajectories were straight. 3. The eye and head components of randomly sequenced gaze shifts were not time locked to one another. The head could start moving at any time from slightly before the eye until 200 ms after, and the standard deviation of this interval could be as large as 80 ms. The head continued moving for a long (up to 400 ms) and highly variable time after the gaze error had fallen to zero. For repeated saccades between the same targets, peak eye and head velocities were directly, but very weakly, correlated; fast eye

  20. Dynamic Assessment of Binocular Eye Movement Coordination: Norms and Functional Implications

    PubMed Central

    Viirre, Erik

    2014-01-01

    Alignment of the two eyes is controlled by a finely tuned, fast acting system with components within the brain. Assessment of binocular alignment has classically been done statically. Eye positions are assessed in primary position and at eccentric angles to interpret the functional status of the oculomotor nerves and muscles. However, assessment of dynamic eye alignment, the coordination of the eyes during eye movements, has been less commonly carried out and has not been formalized with population norms. Clinicians are aware of slow eye movement dynamic alignment changes, such as that clinically observed in Intranuclear Ophthalmoplegia. But assessment of eye alignment during rapid eye movements, such as saccade or pursuit has not been part of neuro-ophthalmologic assessment. With the advent of inexpensive, high resolution recording systems, both eyes can be simultaneously recorded and their coordination during movement compared. Thus, we now have an opportunity to provide a laboratory based objective measurement of a gamut of binocular coordination systems. Recent research in humans has demonstrated increased variability of binocular coordination during divided attention. Variability is an interesting statistic that can be sensitively assessed in the velocity domain without extensive gaze position recalibration procedures during recording over long intervals. Variability can thus be used as a robust, long-term eye movement parameter with minimal intrusiveness to the subject. It is proposed that population studies of binocular coordination during eye movements be carried out to determine neurologic norms so that conditions such as brain injury and others can be assessed with a functional tool with objective parameters. PMID:24804278

  1. Review and Evaluation of Hand-Arm Coordinate Systems for Measuring Vibration Exposure, Biodynamic Responses, and Hand Forces.

    PubMed

    Dong, Ren G; Sinsel, Erik W; Welcome, Daniel E; Warren, Christopher; Xu, Xueyan S; McDowell, Thomas W; Wu, John Z

    2015-09-01

    The hand coordinate systems for measuring vibration exposures and biodynamic responses have been standardized, but they are not actually used in many studies. This contradicts the purpose of the standardization. The objectives of this study were to identify the major sources of this problem, and to help define or identify better coordinate systems for the standardization. This study systematically reviewed the principles and definition methods, and evaluated typical hand coordinate systems. This study confirms that, as accelerometers remain the major technology for vibration measurement, it is reasonable to standardize two types of coordinate systems: a tool-based basicentric (BC) system and an anatomically based biodynamic (BD) system. However, these coordinate systems are not well defined in the current standard. Definition of the standard BC system is confusing, and it can be interpreted differently; as a result, it has been inconsistently applied in various standards and studies. The standard hand BD system is defined using the orientation of the third metacarpal bone. It is neither convenient nor defined based on important biological or biodynamic features. This explains why it is rarely used in practice. To resolve these inconsistencies and deficiencies, we proposed a revised method for defining the realistic handle BC system and an alternative method for defining the hand BD system. A fingertip-based BD system for measuring the principal grip force is also proposed based on an important feature of the grip force confirmed in this study. PMID:26929824

  2. Eye-head coordination during optokinetic stimulation in squirrel monkeys

    NASA Technical Reports Server (NTRS)

    Kubo, T.; Igarashi, M.; Jensen, D. W.; Homick, J. L.

    1981-01-01

    Head and eye movements in the yaw plane were recorded during and after optokinetic stimulation in squirrel monkeys. 1) Phasic or tonic head deviations to the side of the ocular quick phase occurred in 94% of total recordings (n = 50) during the perstimulus period, and in 75% of recordings (n = 49) during the poststimulus period. Magnitude of mean head deviation was significantly different between perstimulus and poststimulus periods. 2) Head nystagmus associated with eye nystagmus was consistently observed in seven of nine squirrel monkeys during optokinetic stimulation. Squirrel monkeys are thereby less prone to display head nystagmus than either guinea pigs, pigeons or chickens. 3) Slow phase speeds of coupled head and eye nystagmus were subjected to statistical analysis. A highly significant negative correlation was found between slow phase head and eye speeds. The correlation coefficient was - 0.81 at 60 degrees / sec stimulus (n = 119) and -0.72 at 100 degrees / sec stimulus (n = 131). The gaze speed, calculated by summing the head and eye speeds, was 59.1 plus or minus 6.8 / sec at 60 degrees / sec and 92.2 plus or minus 11.4 at 100 degrees / sec stimulus. There was no significant difference between the gaze speed in a free head condition and the eye speed when the head was fixed.

  3. The relative timing between eye and hand in rapid sequential pointing is affected by time pressure, but not by advance knowledge.

    PubMed

    Deconinck, F J A; van Polanen, V; Savelsbergh, G J P; Bennett, S J

    2011-08-01

    The present study examined the effect of timing constraints and advance knowledge on eye-hand coordination strategy in a sequential pointing task. Participants were required to point at two successively appearing targets on a screen while the inter-stimulus interval (ISI) and the trial order were manipulated, such that timing constraints were high (ISI = 300 ms) or low (ISI = 450 ms) and advance knowledge of the target location was present (fixed order) or absent (random order). Analysis of eye and finger onset and completion times per segment of the sequence indicated that oculo-manual behaviour was in general characterized by eye movements preceding the finger, as well as 'gaze anchoring' (i.e. eye fixation of the first target until completion of the finger movement towards that target). Advance knowledge of future target locations lead to shorter latency times of eye and hand, and smaller eye-hand lead times, which in combination resulted in shorter total movement times. There was, however, no effect of advance knowledge on the duration of gaze anchoring. In contrast, gaze anchoring did change as a function of the interval between successive stimuli and was shorter with a 300 ms ISI versus 450 ms ISI. Further correlation analysis provided some indication that shorter residual latency is associated with shorter pointing duration, without affecting accuracy. These results are consistent with a neural mechanism governing the coupling of eye and arm movements, which has been suggested to reside in the superior colliculus. The temporal coordination resulting from this coupling is a function of the time pressure on the visuo-manual system resulting from the appearance of external stimuli. PMID:21744087

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

    ERIC Educational Resources Information Center

    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…

  5. Radiation exposure of eyes, thyroid gland and hands in orthopaedic staff: a systematic review

    PubMed Central

    2012-01-01

    Background Various procedures, especially minimal invasive techniques using fluoroscopy, pose a risk of radiation exposure to orthopaedic staff. Anatomical sites such as the eyes, thyroid glands and hands are more vulnerable to radiation considering the limited use of personal protective devices in the workplace. The objective of the study is to assess the annual mean cumulative and per procedure radiation dose received at anatomical locations like eyes, thyroid glands and hands in orthopaedic staff using systematic review. Methods The review of literature was conducted using systematic search of the database sources like PUBMED and EMBASE using appropriate keywords. The eligibility criteria and the data extraction of literature were based on study design (cohort or cross-sectional study), study population (orthopaedic surgeons or their assistants), exposure (doses of workplace radiation exposure at hands/fingers, eye/forehead, neck/thyroid), language (German and English). The literature search was conducted using a PRISMA checklist and flow chart. Results Forty-two articles were found eligible and included for the review. The results show that radiation doses for the anatomical locations of eye, thyroid gland and hands were lower than the dose levels recommended. But there is a considerable variation of radiation dose received at all three anatomical locations mainly due to different situations including procedures (open and minimally invasive), work experience (junior and senior surgeons),distance from the primary and secondary radiation, and use of personal protective equipments (PPEs). The surgeons receive higher radiation dose during minimally invasive procedures compared to open procedures. Junior surgeons are at higher risk of radiation exposure compared to seniors. PPEs play a significant role in reduction of radiation dose. Conclusions Although the current radiation precautions appear to be adequate based on the low dose radiation, more in-depth studies

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

    PubMed

    Furneaux, S; Land, M F

    1999-12-01

    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

  7. Head-Torso-Hand Coordination in Children with and without Developmental Coordination Disorder

    ERIC Educational Resources Information Center

    Elders, Vera; Sheehan, Sinead; Wilson, Andrew D.; Levesley, Martin; Bhakta, Bipin; Mon-Williams, Mark

    2010-01-01

    Aim: This study investigated the nature of coordination and control problems in children with developmental coordination disorder (DCD). Method: Seven adults (two males, five females, age range 20-28y; mean 23y, SD 2y 8mo) and eight children with DCD (six males, two females, age range 7-9y; mean 8y, SD 8mo), and 10 without DCD (seven males, three…

  8. Impact of a lead glass screen on scatter radiation to eyes and hands in interventional cardiologists.

    PubMed

    Maeder, Micha; Brunner-La Rocca, Hans Peter; Wolber, Thomas; Ammann, Peter; Roelli, Hans; Rohner, Franziska; Rickli, Hans

    2006-01-01

    The objective of this study was to assess the impact of a transparent lead glass screen (TLGS) on scatter radiation to the eyes and the hands in interventional cardiologists and to compare the results to the recommended annual threshold values of 150 and 500 mSv, respectively. Local radiation doses to the left eye and the ring finger of the left hand of three operators (A, B, C) were assessed by thermoluminiscence dosimeters during 813 coronary angiographies (CAs), including 190 ad hoc percutaneous coronary interventions (PCIs) either with a TLGS placed between patient and operator [615 CAs including 138 ad hoc PCIs; dose-area product (DAP) = 84.9 +/- 71.3 Gy x cm(2)], or without (198 CAs including 52 PCIs; DAP = 85.7 +/- 61.5 Gy x cm(2)). To determine the efficacy of the TLGS, average DAP-normalized local doses were calculated. Using a TLGS, operator A, B, and C performed 259 (in 9 months), 211 (in 8 months), and 145 CAs (in 8 months) with TLGS and acquired cumulative eye lens doses of 5.5, 1.5, and 1.0 mSv corresponding to extrapolated annual doses of 7.3, 2.3, and 1.5 mSv. The cumulative finger doses were 9.6, 10.3, and 6.4 mSv, resulting in extrapolated annual doses of 12.8, 15.5, and 9.6 mSv. Compared to 139 (in 5 months), 36 (in 2 months), and 23 CAs (in 2 months) without TLGS, the use of a TLGS reduced the DAP-normalized eye dose by a factor of 19 (with TLGS 0.153 vs. without TLGS 2.924 microSv/Gy x cm(2)), whereas only a weak effect on the dose to the hands was observed (with TLGS 0.504 vs. without TLGS 0.578 microSv/Gy x cm(2)). The consequent use of a TLGS efficiently reduces scatter radiation to the operator's eyes in daily practice, but has only minimal effects on the dose to the hands. PMID:16273590

  9. Meis1 coordinates a network of genes implicated in eye development and microphthalmia.

    PubMed

    Marcos, Séverine; González-Lázaro, Monica; Beccari, Leonardo; Carramolino, Laura; Martin-Bermejo, Maria Jesus; Amarie, Oana; Mateos-San Martín, Daniel; Torroja, Carlos; Bogdanović, Ozren; Doohan, Roisin; Puk, Oliver; Hrabě de Angelis, Martin; Graw, Jochen; Gomez-Skarmeta, Jose Luis; Casares, Fernando; Torres, Miguel; Bovolenta, Paola

    2015-09-01

    Microphthalmos is a rare congenital anomaly characterized by reduced eye size and visual deficits of variable degree. Sporadic and hereditary microphthalmos have been associated with heterozygous mutations in genes fundamental for eye development. Yet, many cases are idiopathic or await the identification of molecular causes. Here we show that haploinsufficiency of Meis1, which encodes a transcription factor with evolutionarily conserved expression in the embryonic trunk, brain and sensory organs, including the eye, causes microphthalmic traits and visual impairment in adult mice. By combining analysis of Meis1 loss-of-function and conditional Meis1 functional rescue with ChIP-seq and RNA-seq approaches we show that, in contrast to its preferential association with Hox-Pbx BSs in the trunk, Meis1 binds to Hox/Pbx-independent sites during optic cup development. In the eye primordium, Meis1 coordinates, in a dose-dependent manner, retinal proliferation and differentiation by regulating genes responsible for human microphthalmia and components of the Notch signaling pathway. In addition, Meis1 is required for eye patterning by controlling a set of eye territory-specific transcription factors, so that in Meis1(-/-) embryos boundaries among the different eye territories are shifted or blurred. We propose that Meis1 is at the core of a genetic network implicated in eye patterning/microphthalmia, and represents an additional candidate for syndromic cases of these ocular malformations. PMID:26253404

  10. Target modality determines eye-head coordination in nonhuman primates: implications for gaze control

    PubMed Central

    Rajala, Abigail Z.

    2011-01-01

    We have studied eye-head coordination in nonhuman primates with acoustic targets after finding that they are unable to make accurate saccadic eye movements to targets of this type with the head restrained. Three male macaque monkeys with experience in localizing sounds for rewards by pointing their gaze to the perceived location of sources served as subjects. Visual targets were used as controls. The experimental sessions were configured to minimize the chances that the subject would be able to predict the modality of the target as well as its location and time of presentation. The data show that eye and head movements are coordinated differently to generate gaze shifts to acoustic targets. Chiefly, the head invariably started to move before the eye and contributed more to the gaze shift. These differences were more striking for gaze shifts of <20–25° in amplitude, to which the head contributes very little or not at all when the target is visual. Thus acoustic and visual targets trigger gaze shifts with different eye-head coordination. This, coupled to the fact that anatomic evidence involves the superior colliculus as the link between auditory spatial processing and the motor system, suggests that separate signals are likely generated within this midbrain structure. PMID:21795625

  11. Adaptation of eye and hand movements to target displacements of different size.

    PubMed

    Schmitz, Gerd; Bock, Otmar; Grigorova, Valentina; Ilieva, Milena

    2010-06-01

    Previous work has documented that the direction of eye and hand movements can be adaptively modified using the double-step paradigm. Here we report that both motor systems adapt not only to small direction steps (5 degrees gaze angle) but also to large ones (28 degrees gaze angle). However, the magnitude of adaptation did not increase with step size, and the relative magnitude of adaptation therefore decreased from 67% with small steps to 15% with large steps. This decreasing efficiency of adaptation may reflect the participation of directionally selective neural circuits in double-step adaptation. PMID:20424831

  12. Three-dimensional eye-head coordination is implemented downstream from the superior colliculus.

    PubMed

    Klier, Eliana M; Wang, Hongying; Crawford, J Douglas

    2003-05-01

    How the brain transforms two-dimensional visual signals into multi-dimensional motor commands, and subsequently how it constrains the redundant degrees of freedom, are fundamental problems in sensorimotor control. During fixations between gaze shifts, the redundant torsional degree of freedom is determined by various neural constraints. For example, the eye- and head-in-space are constrained by Donders' law, whereas the eye-in-head obeys Listing's law. However, where and how the brain implements these laws is not yet known. In this study, we show that eye and head movements, elicited by unilateral microstimulations of the superior colliculus (SC) in head-free monkeys, obey the same Donders' strategies observed in normal behavior (i.e., Listing's law for final eye positions and the Fick strategy for the head). Moreover, these evoked movements showed a pattern of three-dimensional eye-head coordination, consistent with normal behavior, where the eye is driven purposely out of Listing's plane during the saccade portion of the gaze shift in opposition to a subsequent torsional vestibuloocular reflex slow phase, such that the final net torsion at the end of each head-free gaze shift is zero. The required amount of saccade-related torsion was highly variable, depending on the initial position of the eye and head prior to a gaze shift and the size of the gaze shift, pointing to a neural basis of torsional control. Because these variable, context-appropriate torsional saccades were correctly elicited by fixed SC commands during head-free stimulations, this shows that the SC only encodes the horizontal and vertical components of gaze, leaving the complexity of torsional organization to downstream control systems. Thus we conclude that Listing's and Donders' laws of the eyes and head, and their three-dimensional coordination mechanisms, must be implemented after the SC. PMID:12740415

  13. Muscular coordination of biceps brachii and brachioradialis in elbow flexion with respect to hand position

    PubMed Central

    Kleiber, Tim; Kunz, Leo; Disselhorst-Klug, Catherine

    2015-01-01

    Contribution of synergistic muscles toward specific movements over multi joint systems may change with varying position of distal or proximal joints. Purpose of this study is to reveal the relationship of muscular coordination of brachioradialis and biceps brachii during elbow flexion with respect to hand position and biomechanical advantages and disadvantages of biceps brachii. A group of 16 healthy subjects has been advised to perform 20 repetitions of single elbow flexion movements in different hand positions (pronated, neutral, and supinated). With a speed of 20°/s, simultaneously sEMG of biceps brachii and brachioradialis and kinematics of the movement were recorded in a motion analysis laboratory. Normalized to MVC the sEMG amplitudes of both muscles contributing to elbow flexion movements were compared in pronated, supinated, and neutral hand position over elbow joint angle. Significant differences in the contribution of brachioradialis were found in pronated hand position compared to supinated and neutral hand position while the muscular activity of biceps brachii shows no significant changes in any hand position. In conclusion, a statistical significant dependency of the inter-muscular coordination between biceps brachii and brachioradialis during elbow flexion with respect to hand position has been observed depending on a biomechanical disadvantage of biceps brachii. PMID:26300781

  14. Integration of Hand and Finger Location in External Spatial Coordinates for Tactile Localization

    ERIC Educational Resources Information Center

    Heed, Tobias; Backhaus, Jenny; Roder, Brigitte

    2012-01-01

    Tactile stimulus location is automatically transformed from somatotopic into external spatial coordinates, rendering information about the location of touch in three-dimensional space. This process is referred to as tactile remapping. Whereas remapping seems to occur automatically for the hands and feet, the fingers may constitute an exception in…

  15. The eye in hand: predicting others' behavior by integrating multiple sources of information

    PubMed Central

    Pezzulo, Giovanni; Costantini, Marcello

    2015-01-01

    The ability to predict the outcome of other beings' actions confers significant adaptive advantages. Experiments have assessed that human action observation can use multiple information sources, but it is currently unknown how they are integrated and how conflicts between them are resolved. To address this issue, we designed an action observation paradigm requiring the integration of multiple, potentially conflicting sources of evidence about the action target: the actor's gaze direction, hand preshape, and arm trajectory, and their availability and relative uncertainty in time. In two experiments, we analyzed participants' action prediction ability by using eye tracking and behavioral measures. The results show that the information provided by the actor's gaze affected participants' explicit predictions. However, results also show that gaze information was disregarded as soon as information on the actor's hand preshape was available, and this latter information source had widespread effects on participants' prediction ability. Furthermore, as the action unfolded in time, participants relied increasingly more on the arm movement source, showing sensitivity to its increasing informativeness. Therefore, the results suggest that the brain forms a robust estimate of the actor's motor intention by integrating multiple sources of information. However, when informative motor cues such as a preshaped hand with a given grip are available and might help in selecting action targets, people tend to capitalize on such motor cues, thus turning out to be more accurate and fast in inferring the object to be manipulated by the other's hand. PMID:25568158

  16. The eye in hand: predicting others' behavior by integrating multiple sources of information.

    PubMed

    Ambrosini, Ettore; Pezzulo, Giovanni; Costantini, Marcello

    2015-04-01

    The ability to predict the outcome of other beings' actions confers significant adaptive advantages. Experiments have assessed that human action observation can use multiple information sources, but it is currently unknown how they are integrated and how conflicts between them are resolved. To address this issue, we designed an action observation paradigm requiring the integration of multiple, potentially conflicting sources of evidence about the action target: the actor's gaze direction, hand preshape, and arm trajectory, and their availability and relative uncertainty in time. In two experiments, we analyzed participants' action prediction ability by using eye tracking and behavioral measures. The results show that the information provided by the actor's gaze affected participants' explicit predictions. However, results also show that gaze information was disregarded as soon as information on the actor's hand preshape was available, and this latter information source had widespread effects on participants' prediction ability. Furthermore, as the action unfolded in time, participants relied increasingly more on the arm movement source, showing sensitivity to its increasing informativeness. Therefore, the results suggest that the brain forms a robust estimate of the actor's motor intention by integrating multiple sources of information. However, when informative motor cues such as a preshaped hand with a given grip are available and might help in selecting action targets, people tend to capitalize on such motor cues, thus turning out to be more accurate and fast in inferring the object to be manipulated by the other's hand. PMID:25568158

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

    PubMed Central

    Riordan, Brian; Dye, Melody; Jones, Michael N.

    2015-01-01

    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. PMID:25999900

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

    PubMed

    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. PMID:26289463

  19. The effects of eye coordination during deep cervical flexor training on the thickness of the cervical flexors

    PubMed Central

    Moon, Hyun-Ju; Goo, Bong-Oh; Kwon, Hae-Yeon; Jang, Jun-Hyeok

    2015-01-01

    [Purpose] The purpose of this study was to identify changes in the thicknesses of the cervical flexors according to eye coordination during deep cervical flexor training. [Subjects and Methods] Twenty normal adults were randomly selected, and during their deep cervical flexor training and eye tracking, the thicknesses of the longus colli and the sternocleidomastoid were measured using ultrasonic waves. [Results] The thickness of the longus colli statistically significantly increased when deep cervical flexor training and eye coordination were performed simultaneously. However, the thickness of the sternocleidomastoid did not show statistically significant differences according to eye coordination. [Conclusion] Eye coordination during deep cervical flexor training is likely to increase the thickness of the longus colli selectively. PMID:26834355

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

    PubMed Central

    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 < 0.05) than their age-matched controls (n = 13). 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

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

    NASA Astrophysics Data System (ADS)

    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.

  2. The hand grasps the center, while the eyes saccade to the top of novel objects

    PubMed Central

    Juravle, Georgiana; Velasco, Carlos; Salgado-Montejo, Alejandro; Spence, Charles

    2015-01-01

    In the present study, we investigated whether indenting the sides of novel objects (e.g., product packaging) would influence where people grasp, and hence focus their gaze, under the assumption that gaze precedes grasping. In Experiment 1, the participants grasped a selection of custom-made objects designed to resemble typical packaging forms with an indentation in the upper, middle, or lower part. In Experiment 2, eye movements were recorded while the participants viewed differently-sized (small, medium, and large) objects with the same three indentation positions tested in Experiment 1, together with a control object lacking any indentation. The results revealed that irrespective of the location of the indentation, the participants tended to grasp the mid-region of the object, with their index finger always positioned slightly above its midpoint. Importantly, the first visual fixation tended to fall in the cap region of the novel object. The participants also fixated for longer in this region. Furthermore, participants saccaded more often, as well saccading more rapidly when directing their gaze to the upper region of the objects that they were required to inspect visually. Taken together, these results therefore suggest that different spatial locations on target objects are of interest to our eyes and hands. PMID:26052291

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

    PubMed

    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. PMID:25870160

  4. Three-dimensional eye-head coordination during gaze saccades in the primate.

    PubMed

    Crawford, J D; Ceylan, M Z; Klier, E M; Guitton, D

    1999-04-01

    The purpose of this investigation was to describe the neural constraints on three-dimensional (3-D) orientations of the eye in space (Es), head in space (Hs), and eye in head (Eh) during visual fixations in the monkey and the control strategies used to implement these constraints during head-free gaze saccades. Dual scleral search coil signals were used to compute 3-D orientation quaternions, two-dimensional (2-D) direction vectors, and 3-D angular velocity vectors for both the eye and head in three monkeys during the following visual tasks: radial to/from center, repetitive horizontal, nonrepetitive oblique, random (wide 2-D range), and random with pin-hole goggles. Although 2-D gaze direction (of Es) was controlled more tightly than the contributing 2-D Hs and Eh components, the torsional standard deviation of Es was greater (mean 3.55 degrees ) than Hs (3.10 degrees ), which in turn was greater than Eh (1.87 degrees ) during random fixations. Thus the 3-D Es range appeared to be the byproduct of Hs and Eh constraints, resulting in a pseudoplanar Es range that was twisted (in orthogonal coordinates) like the zero torsion range of Fick coordinates. The Hs fixation range was similarly Fick-like, whereas the Eh fixation range was quasiplanar. The latter Eh range was maintained through exquisite saccade/slow phase coordination, i.e., during each head movement, multiple anticipatory saccades drove the eye torsionally out of the planar range such that subsequent slow phases drove the eye back toward the fixation range. The Fick-like Hs constraint was maintained by the following strategies: first, during purely vertical/horizontal movements, the head rotated about constantly oriented axes that closely resembled physical Fick gimbals, i.e., about head-fixed horizontal axes and space-fixed vertical axes, respectively (although in 1 animal, the latter constraint was relaxed during repetitive horizontal movements, allowing for trajectory optimization). However, during large

  5. Moving a hand-held object: Reconstruction of referent coordinate and apparent stiffness trajectories

    PubMed Central

    Ambike, Satyajit; Zhou, Tao; Zatsiorsky, Vladimir M.; Latash, Mark L.

    2015-01-01

    This study used the framework of the referent configuration hypothesis and slow changes in the external conditions during vertical oscillation of a hand-held object to infer the characteristics of hypothetical control variables. The study had two main objectives: (1) to show that hypothetical control variables, namely, referent coordinates and apparent stiffness of vertical hand position and grip force can be measured in an experiment; and (2) to establish relation(s) between these control variables that yield the classic grip-force-load-force coupling. Healthy subjects gripped a handle and performed vertical oscillations between visual targets at one of five metronome-prescribed frequencies. A Hapticmaster robot was used to induce slow changes in the vertical force applied to the handle, while the size of the handle was changed slowly leading to changes in the grip aperture. The subjects were instructed not to react to possible changes in the external forces. A linear, second-order model was used to reconstruct the referent coordinate and apparent stiffness values for each phase of the vertical oscillation cycle using across-cycle regressions. The reconstructed time profiles of the referent coordinates and apparent stiffness showed consistent trends across subjects and movement frequencies. To validate the method, these values were used to predict the vertical force and the grip force applied to the handle for movement cycles that were not utilized in the reconstruction process. Analysis of the coupling between the four variables, two referent coordinates and two apparent stiffness values, revealed a single strong constraint reflecting the coupling between the grip force and vertical force. We view these data as providing experimental support for the idea of controlling natural, multi-muscle actions with shifts in a low-dimensional set of referent coordinates. PMID:25896800

  6. Moving a hand-held object: Reconstruction of referent coordinate and apparent stiffness trajectories.

    PubMed

    Ambike, S; Zhou, T; Zatsiorsky, V M; Latash, M L

    2015-07-01

    This study used the framework of the referent configuration hypothesis and slow changes in the external conditions during vertical oscillation of a hand-held object to infer the characteristics of hypothetical control variables. The study had two main objectives: (1) to show that hypothetical control variables, namely, referent coordinates and apparent stiffness of vertical hand position and grip force can be measured in an experiment; and (2) to establish relation(s) between these control variables that yield the classic grip-force-load-force coupling. Healthy subjects gripped a handle and performed vertical oscillations between visual targets at one of five metronome-prescribed frequencies. A HapticMaster robot was used to induce slow changes in the vertical force applied to the handle, while the size of the handle was changed slowly leading to changes in the grip aperture. The subjects were instructed not to react to possible changes in the external forces. A linear, second-order model was used to reconstruct the referent coordinate and apparent stiffness values for each phase of the vertical oscillation cycle using across-cycle regressions. The reconstructed time profiles of the referent coordinates and apparent stiffness showed consistent trends across subjects and movement frequencies. To validate the method, these values were used to predict the vertical force and the grip force applied to the handle for movement cycles that were not utilized in the reconstruction process. Analysis of the coupling between the four variables, two referent coordinates and two apparent stiffness values, revealed a single strong constraint reflecting the coupling between the grip force and vertical force. We view these data as providing experimental support for the idea of controlling natural, multi-muscle actions with shifts in a low-dimensional set of referent coordinates. PMID:25896800

  7. Deep brain stimulation of the subthalamic nucleus facilitates coordination of hand preshaping in Parkinson's disease.

    PubMed

    Schettino, L F; Van Erp, E; Hening, W; Lessig, S; Song, D; Barba, D; Poizner, H

    2009-01-01

    Several studies have found that Parkinson's disease (PD) disrupts the organization of complex motor sequences regardless of the influence of parkinsonian medications. A clear candidate for the neural bases of such deficits, which we term "coordinative," is the failure to integrate propioceptive and visual information by cortico-striatal circuits in a timed fashion. Recent reports, however, have indicated that deep-brain stimulation of the subthalamic nucleus (STN DBS) may result in an improvement in coordinative deficits beyond the amelioration of "intensive deficits" such as bradykinesia and scaling errors. The present study examined the spatio-temporal organization underlying the shaping of the hand during reaching to grasp objects differing in shape. Six PD patients ON and OFF their STN DBS when OFF their concomitant medications and six age-matched controls participated in this study. STN DBS improved the coordination involved in preshaping the hand while grasping. We discuss these results in light of our earlier work with PD patients on and off dopamine replacement therapy. PMID:19922392

  8. Effect of terminal accuracy requirements on temporal gaze-hand coordination during fast discrete and reciprocal pointings

    PubMed Central

    2011-01-01

    Background Rapid discrete goal-directed movements are characterized by a well known coordination pattern between the gaze and the hand displacements. The gaze always starts prior to the hand movement and reaches the target before hand velocity peak. Surprisingly, the effect of the target size on the temporal gaze-hand coordination has not been directly investigated. Moreover, goal-directed movements are often produced in a reciprocal rather than in a discrete manner. The objectives of this work were to assess the effect of the target size on temporal gaze-hand coordination during fast 1) discrete and 2) reciprocal pointings. Methods Subjects performed fast discrete (experiment 1) and reciprocal (experiment 2) pointings with an amplitude of 50 cm and four target diameters (7.6, 3.8, 1.9 and 0.95 cm) leading to indexes of difficulty (ID = log2[2A/D]) of 3.7, 4.7, 5.7 and 6.7 bits. Gaze and hand displacements were synchronously recorded. Temporal gaze-hand coordination parameters were compared between experiments (discrete and reciprocal pointings) and IDs using analyses of variance (ANOVAs). Results Data showed that the magnitude of the gaze-hand lead pattern was much higher for discrete than for reciprocal pointings. Moreover, while it was constant for discrete pointings, it decreased systematically with an increasing ID for reciprocal pointings because of the longer duration of gaze anchoring on target. Conclusion Overall, the temporal gaze-hand coordination analysis revealed that even for high IDs, fast reciprocal pointings could not be considered as a concatenation of discrete units. Moreover, our data clearly illustrate the smooth adaptation of temporal gaze-hand coordination to terminal accuracy requirements during fast reciprocal pointings. It will be interesting for further researches to investigate if the methodology used in the experiment 2 allows assessing the effect of sensori-motor deficits on gaze-hand coordination. PMID:21320315

  9. "Alien hand" and loss of bimanual coordination after dominant anterior cerebral artery territory infarction.

    PubMed Central

    McNabb, A W; Carroll, W M; Mastaglia, F L

    1988-01-01

    Three patients with dominant anterior cerebral artery territory infarction demonstrated a severe disturbance of upper limb motor control with impaired bimanual coordination, the "alien hand" sign, and intermanual conflict, in addition to signs of callosal interruption and a transcortical motor aphasia. Recordings of movement-related potentials in one patient showed an attenuated Bereitschaftspotential and a greater asymmetry of the NS' component of the premotor negativity with left finger than with right finger movement. The impairment of bimanual motor control and associated abnormal motor behaviour of the right hand in these cases are postulated to be due to involvement of the supplementary motor area and related areas of the medial frontal cortex. Images PMID:3346686

  10. Hand-Arm Coordinated Manipulation Using Active Body-Environment Contact

    NASA Astrophysics Data System (ADS)

    Sugaiwa, Taisuke; Iwata, Hiroyasu; Sugano, Shigeki

    Human-symbiotic humanoid robots that can perform tasks dexterously with their hands are needed in our homes, welfare facilities, and other places. To improve their performance of tasks, we propose a scheme of controlling motion aimed at appropriately coordinated hand and arm motions. By observing human manual tasks, we identify an active body-environment contact as a kind of human manual skills and devise a motion control scheme based on it. We also analyze the effectiveness of the combination of the active body-environment contact and our proposed scheme in example tasks of the adding/removing constraint task. We validate our motion control scheme through actual tests on a prototype human-symbiotic humanoid robot.

  11. Long-Latency Feedback Coordinates Upper-Limb and Hand Muscles during Object Manipulation Tasks123

    PubMed Central

    Thonnard, Jean-Louis; Scott, Stephen H.

    2016-01-01

    Suppose that someone bumps into your arm at a party while you are holding a glass of wine. Motion of the disturbed arm will engage rapid and goal-directed feedback responses in the upper-limb. Although such responses can rapidly counter the perturbation, it is also clearly desirable not to destabilize your grasp and/or spill the wine. Here we investigated how healthy humans maintain a stable grasp following perturbations by using a paradigm that requires spatial tuning of the motor response dependent on the location of a virtual target. Our results highlight a synchronized expression of target-directed feedback in shoulder and hand muscles occurring at ∼60 ms. Considering that conduction delays are longer for the more distal hand muscles, these results suggest that target-directed responses in hand muscles were initiated before those for the shoulder muscles. These results show that long-latency feedback can coordinate upper limb and hand muscles during object manipulation tasks. PMID:27022624

  12. Pilot Study: The Role of the Hemispheric Lateralization in Mental Disorders by Use of the Limb (Eye, Hand, Foot) Dominance

    PubMed Central

    Goodarzi, Naser; Dabbaghi, Parviz; Valipour, Habib; Vafadari, Behnam

    2015-01-01

    Introduction: Based on the previous studies, we know that the hemispheric lateralization defects, increase the probability of psychological disorders. We also know that dominant limb is controlled by dominant hemisphere and limb preference is used as an indicator for hemisphere dominance. In this study we attempted to explore the hemispheric dominance by the use of three limbs (hand, foot and eye). Methods: We performed this survey on two samples, psychiatric patients compared with normal population. For this purpose, knowing that the organ dominance is stabilized in adolescence, and age has no effect on the people above 15, we used 48 high school girls and 65 boys as the final samples of normal population. The patient group included 57 male and 26 female who were chronic psychiatric patients. Results: The result shows that left-eye dominance is more in patients than the normal group (P=0.000) but the handedness and footedness differences are not significance. In psychotic, bipolar and depressive disorders, eye dominance had significant difference (P=0.018). But this is not true about hand and foot dominance. Discussion: Our findings proved that generally in psychiatric patients, left-eye dominance is more common, left-eye dominance is also more in psychotic and depressive disorders. It is less common in bipolar disorders. PMID:27307954

  13. Hand Washing Induces a Clean Slate Effect in Moral Judgments: A Pupillometry and Eye-Tracking Study

    PubMed Central

    Kaspar, Kai; Krapp, Vanessa; König, Peter

    2015-01-01

    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. PMID:25994083

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

    PubMed

    Kaspar, Kai; Krapp, Vanessa; König, Peter

    2015-01-01

    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. PMID:25994083

  15. Gaze Behavior in One-Handed Catching and Its Relation with Interceptive Performance: What the Eyes Can't Tell

    PubMed Central

    Cesqui, Benedetta; Mezzetti, Maura; Lacquaniti, Francesco; d'Avella, Andrea

    2015-01-01

    In ball sports, it is usually acknowledged that expert athletes track the ball more accurately than novices. However, there is also evidence that keeping the eyes on the ball is not always necessary for interception. Here we aimed at gaining new insights on the extent to which ocular pursuit performance is related to catching performance. To this end, we analyzed eye and head movements of nine subjects catching a ball projected by an actuated launching apparatus. Four different ball flight durations and two different ball arrival heights were tested and the quality of ocular pursuit was characterized by means of several timing and accuracy parameters. Catching performance differed across subjects and depended on ball flight characteristics. All subjects showed a similar sequence of eye movement events and a similar modulation of the timing of these events in relation to the characteristics of the ball trajectory. On a trial-by-trial basis there was a significant relationship only between pursuit duration and catching performance, confirming that keeping the eyes on the ball longer increases catching success probability. Ocular pursuit parameters values and their dependence on flight conditions as well as the eye and head contributions to gaze shift differed across subjects. However, the observed average individual ocular behavior and the eye-head coordination patterns were not directly related to the individual catching performance. These results suggest that several oculomotor strategies may be used to gather information on ball motion, and that factors unrelated to eye movements may underlie the observed differences in interceptive performance. PMID:25793989

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

    SciTech Connect

    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. Review and Evaluation of Hand–Arm Coordinate Systems for Measuring Vibration Exposure, Biodynamic Responses, and Hand Forces

    PubMed Central

    Dong, Ren G.; Sinsel, Erik W.; Welcome, Daniel E.; Warren, Christopher; Xu, Xueyan S.; McDowell, Thomas W.; Wu, John Z.

    2015-01-01

    The hand coordinate systems for measuring vibration exposures and biodynamic responses have been standardized, but they are not actually used in many studies. This contradicts the purpose of the standardization. The objectives of this study were to identify the major sources of this problem, and to help define or identify better coordinate systems for the standardization. This study systematically reviewed the principles and definition methods, and evaluated typical hand coordinate systems. This study confirms that, as accelerometers remain the major technology for vibration measurement, it is reasonable to standardize two types of coordinate systems: a tool-based basicentric (BC) system and an anatomically based biodynamic (BD) system. However, these coordinate systems are not well defined in the current standard. Definition of the standard BC system is confusing, and it can be interpreted differently; as a result, it has been inconsistently applied in various standards and studies. The standard hand BD system is defined using the orientation of the third metacarpal bone. It is neither convenient nor defined based on important biological or biodynamic features. This explains why it is rarely used in practice. To resolve these inconsistencies and deficiencies, we proposed a revised method for defining the realistic handle BC system and an alternative method for defining the hand BD system. A fingertip-based BD system for measuring the principal grip force is also proposed based on an important feature of the grip force confirmed in this study. PMID:26929824

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

    PubMed

    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. PMID:25714565

  19. What the hand can't tell the eye: illusion of space constancy during accurate pointing.

    PubMed

    Chua, Romeo; Enns, James T

    2005-03-01

    When we press an elevator button or pick up a coffee cup, different visual information is used to guide our reach and to form our conscious experience of these objects. But can the information guiding our hand be brought into awareness? The fact that we can see and feel our own hand in action suggests that it might be possible. However, the dual visual systems theory claims that on-line control of movement is governed by the dorsal stream of visual processing, which is largely unconscious. Two experiments are presented as strong tests of the hypothesis that the visual information guiding on-line pointing in healthy human adults is inaccessible for conscious report. Results show that participants are incapable of consciously accessing the information used in pointing, even though they can see and feel their hands in action and accurate performance depends on it. PMID:15551080

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

    PubMed Central

    Barry, Michael P.; Dagnelie, Gislin

    2016-01-01

    multivariate analysis of variance (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. PMID:27199689

  1. Early Stages of Zebrafish Eye Formation Require the Coordinated Activity of Wnt11, Fz5, and the Wnt/β-Catenin Pathway

    PubMed Central

    Cavodeassi, Florencia; Carreira-Barbosa, Filipa; Young, Rodrigo M.; Concha, Miguel L.; Allende, Miguel L.; Houart, Corinne; Tada, Masazumi; Wilson, Stephen W.

    2009-01-01

    Summary During regional patterning of the anterior neural plate, a medially positioned domain of cells is specified to adopt retinal identity. These eye field cells remain coherent as they undergo morphogenetic events distinct from other prospective forebrain domains. We show that two branches of the Wnt signaling pathway coordinate cell fate determination with cell behavior during eye field formation. Wnt/β-catenin signaling antagonizes eye specification through the activity of Wnt8b and Fz8a. In contrast, Wnt11 and Fz5 promote eye field development, at least in part, through local antagonism of Wnt/β-catenin signaling. Additionally, Wnt11 regulates the behavior of eye field cells, promoting their cohesion. Together, these results allow us to postulate a model in which Wnt11 and Fz5 signaling promotes early eye development through the coordinated antagonism of signals that suppress retinal identity and promotion of coherence of eye field cells. PMID:15996547

  2. Carrying a rifle with both hands affects upper body transverse plane kinematics and pelvis-trunk coordination.

    PubMed

    Seay, Joseph F; Hasselquist, Leif; Bensel, Carolyn K

    2011-02-01

    The purpose of this study was to assess how carrying a rifle in both hands affects upper body motion and coordination during locomotion. In total, 11 male soldiers walked (1.34 m/s) and ran (2.46 m/s) with a weapon (M4 condition) and without a weapon (NW condition) while kinematic pelvis and trunk data were collected. Two-way ANOVA was used to compare segmental ranges of motion (ROM), pelvis-trunk coordination (continuous relative phase) and coordination variability between gait mode and weapon combinations. Carrying a weapon decreased sagittal plane trunk ROM at both speeds and increased trunk rotation during running. Mean (±SD) transverse plane coordination was more in-phase while carrying a weapon (M4 = 83°±31, NW = 60°±36, p = 0.027) and transverse plane coordination variability decreased (M4 = 23°±3.6, NW = 15°±4.4, p = 0.043). Coordination differences between M4 and NW were similar to differences reported in the literature between individuals with and without back pain. Long-term injury implications due to decreased coordination variability are discussed. STATEMENT OF RELEVANCE: Knowledge of the effects of rifle carriage on pelvis-trunk coordination may provide insight into short-term protective strategies and long-term injury mechanisms. These should be considered in occupations requiring individuals to carry torso loads in combination with holding an object in both hands that restricts arm swing. PMID:21294016

  3. Movement Coordination in Psychotherapy: Synchrony of Hand Movements is Associated with Session Outcome. A Single-Case Study.

    PubMed

    Ramseyer, Fabian; Tschacher, Wolfgang

    2016-04-01

    Previous work has shown that nonverbal behavior was associated with both session-level outcome and global outcome in psychotherapy. Nonverbal synchrony - here the coordination between patient's and psychotherapist's movement behavior - is a facet of nonverbal behavior that has recently been studied with video-based motion energy analysis (MEA). The present study aimed to replicate and extend these findings by using direct acquisition of movement data. In a single-case analysis, we monitored patient's and therapist's hand movements with a high-resolution accelerometric measurement system (Vitaport (r)). In addition to these behavioral data, both patient and therapist provided session-level ratings of various factors relevant to the psychotherapy process, which were assessed with post-session questionnaires. The patient-therapist coordination of hand movements, i.e. nonverbal synchrony, in (N = 27) sessions of this dyadic psychotherapy was positively associated with progress reported in post-session questionnaires. Sessions with good evaluations concerning the quality of therapeutic alliance were characterized by high movement coordination. Thus, accelerometric data of this therapy dyad confirmed previous findings gained through video analyses: The coordination of nonverbal behavior shown by patient and therapist was an indicator of beneficial processes occurring within sessions. This replication study showed that nonverbal synchrony embodies important aspects of the alliance. Its assessment and quantification may provide therapists important additional information on processes that usually occur outside conscious awareness, but that nevertheless influence core aspects of the therapy. PMID:27033131

  4. Control Model for Dampening Hand Vibrations Using Information of Internal and External Coordinates

    PubMed Central

    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. PMID:25876037

  5. Head-Eye Coordination Increases with Age and Varies across Countries

    PubMed Central

    Poirier, Frédéric J.A.M.; Giraudet, Guillaume; Faubert, Jocelyn

    2015-01-01

    ABSTRACT Purpose Head movements in older people may contribute to their dizziness and equilibrium problems. Head gain is the ratio of head movement to total movement (head + eye) when executing a saccade to an eccentric target. Two studies have investigated the relationship between head gain and age but have provided conflicting results. Methods We report head gain data collected from research laboratories and optician stores. Our sample sizes are much larger (n = 657 for laboratory, n = 64,458 for optician stores), permitting more detailed analyses. Results The head-eye coefficient, expressed as 100 times the square root of head gain, was bimodal with one mode of primarily eye movers and one mode of eye-and-head movers. Head-eye coefficient increased with age and was invariant with eye correction and gender. We also found an effect of nation that seemed associated with gross domestic product or by latitude (in the northern hemisphere) and log population density. Discussion Assuming that head movements and visual distortions contribute to dizziness and equilibrium problems, our study suggests that customizing eyewear based on age and country may help in reducing the prevalence of problems associated with head and/or eye movements. PMID:26421683

  6. Auditory signals evolve from hybrid- to eye-centered coordinates in the primate superior colliculus.

    PubMed

    Lee, Jungah; Groh, Jennifer M

    2012-07-01

    Visual and auditory spatial signals initially arise in different reference frames. It has been postulated that auditory signals are translated from a head-centered to an eye-centered frame of reference compatible with the visual spatial maps, but, to date, only various forms of hybrid reference frames for sound have been identified. Here, we show that the auditory representation of space in the superior colliculus involves a hybrid reference frame immediately after the sound onset but evolves to become predominantly eye centered, and more similar to the visual representation, by the time of a saccade to that sound. Specifically, during the first 500 ms after the sound onset, auditory response patterns (N = 103) were usually neither head nor eye centered: 64% of neurons showed such a hybrid pattern, whereas 29% were more eye centered and 8% were more head centered. This differed from the pattern observed for visual targets (N = 156): 86% were eye centered, <1% were head centered, and only 13% exhibited a hybrid of both reference frames. For auditory-evoked activity observed within 20 ms of the saccade (N = 154), the proportion of eye-centered response patterns increased to 69%, whereas the hybrid and head-centered response patterns dropped to 30% and <1%, respectively. This pattern approached, although did not quite reach, that observed for saccade-related activity for visual targets: 89% were eye centered, 11% were hybrid, and <1% were head centered (N = 162). The plainly eye-centered visual response patterns and predominantly eye-centered auditory motor response patterns lie in marked contrast to our previous study of the intraparietal cortex, where both visual and auditory sensory and motor-related activity used a predominantly hybrid reference frame (Mullette-Gillman et al. 2005, 2009). Our present findings indicate that auditory signals are ultimately translated into a reference frame roughly similar to that used for vision, but suggest that such signals might

  7. Visuomotor processing and hand force coordination in dyslexic children during a visually guided manipulation task.

    PubMed

    de Freitas, Paulo B; Pedão, Sabrina T; Barela, Jose A

    2014-10-01

    Developmental Dyslexia negatively affects children's reading and writing ability and, in most cases, performance in sensorimotor tasks. These deficits have been associated with structural and functional alterations in the cerebellum and the posterior parietal cortex (PPC). Both neural structures are active during visually guided force control and in the coordination of load force (LF) and grip force (GF) during manipulation tasks. Surprisingly, both phenomena have not been investigated in dyslexic children. Therefore, the aim of this study was to compare dyslexic and non-dyslexic children regarding their visuomotor processing ability and GF-LF coordination during a static manipulation task. Thirteen dyslexic (8-14 YO) and 13 age- and sex-matched non-dyslexic (control) children participated in the study. They were asked to grasp a fixed instrumented handle using the tip of all digits and pull the handle upward exerting isometric force to match a ramp-and-hold force profile displayed in a computer monitor. Task performance (i.e., visuomotor coordination) was assessed by RMSE calculated in both ramp and hold phases. GF-LF coordination was assessed by the ratio between GF and LF (GF/LF) calculated at both phases and the maximum value of a cross-correlation function (rmax) and its respective time lag calculated at ramp phase. The results revealed that the RMSE at both phases was larger in dyslexic than in control children. However, we found that GF/LF, rmax, and time lags were similar between groups. Those findings indicate that dyslexic children have a mild deficit in visuomotor processing but preserved GF-LF coordination. Altogether, these findings suggested that dyslexic children could present mild structural and functional alterations in specific PPC or cerebellum areas that are directly related to visuomotor processing. PMID:24960554

  8. The Effects of Hunger on Hand-Mouth Coordination in Newborn Infants.

    ERIC Educational Resources Information Center

    Lew, Adina R.; Butterworth, George

    1995-01-01

    Examined the effects of hunger on the hand-mouth (HM) behavior of a group of newborn infants. Found that significantly more mouth opening before contacts to the mouth than those to the face occurred before but not after feeding, suggesting some link between HM behavior and hunger state. (MDM)

  9. Effects of Repetitive Transcranial Magnetic Stimulation in Performing Eye-Hand Integration Tasks: Four Preliminary Studies with Children Showing Low-Functioning Autism

    ERIC Educational Resources Information Center

    Panerai, Simonetta; Tasca, Domenica; Lanuzza, Bartolo; Trubia, Grazia; Ferri, Raffaele; Musso, Sabrina; Alagona, Giovanna; Di Guardo, Giuseppe; Barone, Concetta; Gaglione, Maria P.; Elia, Maurizio

    2014-01-01

    This report, based on four studies with children with low-functioning autism, aimed at evaluating the effects of repetitive transcranial magnetic stimulation delivered on the left and right premotor cortices on eye-hand integration tasks; defining the long-lasting effects of high-frequency repetitive transcranial magnetic stimulation; and…

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

    ERIC Educational Resources Information Center

    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…

  11. The Coordinated Interplay of Scene, Utterance, and World Knowledge: Evidence from Eye Tracking

    ERIC Educational Resources Information Center

    Knoeferle, Pia; Crocker, Matthew W.

    2006-01-01

    Two studies investigated the interaction between utterance and scene processing by monitoring eye movements in agent-action-patient events, while participants listened to related utterances. The aim of Experiment 1 was to determine if and when depicted events are used for thematic role assignment and structural disambiguation of temporarily…

  12. Can discrete joint action be synergistic? Studying the stabilization of interpersonal hand coordination.

    PubMed

    Romero, Veronica; Kallen, Rachel; Riley, Michael A; Richardson, Michael J

    2015-10-01

    The human perceptual-motor system is tightly coupled to the physical and informational dynamics of a task environment. These dynamics operate to constrain the high-dimensional order of the human movement system into low-dimensional, task-specific synergies-functional groupings of structural elements that are temporarily constrained to act as a single coordinated unit. The aim of the current study was to determine whether synergistic processes operate when coacting individuals coordinate to perform a discrete joint-action task. Pairs of participants sat next to each other and each used 1 arm to complete a pointer-to-target task. Using the uncontrolled manifold (UCM) analysis for the first time in a discrete joint action, the structure of joint-angle variance was examined to determine whether there was synergistic organization of the degrees of freedom employed at the interpersonal or intrapersonal levels. The results revealed that the motor actions performed by coactors were synergistically organized at both the interpersonal and intrapersonal levels. More importantly, however, the interpersonal synergy was found to be significantly stronger than the intrapersonal synergies. Accordingly, the results provide clear evidence that coacting individuals can become temporarily organized to form single synergistic 2-person systems during performance of a discrete joint action. PMID:26052696

  13. Can Discrete Joint Action Be Synergistic? Studying the Stabilization of Interpersonal Hand Coordination

    PubMed Central

    Romero, Veronica; Kallen, Rachel; Riley, Michael A.; Richardson, Michael J.

    2016-01-01

    The human perceptual-motor system is tightly coupled to the physical and informational dynamics of a task environment. These dynamics operate to constrain the high-dimensional order of the human movement system into low-dimensional, task-specific synergies—functional groupings of structural elements that are temporarily constrained to act as a single coordinated unit. The aim of the current study was to determine whether synergistic processes operate when coacting individuals coordinate to perform a discrete joint-action task. Pairs of participants sat next to each other and each used 1 arm to complete a pointer-to-target task. Using the uncontrolled manifold (UCM) analysis for the first time in a discrete joint action, the structure of joint-angle variance was examined to determine whether there was synergistic organization of the degrees of freedom employed at the interpersonal or intrapersonal levels. The results revealed that the motor actions performed by coactors were synergistically organized at both the interpersonal and intrapersonal levels. More importantly, however, the interpersonal synergy was found to be significantly stronger than the intrapersonal synergies. Accordingly, the results provide clear evidence that coacting individuals can become temporarily organized to form single synergistic 2-person systems during performance of a discrete joint action. PMID:26052696

  14. Predictable Vertical Targets Acquisition - The Eye-Head Coordination and the Triggering Effect

    NASA Technical Reports Server (NTRS)

    Kolev, Ognyan I.; Reschke, Millard F.

    2016-01-01

    The current study was designed to investigate target acquisition in the vertical plane with emphasis on establishing strategy differences associated with acquisition triggering methods. Eight subjects were tested. Measurements consisted of target acquisition time, eye-head latency differences, velocity of gaze, eyes and head, and head amplitude. Using three-way repeated measures ANOVA the results show that the strategy for acquisition of predictable visual targets in vertical plane with the head unrestrained significantly depended on: (i) the direction of the gaze motion with respect to the gravity vector (i.e. there is significant up-down asymmetry); (ii) the angular distance of the target and (iii) the method of triggering the command to acquire the target - external versus internal. The data also show that when vertical acquisition is compared with triggering methods in the horizontal plane there is a difference in overall strategy for the acquisition of targets with the same spatial distances from straight ahead gaze when both the eyes and head are used. Among the factors contributing to the difference in strategy for vertical target acquisition are: the gravitational vector, the relationship of target displacement and vestibular activation, biomechanical and neural control, asymmetries and the difference in the vertical field of view.

  15. Eye muscle repair - series (image)

    MedlinePlus

    ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ... The extraocular muscles of the eye (external to the eyeball) control the positioning of the eyes. They coordinate of the eye ...

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

    PubMed

    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. PMID:25885446

  17. Dual Logic and Cerebral Coordinates for Reciprocal Interaction in Eye Contact

    PubMed Central

    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. PMID:25885446

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

    PubMed Central

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

    2014-01-01

    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

  19. Manual tracking enhances smooth pursuit eye movements

    PubMed Central

    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. PMID:26605840

  20. Motor imagery is less efficient in adults with probable developmental coordination disorder: evidence from the hand rotation task.

    PubMed

    Hyde, Christian; Fuelscher, Ian; Buckthought, Karen; Enticott, Peter G; Gitay, Maria A; Williams, Jacqueline

    2014-11-01

    The present study aimed to provide preliminary insight into the integrity of motor imagery (MI) in adults with probable developmental coordination disorder (pDCD). Based on a strong body of evidence indicating that paediatric samples of DCD often experience difficulties engaging MI, we hypothesised that young adults with pDCD would demonstrate similar difficulties. The performance of 12 young adults (19-35 years) with pDCD was compared to 47 age-matched controls on a traditional mental hand rotation task. Mean inverse efficiency scores were generated for each participant by dividing each participant's mean RT by their proportion of correct responses at each of the stimuli presentation conditions. Preliminary analysis revealed that the performance profiles of individuals with pDCD and age-matched controls showed evidence of being constrained by the biomechanical and postural constraints of real movement, suggesting that both groups engaged in an embodied (MI) strategy to complete the task. Despite engaging in a MI strategy, however, young adults with pDCD were nonetheless significantly less efficient when doing so, shown by significant main effects for group on all group efficiency comparisons. Based on the assumption that MI provides insight into the internal 'neural' action representation that precedes action, we argue that the less efficient MI performance demonstrated by young adults with pDCD may indicate inefficiencies engaging or implementing internal action representations. Implications and directions for future research are discussed. PMID:25134075

  1. Black Eye

    MedlinePlus

    ... Aug 30, 2016 Toddlers Most at Risk of Chemical Burns to Eyes Aug 26, 2016 Firework Blinds Teenager, Severs Hand Jun 29, ... at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For ...

  2. Outcome measures for hand function naturally reveal three latent domains in older adults: strength, coordinated upper extremity function, and sensorimotor processing

    PubMed Central

    Lawrence, Emily L.; Dayanidhi, Sudarshan; Fassola, Isabella; Requejo, Philip; Leclercq, Caroline; Winstein, Carolee J.; Valero-Cuevas, Francisco J.

    2015-01-01

    Understanding the mapping between individual outcome measures and the latent functional domains of interest is critical to a quantitative evaluation and rehabilitation of hand function. We examined whether and how the associations among six hand-specific outcome measures reveal latent functional domains in elderly individuals. We asked 66 healthy older adult participants (38F, 28M, 66.1 ± 11.6 years, range: 45–88 years) and 33 older adults (65.8 ± 9.7 years, 44–81 years, 51 hands) diagnosed with osteoarthritis (OA) of the carpometacarpal (CMC) joint, to complete six functional assessments: hand strength (Grip, Key and Precision Pinch), Box and Block, Nine Hole Pegboard, and Strength-Dexterity tests. The first three principal components suffice to explain 86% of variance among the six outcome measures in healthy older adults, and 84% of variance in older adults with CMC OA. The composition of these dominant associations revealed three distinct latent functional domains: strength, coordinated upper extremity function, and sensorimotor processing. Furthermore, in participants with thumb CMC OA we found a blurring of the associations between the latent functional domains of strength and coordinated upper extremity function. This motivates future work to understand how the physiological effects of thumb CMC OA lead upper extremity coordination to become strongly associated with strength, while dynamic sensorimotor ability remains an independent functional domain. Thus, when assessing the level of hand function in our growing older adult populations, it is particularly important to acknowledge its multidimensional nature—and explicitly consider how each outcome measure maps to these three latent and fundamental domains of function. Moreover, this ability to distinguish among latent functional domains may facilitate the design of treatment modalities to target the rehabilitation of each of them. PMID:26097455

  3. From hand to eye: the role of literacy, familiarity, graspability, and vision-for-action on enantiomorphy.

    PubMed

    Fernandes, Tânia; Kolinsky, Régine

    2013-01-01

    Literacy in a script with mirrored symbols boosts the ability to discriminate mirror images, i.e., enantiomorphy. In the present study we evaluated the impact of four factors on enantiomorphic abilities: (i) the degree of literacy of the participants; (ii) the familiarity of the material; (iii) the strength of the association between familiar objects and manipulation, i.e., graspability; and (iv) the involvement of vision-for-action in the task. Three groups of adults - unschooled illiterates, unschooled ex-illiterates, and schooled literates - participated in two experiments. In Experiment 1, participants performed a vision-for-perception task, i.e., an orientation-based same-different comparison task, on pictures of familiar objects and geometric shapes. Graspability of familiar objects and unfamiliarity of the stimuli facilitated orientation discrimination, but did not help illiterate participants to overcome their difficulties with enantiomorphy. Compared to a baseline, illiterate adults had the strongest performance drop for mirror images, whereas for plane rotations the performance drop was similar across groups. In Experiment 2, participants performed a vision-for-action task; they were asked to decide which hand they would use to grasp a familiar object according to its current position (e.g., indicating left-hand usage to grasp a cup with the handle on the left side, and right-hand usage for its mirror image). Illiterates were as skillful as literates to perform this task. The present study thus provided three important findings. First, once triggered by literacy, enantiomorphy generalizes to any visual object category, as part of vision-for-perception, i.e., in visual recognition and identification processes. Second, the impact of literacy is much stronger on enantiomorphy than on the processing of other orientation contrasts. Third, in vision-for-action tasks, illiterates are as sensitive as literates to enantiomorphic-related information. PMID:23232335

  4. Optimum ratio of upper to lower limb lengths in hand-carrying of a load under the assumption of frequency coordination.

    PubMed

    Wang, W J; Crompton, R H; Li, Y; Gunther, M M

    2003-02-01

    The ratio of the upper to lower limb lengths [or the intermembral index (IMI)] in the earliest human ancestors is closer to that of the living chimpanzees than to our own, although the former show undoubted adaptations to bipedality. What biomechanical factors could then have led to the phenomenon of genus Homo? This paper proposes and evaluates a relationship between IMI and hand-carrying. Assuming that coordination of limb swing frequencies of the upper and lower limbs would be the subject of positive selection, a mathematical expression was derived and can in part explain the changes in IMI. We found that AL-288-1 [3.6 million years old (MY)], the most complete skeleton of the early hominid Australopithecus afarensis, could only have carried loads equivalent to 15-50% of the upper limb weight while maintaining swing symmetry, but KNM WT-15000, Homo ergaster (1.8MY) and modern humans could both carry loads 3 times heavier than the upper limb while maintaining swing symmetry. The carrying ability of chimpanzees would be inferior to that of AL-288-1. The IMI of modern humans, at 68-70, is the smallest, and is optimal for hand-carrying under our criteria. Under reduced selection pressure for hand-carrying, but unreduced selection for mechanical effectiveness, we might expect humans to evolve a longer upper limb, to improve swing symmetry when unloaded. PMID:12547362

  5. Successes and Difficulties in the Individual Inclusion of Children with Autism Spectrum Disorder (ASD) in the Eyes of Their Coordinators

    ERIC Educational Resources Information Center

    Eldar, Eitan; Talmor, Rachel; Wolf-Zukerman, Tali

    2010-01-01

    This study examined the inclusion of children with Autism Spectrum Disorder (ASD) in regular classes and analysed the factors related to its success and failure. Thirty-seven inclusion coordinators participated in the study and conveyed their view about their own experience. The qualitative methodology used in this study was comprised of regular…

  6. Dry eye syndrome

    MedlinePlus

    ... of dry eyes include: Dry environment or workplace (wind, air conditioning) Sun exposure Smoking or second-hand ... NOT smoke and avoid second-hand smoke, direct wind, and air conditioning. Use a humidifier, especially in ...

  7. Synthesis, structure, and electrochemistry and magnetic properties of a novel 1D homochiral MnIII(5-Brsalen) coordination polymer with left-handed helical character

    NASA Astrophysics Data System (ADS)

    Dong, Dapeng; Yu, Naisen; Zhao, Haiyan; Liu, Dedi; Liu, Jia; Li, Zhenghua; Liu, Dongping

    2016-01-01

    A novel homochiral manganese (III) Mn(5-Brsalen) coordination polymer with left-handed helical character by spontaneous resolution on crystallization by using Mn(5-Brsalen) and 4,4-bipyridine, [MnIII(5-Brsalen)(4,4-bipy)]·ClO4·CH3OH (1) (4,4-bipy = 4,4-bipyridine) has been synthesized and structurally characterized by X-ray single-crystal diffraction, elemental analysis and infrared spectroscopy. In compound 1, each manganese(III) anion is six-coordinate octahedral being bonded to four atoms of 5-Brsalen ligand in an equatorial plane and two nitrogen atoms from a 4,4-bipyridine ligand in axial positions. The structure of compound 1 can be described a supramolecular 2D-like structure which was formed by the intermolecular π-stacking interactions between the neighboring chains of the aromatic rings of 4,4-bipyridine and 5-Brsalen molecules. UV-vis absorption spectrum, electrochemistry and magnetic properties of the compound 1 have also been studied.

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

    PubMed

    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. PMID

  9. Smoking and Eye Health

    MedlinePlus

    ... Eye Health Apr. 14, 2014 Avoiding smoking and second hand smoke — or quitting if you are a smoker — are ... influence your eyes’ health. And tobacco smoke, including second-hand smoke, is an irritant that worsens dry eye , a ...

  10. Eye Movements of Flatfish for Different Gravity Condition

    NASA Astrophysics Data System (ADS)

    Iwata, Kaori; Takabayashi, Akira; Imada, Hideki; Miyachi, Ei-Ichi

    On Earth, gravity sensation plays a basic role for all of physiological phenomena in every creature. In microgravity, loss of gravity input causes many functional disorders in animals and humans. During adaptation to microgravity, otolith-mediated response such as eye movements would alter. Flatfish provide a natural model for the study of adaptive changes in the vestibuloocular reflex. During metamorphosis, vestibular and oculomotor coordinate of flatfish displaced 90 degrees about the longitudinal body axis. Therefore, it is expected that microgravity induce the sensory mismatch in adult flatfish. In this study, we analyzed the eye movements of normal and otolith removed flatfish for body tilting and the eye movements of normal flatfish during microgravity produced by parabolic aircraft flight. The fish was fixed on the tilting table controlled by computer. The eye movements for body tilting along the different body axis were video-recorded. The vertical and torsional eye rotations were analyzed frame by frame. In normal flatfish, torsional eye movements were larger for head up or head down tilting than leftward or rightward tilting. On the other hand, vertical eye movements were larger for leftward or rightward tilting than head up or head down tilting. After removal of left side utlicular otolith, the vertical eye movement for 180 degrees body tilting disappeared. For the changes of gravity, vertical eye movements were observed. These results suggested that eye movements of flatfish adapted to Earth's gravity condition and sacculus and lagena might play important role for otolith-ocular eye movements.

  11. Eye Infections

    MedlinePlus

    Your eyes can get infections from bacteria, fungi, or viruses. Eye infections can occur in different parts of the eye and can affect just one eye or both. Two common eye infections are Conjunctivitis - also known as pinkeye. Conjunctivitis is ...

  12. An Eye for Learning.

    ERIC Educational Resources Information Center

    Ostwald, Thomas

    1995-01-01

    Presents a hands-on activity as an excellent starting point for investigations related to the eye. Involves making a simple model of the vertebrate eye to illustrate the formation of an upside-down image on the retina by the lens. Links to investigations in numerous science disciplines including astronomy, genetics, biology, earth science, and…

  13. Design and evaluation of a computerized test for hand motor skills.

    PubMed

    Hsiao, Hsien-Sheng; Chang, Cheng-Sian; Lin, Chien-Yu; Chiu, Ching-Tsun

    2014-06-01

    The purposes of this study are to design and develop a computerized test to measure junior high school students' motor skills, specifically their abilities in hand-eye motor coordination and hand motor skills, using the Wii Remote. The hand motor skills computerized test, which is based on the operational examinations in the General Aptitude Test Battery, examines hand and finger dexterity (i.e., motion, rotation, fabrication, and disassembly tests). 55 students participated in the experiment to assess the reliability and validity of the computerized test, which were supported. Information literacy and experience in the use of Wii devices did not affect the reliability. PMID:25068744

  14. 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

    ERIC Educational Resources Information Center

    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.…

  15. Eye redness

    MedlinePlus

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

  16. Eye Cancer

    MedlinePlus

    ... Eye Cancer - Overview Request Permissions Print to PDF Eye Cancer - Overview Approved by the Cancer.Net Editorial Board , ... Cancer Research and Advocacy Survivorship Blog About Us Eye Cancer Guide Cancer.Net Guide Eye Cancer Overview Statistics ...

  17. Eye emergencies

    MedlinePlus

    ... Trauma A black eye is usually caused by direct trauma to the eye or face. The bruise ... can cause bruising around the eyes, even without direct injury to the eye. Sometimes, serious damage to ...

  18. Eye pain

    MedlinePlus

    Ophthalmalgia; Pain - eye ... Pain in the eye can be an important symptom of a health problem. Make sure you tell your health care provider if you have eye pain that does not go away. Tired eyes or ...

  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

    PubMed Central

    Meguerditchian, Adrien; Phillips, Kimberley A.; Chapelain, Amandine; Mahovetz, Lindsay M.; Milne, Scott; Stoinski, Tara; Bania, Amanda; Lonsdorf, Elizabeth; Schaeffer, Jennifer; Russell, Jamie; Hopkins, William D.

    2015-01-01

    A number of factors have been proposed to influence within and between species variation in handedness in non-human 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 four 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. PMID:26635693

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

    PubMed

    Meguerditchian, Adrien; Phillips, Kimberley A; Chapelain, Amandine; Mahovetz, Lindsay M; Milne, Scott; Stoinski, Tara; Bania, Amanda; Lonsdorf, Elizabeth; Schaeffer, Jennifer; Russell, Jamie; Hopkins, William D

    2015-01-01

    A number of factors have been proposed to influence within and between species variation in handedness in non-human 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 four 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. PMID:26635693

  1. Project Hand-Up. Helping Adolescents Needing Direction-Unlimited Partnership (HAND-UP): Stimulating Coordination and Linkage between Occupational Work Adjustment Programs and the Job Training Partnership Act (JTPA). Final Report.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Div. of Vocational and Career Education.

    Project HAND-UP (Helping Adolescents Needing Direction-Unlimited Partnership) was a 2-year program to enhance dropout prevention services to at-risk youth by establishing a closer linkage between Job Training Partnership (JTPA)-Ohio and the Ohio Department of Education's Occupational Work Adjustment (OWA) programs. The project's major activities…

  2. Hand Safety

    MedlinePlus

    ... en gatillo See More... Hand Anatomy Hand Safety Fireworks Safety Lawnmower Safety Snowblower safety Pumpkin Carving Gardening ... en gatillo See More... Hand Anatomy Hand Safety Fireworks Safety Lawnmower Safety Snowblower safety Pumpkin Carving Gardening ...

  3. Eye Emergencies

    MedlinePlus

    ... Emergencies Cardiac Emergencies Eye Emergencies Lung Emergencies Surgeries Eye Emergencies Marfan syndrome significantly increases your risk of ... light-sensitive membrane in the back of the eye (the retina) from its supporting layers. It is ...

  4. Eye Wear

    MedlinePlus

    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 ...

  5. Eye Injuries

    MedlinePlus

    The structure 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 ...

  6. Eye Cancer

    MedlinePlus

    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 ...

  7. Eye Diseases

    MedlinePlus

    ... the back of the eye Macular degeneration - a disease that destroys sharp, central vision Diabetic eye problems ... defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and ...

  8. Eye Injuries

    MedlinePlus

    ... 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 ...

  9. Dextrous robot hands

    NASA Technical Reports Server (NTRS)

    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.

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

    NASA Technical Reports Server (NTRS)

    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.

  11. Tie My Hands, Tie My Eyes

    ERIC Educational Resources Information Center

    Ambrosini, Ettore; Sinigaglia, Corrado; Costantini, Marcello

    2012-01-01

    Previous studies have demonstrated that motor abilities allow us not only to execute our own actions and to predict their consequences, but also to predict others' actions and their consequences. But just how deeply are motor abilities implicated in action observation? If an observer is prevented from acting while witnessing others' actions, will…

  12. A novel 3D Cu(I) coordination polymer based on Cu6Br2 and Cu2(CN)2 SBUs: in situ ligand formation and use as a naked-eye colorimetric sensor for NB and 2-NT.

    PubMed

    Song, Jiang-Feng; Li, Yang; Zhou, Rui-Sha; Hu, Tuo-Ping; Wen, Yan-Liang; Shao, Jia; Cui, Xiao-Bing

    2016-01-14

    A novel coordination polymer with the chemical formula [Cu4Br(CN)(mtz)2]n (mtz = 5-methyl tetrazole) (), has been synthesized under solvothermal conditions and characterized by elemental analysis, infrared (IR) spectroscopy, thermal gravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Interestingly, the Cu(i), CN(-) and mtz(-) in compound are all generated from an in situ translation of the original precursors: Cu(2+), acetonitrile and 1-methyl-5-mercapto-1,2,3,4-tetrazole (Hmnt). The in situ ring-to-ring conversion of Hmnt into mtz(-) was found for the first time. Structural analysis reveals that compound is a novel 3D tetrazole-based Cu(i) coordination polymer, containing both metal halide cluster Cu6Br2 and metal pseudohalide cluster Cu2(CN)2 secondary building units (SBUs), which shows an unprecedented (3,6,10)-connected topology. Notably, a pseudo-porphyrin structure with 16-membered rings constructed by four mtz(-) anions and four copper(i) ions was observed in compound . The fluorescence properties of compound were investigated in the solid state and in various solvent emulsions, the results show that compound is a highly sensitive naked-eye colorimetric sensor for NB and 2-NT (NB = nitrobenzene and 2-NT = 2-nitrotoluene). PMID:26600452

  13. Healthy Eyes

    MedlinePlus

    ... please turn Javascript on. Healthy Eyes Maintaining Your Vision Click for more information Taking good care of ... are qualified to perform eye exams. Aging and Vision Changes As you age, it is normal to ...

  14. Eye Cancer

    MedlinePlus

    ... adults are melanoma and lymphoma. The most common eye cancer in children is retinoblastoma, which starts in the cells of the retina. ... from other parts of the body. Treatment for eye cancer varies by the type and by how advanced ...

  15. Eye Anatomy

    MedlinePlus

    ... 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 ...

  16. Your Eyes

    MedlinePlus

    ... the eye and keeps it healthy. previous continue Light, Lens, Action These next parts are really cool, ... the eye. previous continue Rods and Cones Process Light The retina uses special cells called rods and ...

  17. Eye Problems

    MedlinePlus

    ... Do you have diabetes, and have you noticed any changes in your vision? Yes Over time, too much glucose (sugar) in the ... eye pink, red or irritated, and are there any secretions or mucus from the eye? Yes CONJUNCTIVITIS, also called "PINK EYE," can be caused ...

  18. Eye floaters

    MedlinePlus

    ... eyes are not on the surface of your eyes, but inside them. These floaters are bits of cell debris that drift around ... is the layer in the back of the eye.) If you notice a sudden increase in floaters or if you see floaters along with flashes ...

  19. The cell adhesion molecules Echinoid and Friend of Echinoid coordinate cell adhesion and cell signaling to regulate the fidelity of ommatidial rotation in the Drosophila eye.

    PubMed

    Fetting, Jennifer L; Spencer, Susan A; Wolff, Tanya

    2009-10-01

    Directed cellular movements are a universal feature of morphogenesis in multicellular organisms. Differential adhesion between the stationary and motile cells promotes these cellular movements to effect spatial patterning of cells. A prominent feature of Drosophila eye development is the 90 degrees rotational movement of the multicellular ommatidial precursors within a matrix of stationary cells. We demonstrate that the cell adhesion molecules Echinoid (Ed) and Friend of Echinoid (Fred) act throughout ommatidial rotation to modulate the degree of ommatidial precursor movement. We propose that differential levels of Ed and Fred between stationary and rotating cells at the initiation of rotation create a permissive environment for cell movement, and that uniform levels in these two populations later contribute to stopping the movement. Based on genetic data, we propose that ed and fred impart a second, independent, ;brake-like' contribution to this process via Egfr signaling. Ed and Fred are localized in largely distinct and dynamic patterns throughout rotation. However, ed and fred are required in only a subset of cells - photoreceptors R1, R7 and R6 - for normal rotation, cells that have only recently been linked to a role in planar cell polarity (PCP). This work also provides the first demonstration of a requirement for cone cells in the ommatidial rotation aspect of PCP. ed and fred also genetically interact with the PCP genes, but affect only the degree-of-rotation aspect of the PCP phenotype. Significantly, we demonstrate that at least one PCP protein, Stbm, is required in R7 to control the degree of ommatidial rotation. PMID:19736327

  20. Eye preferences in captive chimpanzees.

    PubMed

    Braccini, Stephanie N; Lambeth, Susan P; Schapiro, Steven J; Fitch, W Tecumseh

    2012-09-01

    Over the last century, the issue of brain lateralization in primates has been extensively investigated and debated, yet no previous study has reported eye preference in great apes. This study examined eye preference in 45 captive chimpanzees (Pan troglodytes) in response to various stimuli. Eye preference was assessed when animals looked through a hole that only accommodated one eye at an empty box, a mirror, a picture of a dog, a rubber snake, food biscuits, bananas, a rubber duck, and a video camera. Main effects of stimulus type were found for direction of eye preference, number of looks, and looking duration, but not for strength of eye preference. A left-eye bias was found for viewing the rubber snake and a right-eye bias was found for viewing the bananas, supporting theories that emotional valence may affect lateralized behaviors. In addition, a significant shift in eye preference took place from the initial look to subsequent looks when viewing the snake. These results are not consistent with previous reports of human eye preference and may reflect lateralization differences for emotional processing. No relationship between eye preference and previously recorded hand preference was found. PMID:22733385

  1. Eye development.

    PubMed

    Baker, Nicholas E; Li, Ke; Quiquand, Manon; Ruggiero, Robert; Wang, Lan-Hsin

    2014-06-15

    The eye has been one of the most intensively studied organs in Drosophila. The wealth of knowledge about its development, as well as the reagents that have been developed, and the fact that the eye is dispensable for survival, also make the eye suitable for genetic interaction studies and genetic screens. This article provides a brief overview of the methods developed to image and probe eye development at multiple developmental stages, including live imaging, immunostaining of fixed tissues, in situ hybridizations, and scanning electron microscopy and color photography of adult eyes. Also summarized are genetic approaches that can be performed in the eye, including mosaic analysis and conditional mutation, gene misexpression and knockdown, and forward genetic and modifier screens. PMID:24784530

  2. EYE DEVELOPMENT

    PubMed Central

    Baker, Nicholas E.; Li, Ke; Quiquand, Manon; Ruggiero, Robert; Wang, Lan-Hsin

    2014-01-01

    The eye has been one of the most intensively studied organs in Drosophila. The wealth of knowledge about its development, as well as the reagents that have been developed, and the fact that the eye is dispensable for survival, also make the eye suitable for genetic interaction studies and genetic screens. This chapter provides a brief overview of the methods developed to image and probe eye development at multiple developmental stages, including live imaging, immunostaining of fixed tissues, in situ hybridizations, and scanning electron microscopy and color photography of adult eyes. Also summarized are genetic approaches that can be performed in the eye, including mosaic analysis and conditional mutation, gene misexpression and knockdown, and forward genetic and modifier screens. PMID:24784530

  3. Hand Washing

    MedlinePlus

    ... dirty little secrets: Students don't wash their hands often or well. In one study, only 58% of female and 48% of male middle- and high-school students washed their hands after using the bathroom. Yuck! previous continue How ...

  4. Hand washing.

    PubMed

    2016-07-01

    A surgery matron has writt en a hand hygiene promotional video rap to encourage staff, patients and visitors to wash their hands. Vicky Cartwright from University Hospitals of Leicester NHS Trust rewrote the lyrics to 1990s hit rap, Ice Ice Baby. PMID:27380706

  5. Eye Injuries at Home

    MedlinePlus

    ... Patient Stories Español Eye Health / Tips & Prevention Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating Eye ... Sports Eye Injuries by the Numbers — Infographic Eye Injuries at Home Reviewed by: Brenda Pagan-Duran MD ...

  6. Robotic Hand

    NASA Technical Reports Server (NTRS)

    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.

  7. Dry Eye

    MedlinePlus

    ... surgery, called punctal cautery, is recommended to permanently close the drainage holes. The procedure helps keep the limited volume of tears on the eye for a longer period of time. In some patients with dry eye, supplements or dietary sources (such as tuna fish) of omega-3 fatty ...

  8. Eye Complications

    MedlinePlus

    ... the cornea, which focuses light while protecting the eye. After light passes through the cornea, it travels through a ... and have them progress faster. With cataracts, the eye's clear lens clouds, blocking light. To help deal with mild cataracts, you may ...

  9. Hand Eczema

    PubMed Central

    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

  10. What Happened to Service Coordination?

    ERIC Educational Resources Information Center

    McWilliam, R. A.

    2006-01-01

    Comments on an article by Dunst and Bruder. Service coordination was supposed to be one of the major jewels in the legislative crown for young children with disabilities and their families. The authors have cast their experienced eyes on the heart of the matter, which is the models of service coordination that sprang to life almost immediately…

  11. Healthy Eyes

    MedlinePlus

    ... Programs Training and Jobs Home > Healthy Eyes Healthy Vision Diabetes Diabetes Home How Much Do You Know? ... seeing your best. Read more. What are common vision problems? Some of the most common vision problems ...

  12. Eye Allergies

    MedlinePlus

    ... MD Mar. 01, 2015 Eye allergies, called allergic conjunctivitis , are a common condition that occurs when the ... with tearing and burning. Unlike bacterial or viral conjunctivitis, allergic conjunctivitis is not spread from person to ...

  13. Eye emergencies

    MedlinePlus

    ... and there is a good chance of recovery. Alkaline substances -- such as lime, lye, drain cleaners, and ... at high speed by machining, grinding, or hammering metal have the highest risk of injuring the eye. ...

  14. Eye Infections

    MedlinePlus

    ... Health Issues Conditions Abdominal ADHD Allergies & Asthma Autism Cancer Chest & Lungs Chronic Conditions Cleft & Craniofacial Developmental Disabilities Ear Nose & Throat Emotional Problems Eyes Fever From Insects or Animals Genitals and Urinary Tract Glands & Growth ...

  15. Aging and Your Eyes

    MedlinePlus

    ... Your Eyes Heath and Aging Aging and Your Eyes Steps to Protect Your Eyesight Common Eye Problems ... weight can also help protect your vision. Common Eye Problems The following common eye problems can be ...

  16. 33 CFR 401.42 - Passing hand lines.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... downbound vessel shall use its own hand lines, secured to the eye at the end of the mooring lines, by means... behind the splice of the eye; (3) At Iroquois Lock and Lock 8, Welland Canal, both upbound and downbound... to the eye of the No. 1 mooring wire by means of a bowline. (b) Mooring lines shall not be...

  17. Occupational eye injuries in Finland.

    PubMed

    Saari, K M; Parvi, V

    1984-01-01

    In Finland 11.9% of all industrial accidents in 1973 were eye injuries including superficial eye injuries (79.2%), ultraviolet burns of the cornea (3.9%), eye burns (3.6%), blunt ocular trauma (2,5%), wounds (2.4%), and post-traumatic infections (5.8%). Eye injuries constituted 34.3% of all industrial accidents which needed only ambulatory treatment and 17.5% of all industrial accidents causing an absence for 1-2 days. In 1981 2.1% of all compensated industrial accidents (incapacity for work 3 days or more) were eye injuries. Most compensated eye injuries occurred in manufacturing and in construction work (80.4%) and 8.5% occurred in agriculture. The annual incidence rates of compensated accidents to the eyes (accidents X 1 000/number of employees) were highest in several branches of metal industry (4.96-6.88), excavating and foundation work (6.88), and in logging (5.64). Compensated eye injuries were caused by machines (32.8%), hand tools (25.6%), other equipment and constructions (4.8%), work environment (23.6%), chemical substances (10.8%), and other accidents (2.3%). PMID:6328849

  18. Eye point-of-regard system

    NASA Technical Reports Server (NTRS)

    Jex, H. R.

    1971-01-01

    System measures intersection of line of sight and eye point of regard /EPR/ for a human operator in visual scanning system. Device measures two head to reference angles with EPR system and adds them with eye to head angles, yielding a dc signal proportional to picture plane coordinates.

  19. Eye tracker.

    PubMed

    Pruehsner, W; Enderle, J D

    1999-01-01

    A device that records saccadic eye movements, the Eye Tracker, is presented in this paper. The Eye Tracker utilizes infra-red technology mounted on fully adjustable goggles to follow eye movements targeted by either a goggles mounted HUD type display or a wall mounted light bank. Output from the goggles is remotely sent to a PC type computer, which leads to device portability. The goggles can also maintain output data in an internal memory for latter download. The user interface is Windows based with the output from the goggles represented as a trace map or plotted points. This output can also be saved or printed for future reference. The user interface can be used on any PC type computer. The device is designed with reference to standard ISO design methodology. Safety in design and final product usage has also been addressed with reference to standard ISO type procedures. Device accuracy is maintained by precise construction of the IR units in the goggles and tight control of cross talk between each IR device plus filtering of ambient light signals. Also, a reset feature is included to maintain equal baseline control. An automatic switching device is included in the goggles to allow the Eye Tracker to "warm up," assuring that equal IR power is delivered for each subject tested. The IR units in the goggles are also modular in case replacement is required. PMID:11143354

  20. Computing three-dimensional eye position quaternions and eye velocity from search coil signals.

    PubMed

    Tweed, D; Cadera, W; Vilis, T

    1990-01-01

    The four-component rotational operators called quaternions, which represent eye rotations in terms of their axes and angles, have several advantages over other representations of eye position (such as Fick coordinates): they provide easy computations, symmetry, a simple form for Listing's law, and useful three-dimensional plots of eye movements. In this paper we present algorithms for computing eye position quaternions and eye angular velocity (not the derivative of position in three dimensions) from two search coils (not necessarily orthogonal) on one eye in two or three magnetic fields, and for locating primary position using quaternions. We show how differentiation of eye position signals yields poor estimates of all three components of eye velocity. PMID:2321369

  1. Eye and orbit ultrasound

    MedlinePlus

    Echography - eye orbit; Ultrasound - eye orbit; Ocular ultrasonography; Orbital ultrasonography ... ophthalmology department of a hospital or clinic. Your eye is numbed with medicine (anesthetic drops). The ultrasound ...

  2. Hand rejuvenation.

    PubMed

    Riyaz, Farhaad R; Ozog, David

    2015-09-01

    Aging of the hands results from both natural processes and chronic ultraviolet light exposure. Together, these cause textural and pigmentary changes, excess skin laxity, rhytides, and soft tissue atrophy that presents as prominent bones and tendons with easily visible veins. Many options are available for the reversal of these changes. Photoaging can be improved with chemical peels and light-based treatments (such as Q-switched lasers), resurfacing lasers, intense pulsed light, and photodynamic therapy. Soft tissue atrophy can be corrected with autologous fat, nonanimal stabilized hyaluronic acid, calcium hydroxylapatite, and poly-L lactic acid injections. The literature shows that these treatments have favorable outcomes for most patients; but in order to reduce known complications, it is important to understand the proper use and limitations of each modality. PMID:26566571

  3. Dilating Eye Drops

    MedlinePlus

    ... Conditions Most Common Searches Adult Strabismus Amblyopia Cataract Conjunctivitis Corneal Abrasions Dilating Eye Drops Lazy eye (defined) ... Loading... Most Common Searches Adult Strabismus Amblyopia Cataract Conjunctivitis Corneal Abrasions Dilating Eye Drops Lazy eye (defined) ...

  4. Eye muscle repair - discharge

    MedlinePlus

    ... 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 ...

  5. Eye Movement Disorders

    MedlinePlus

    ... 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 ...

  6. Why Do Eyes Water?

    MedlinePlus

    ... Help White House Lunch Recipes Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? Print ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  7. Tracking with the mind's eye

    NASA Technical Reports Server (NTRS)

    Krauzlis, R. J.; Stone, L. S.

    1999-01-01

    The two components of voluntary tracking eye-movements in primates, pursuit and saccades, are generally viewed as relatively independent oculomotor subsystems that move the eyes in different ways using independent visual information. Although saccades have long been known to be guided by visual processes related to perception and cognition, only recently have psychophysical and physiological studies provided compelling evidence that pursuit is also guided by such higher-order visual processes, rather than by the raw retinal stimulus. Pursuit and saccades also do not appear to be entirely independent anatomical systems, but involve overlapping neural mechanisms that might be important for coordinating these two types of eye movement during the tracking of a selected visual object. Given that the recovery of objects from real-world images is inherently ambiguous, guiding both pursuit and saccades with perception could represent an explicit strategy for ensuring that these two motor actions are driven by a single visual interpretation.

  8. Novel automatic eye detection and tracking algorithm

    NASA Astrophysics Data System (ADS)

    Ghazali, Kamarul Hawari; Jadin, Mohd Shawal; Jie, Ma; Xiao, Rui

    2015-04-01

    The eye is not only one of the most complex but also the most important sensory organ of the human body. Eye detection and eye tracking are basement and hot issue in image processing. A non-invasive eye location and eye tracking is promising for hands-off gaze-based human-computer interface, fatigue detection, instrument control by paraplegic patients and so on. For this purpose, an innovation work frame is proposed to detect and tracking eye in video sequence in this paper. The contributions of this work can be divided into two parts. The first contribution is that eye filters were trained which can detect eye location efficiently and accurately without constraints on the background and skin colour. The second contribution is that a framework of tracker based on sparse representation and LK optic tracker were built which can track eye without constraint on eye status. The experimental results demonstrate the accuracy aspects and the real-time applicability of the proposed approach.

  9. Integrated and Independent Learning of Hand-Related Constituent Sequences

    ERIC Educational Resources Information Center

    Berner, Michael P.; Hoffmann, Joachim

    2009-01-01

    In almost all daily activities fingers of both hands are used in coordinated succession. The present experiments explored whether learning in such tasks pertains not only to the overall sequence spanning both hands but also to the constituent sequences of each hand. In a serial reaction time task, 2 repeating hand-related sequences were…

  10. Diabetes eye exams

    MedlinePlus

    ... catch problems early if you get regular eye exams. ... diabetes checks your eyes, you need an eye exam every 1 to 2 years by an eye ... problems with your vision. Many can do screening exams for damage from diabetes. Once you have eye ...

  11. The role of action prediction and inhibitory control for joint action coordination in toddlers.

    PubMed

    Meyer, M; Bekkering, H; Haartsen, R; Stapel, J C; Hunnius, S

    2015-11-01

    From early in life, young children eagerly engage in social interactions. Yet, they still have difficulties in performing well-coordinated joint actions with others. Adult literature suggests that two processes are important for smooth joint action coordination: action prediction and inhibitory control. The aim of the current study was to disentangle the potential role of these processes in the early development of joint action coordination. Using a simple turn-taking game, we assessed 2½-year-old toddlers' joint action coordination, focusing on timing variability and turn-taking accuracy. In two additional tasks, we examined their action prediction capabilities with an eye-tracking paradigm and examined their inhibitory control capabilities with a classic executive functioning task (gift delay task). We found that individual differences in action prediction and inhibitory action control were distinctly related to the two aspects of joint action coordination. Toddlers who showed more precision in their action predictions were less variable in their action timing during the joint play. Furthermore, toddlers who showed more inhibitory control in an individual context were more accurate in their turn-taking performance during the joint action. On the other hand, no relation between timing variability and inhibitory control or between turn-taking accuracy and action prediction was found. The current results highlight the distinct role of action prediction and inhibitory action control for the quality of joint action coordination in toddlers. Underlying neurocognitive mechanisms and implications for processes involved in joint action coordination in general are discussed. PMID:26150055

  12. Hand lotion poisoning

    MedlinePlus

    Hand lotion poisoning occurs when someone swallows hand lotion or hand cream. This article is for information only. DO ... These ingredients in hand lotion or cream can be harmful if swallowed: Dimethicone Mineral oil Paraffins (waxes) Petrolatum Various alcohols

  13. Eye muscle repair - discharge

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000111.htm Eye muscle repair - discharge To use the sharing features on ... enable JavaScript. You or your child had eye muscle repair surgery to correct eye muscle problems that ...

  14. Eye muscle repair - slideshow

    MedlinePlus

    ... 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. Dilating Eye Drops

    MedlinePlus

    ... 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 ( ...

  16. Fluorescent eye test (image)

    MedlinePlus

    The fluorescent eye test is useful in determining if there is a scratch or other problem with the surface ... has thoroughly covered the eye a cobalt blue light is then directed on the eye. The light ...

  17. Development of hand surgery: education of hand surgeons.

    PubMed

    Omer, G E

    2000-07-01

    An organized experience in the care of hand injuries and infections was not available until World War II, when military hand centers were established. Dr Sterling Bunnell was designated as a special civilian consultant to the Secretary of War. The surgeons in the military services during World War II became the nucleus of the American Society for Surgery of the Hand (ASSH). Following World War II and the Korean War there was a major shift toward medical subspecialization, and the growth of surgery of the hand as a subspecialty parallels that trend. The ASSH initiated a coordinated effort to improve the educational experience, and in 1967 the ASSH Resident Training Committee was evaluating hand training programs. The ASSH developed a comprehensive program in continuing medical education, and received full accreditation from the American Medical Association Council on Medical Education. The American Medical Association has included hand surgery on its list of designated specialties since 1975. In 1973, the bylaws of the American Board of Medical Specialties were revised to provide special certification. The ASSH developed a proposal for a certificate of added qualification in surgery of the hand that was presented to the three primary boards (orthopaedic, plastic, surgery) and the ad hoc joint Committee on Surgery of the Hand was organized in 1982. An application for a certificate of added qualification in surgery was developed by the Joint Committee on Surgery of the Hand and approved by all three boards in 1985 and the ABMS in 1986. The first examination for the certificate of added qualification in surgery was held in 1989. PMID:10913201

  18. Comparison of surgically induced astigmatism between one-handed and two-handed cataract surgery techniques

    PubMed Central

    Kawahara, Asushi; Kurosaka, Daijiro; Yoshida, Aktoshi

    2013-01-01

    Background The purpose of this study was to compare surgically induced astigmatism (SIA) between one-handed and two-handed cataract surgery techniques. Methods Eighty-eight eyes of 44 patients with no ocular disease other than cataract, who underwent cataract surgery by a single surgeon, were selected for this study. Cataract surgery was performed by coaxial phacoemulsification and intraocular lens implantation via a 2.4 mm transconjunctival single-plane sclerocorneal incision at the 12 o’clock position. In each patient, one eye was subjected to coaxial phacoemulsification using a one-handed technique while the fellow eye was subjected to coaxial phacoemulsification using a two-handed technique. For the two-handed technique, a corneal side port was created at the 2 o’clock position. The appropriate incision meridian was identified by a preoperative axis mark. SIA was calculated using the Alpins method. Results Mean SIA was 0.40 ± 0.28 diopters (D) in the one-handed technique group and 0.39 ± 0.25 D in the two-handed technique group. No statistically significant difference was found in the mean SIA score. The mean torque value was −0.05 ± 0.26 D in the one-handed technique group and 0.11 ± 0.37 D in the two-handed technique group. Mean torque was significantly lower (P<0.05) in the one-handed technique group than in the two-handed technique group. Conclusion The results indicate that the corneal side port in two-handed cataract surgery has a rotating effect on the axis of astigmatism. PMID:24124349

  19. Eyeing Ganymede

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Jupiter casts a baleful eye toward the moon Ganymede in this enhanced-contrast image from NASA's Cassini spacecraft.

    Jupiter's 'eye', the Great Red Spot, was captured just before disappearing around the eastern edge of the planet. The furrowed eyebrow above and to the left of the spot is a turbulent wake region caused by westward flow that has been deflected to the north and around the Red Spot. The smallest features visible are about 240 kilometers (150 miles) across.

    Within the band south of the Red Spot are a trio of white ovals, high pressure counterclockwise-rotating regions that are dynamically similar to the Red Spot. The dark filamentary features interspersed between white ovals are probably cyclonic circulations and, unlike the ovals, are rotating clockwise.

    Jupiter's equatorial zone stretching across the planet north of the Spot appears bright white, with gigantic plume clouds spreading out from the equator both to the northeast and to the southeast in a chevron pattern. This zone looks distinctly different than it did during the Voyager flyby 21 years ago. Then, its color was predominantly brown and the only white plumes conspicuous against the darker material beneath them were oriented southwest-to-northeast.

    Ganymede is Jupiter's largest moon, about 50 percent larger than our own Moon and larger than the planet Mercury. The visible details in this image are different geological terrains. Dark areas tend to be older and heavily cratered; brighter areas are younger and less cratered. Cassini images of Ganymede and Jupiter's other large moons taken near closest approach on Dec. 30 will have resolutions about four times better than that seen here.

    This image is a color composite of ones taken with different filters by Cassini's narrow-angle camera on Nov. 18, 2000, processed to enhance contrast. Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of

  20. 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.

    PubMed

    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. PMID:27253452

  1. Design of a computer game using an eye-tracking device for eye's activity rehabilitation

    NASA Astrophysics Data System (ADS)

    Lin, Chern-Sheng; Huan, Chia-Chin; Chan, Chao-Ning; Yeh, Mau-Shiun; Chiu, Chuang-Chien

    2004-07-01

    An eye mouse interface that can be used to operate a computer using the movement of the eyes is described. We developed this eye-tracking system for eye motion disability rehabilitation. When the user watches the screen of a computer, a charge-coupled device will catch images of the user's eye and transmit it to the computer. A program, based on a new cross-line tracking and stabilizing algorithm, will locate the center point of the pupil in the images. The calibration factors and energy factors are designed for coordinate mapping and blink functions. After the system transfers the coordinates of pupil center in the images to the display coordinate, it will determine the point at which the user gazed on the display, then transfer that location to the game subroutine program. We used this eye-tracking system as a joystick to play a game with an application program in a multimedia environment. The experimental results verify the feasibility and validity of this eye-game system and the rehabilitation effects for the user's visual movement.

  2. Degradation of Binocular Coordination during Sleep Deprivation

    PubMed Central

    Tong, Jianliang; Maruta, Jun; Heaton, Kristin J.; Maule, Alexis L.; Rajashekar, Umesh; Spielman, Lisa A.; Ghajar, Jamshid

    2016-01-01

    To aid a clear and unified visual perception while tracking a moving target, both eyes must be coordinated, so the image of the target falls on approximately corresponding areas of the fovea of each eye. The movements of the two eyes are decoupled during sleep, suggesting a role of arousal in regulating binocular coordination. While the absence of visual input during sleep may also contribute to binocular decoupling, sleepiness is a state of reduced arousal that still allows for visual input, providing a context within which the role of arousal in binocular coordination can be studied. We examined the effects of sleep deprivation on binocular coordination using a test paradigm that we previously showed to be sensitive to sleep deprivation. We quantified binocular coordination with the SD of the distance between left and right gaze positions on the screen. We also quantified the stability of conjugate gaze on the target, i.e., gaze–target synchronization, with the SD of the distance between the binocular average gaze and the target. Sleep deprivation degraded the stability of both binocular coordination and gaze–target synchronization, but between these two forms of gaze control the horizontal and vertical components were affected differently, suggesting that disconjugate and conjugate eye movements are under different regulation of attentional arousal. The prominent association found between sleep deprivation and degradation of binocular coordination in the horizontal direction may be used for a fit-for-duty assessment. PMID:27379009

  3. Degradation of Binocular Coordination during Sleep Deprivation.

    PubMed

    Tong, Jianliang; Maruta, Jun; Heaton, Kristin J; Maule, Alexis L; Rajashekar, Umesh; Spielman, Lisa A; Ghajar, Jamshid

    2016-01-01

    To aid a clear and unified visual perception while tracking a moving target, both eyes must be coordinated, so the image of the target falls on approximately corresponding areas of the fovea of each eye. The movements of the two eyes are decoupled during sleep, suggesting a role of arousal in regulating binocular coordination. While the absence of visual input during sleep may also contribute to binocular decoupling, sleepiness is a state of reduced arousal that still allows for visual input, providing a context within which the role of arousal in binocular coordination can be studied. We examined the effects of sleep deprivation on binocular coordination using a test paradigm that we previously showed to be sensitive to sleep deprivation. We quantified binocular coordination with the SD of the distance between left and right gaze positions on the screen. We also quantified the stability of conjugate gaze on the target, i.e., gaze-target synchronization, with the SD of the distance between the binocular average gaze and the target. Sleep deprivation degraded the stability of both binocular coordination and gaze-target synchronization, but between these two forms of gaze control the horizontal and vertical components were affected differently, suggesting that disconjugate and conjugate eye movements are under different regulation of attentional arousal. The prominent association found between sleep deprivation and degradation of binocular coordination in the horizontal direction may be used for a fit-for-duty assessment. PMID:27379009

  4. Technology coordination

    NASA Technical Reports Server (NTRS)

    Hartman, Steven

    1992-01-01

    Viewgraphs on technology coordination are provided. Topics covered include: technology coordination process to date; goals; how the Office of Aeronautics and Space Technology (OAST) can support the Office of Space Science and Applications (OSSA); how OSSA can support OAST; steps to technology transfer; and recommendations.

  5. Deficits of Visuospatial Attention with Reflexive Orienting Induced by Eye-Gazed Cues in Children with Developmental Coordination Disorder in the Lower Extremities: An Event-Related Potential Study

    ERIC Educational Resources Information Center

    Tsai, Chia-Liang; Pan, Chien-Yu; Chang, Yu-Kai; Wang, Chun-Hao; Tseng, Ko-Da

    2010-01-01

    The present study aims to investigate and compare the behavioral performance and event-related potentials (ERPs) measures in children with developmental coordination disorder (DCD) and typically developing (TD) children when performing the visuospatial attention task with reflexive orienting. Thirty children with DCD and 30 TD children were…

  6. Rubber hands feel the touch of light.

    PubMed

    Durgin, Frank H; Evans, Laurel; Dunphy, Natalie; Klostermann, Susan; Simmons, Kristina

    2007-02-01

    Two experiments involving a total of 220 subjects are reported. The experiments document that "stroking" a false hand with the bright beam of light from a laser pointer can produce tactile and thermal sensations when the hand can be seen as one's own. Overall, 66% of subjects reported somatic sensations from the light. Felt hand location was recalibrated toward the location of the false hand for those subjects who felt the light. Moreover, the proprioceptive recalibration from the laser experience was comparable to that produced by actual coordinated brushing of the false hand and of the unseen real hand after 2 min of stimulation. The illusion may be experienced on one's real hand as well. The results are discussed in terms of multisensory integration. PMID:17425536

  7. A new neural net approach to robot 3D perception and visuo-motor coordination

    NASA Technical Reports Server (NTRS)

    Lee, Sukhan

    1992-01-01

    A novel neural network approach to robot hand-eye coordination is presented. The approach provides a true sense of visual error servoing, redundant arm configuration control for collision avoidance, and invariant visuo-motor learning under gazing control. A 3-D perception network is introduced to represent the robot internal 3-D metric space in which visual error servoing and arm configuration control are performed. The arm kinematic network performs the bidirectional association between 3-D space arm configurations and joint angles, and enforces the legitimate arm configurations. The arm kinematic net is structured by a radial-based competitive and cooperative network with hierarchical self-organizing learning. The main goal of the present work is to demonstrate that the neural net representation of the robot 3-D perception net serves as an important intermediate functional block connecting robot eyes and arms.

  8. Hand Dominance and Common Hand Conditions.

    PubMed

    Lutsky, Kevin; Kim, Nayoung; Medina, Juana; Maltenfort, Mitchell; Beredjiklian, Pedro K

    2016-05-01

    The goals of this study were to (1) assess how frequently patients present for evaluation of common hand disorders in relation to hand dominance and (2) evaluate the effect of hand dominance on function in patients with these conditions. The authors hypothesized that (1) the majority of patients who seek evaluation would have a condition that affects the dominant hand, and (2) disability scores would be worse if the dominant hand is involved. They retrospectively reviewed the records of consecutive patients who presented for treatment to their institution with unilateral symptoms of 5 common disorders of the hand: carpal tunnel syndrome (CTS), de Quervain's tenosynovitis (DEQ), lateral epicondylitis (LE), hand osteoarthritis (OA), and trigger finger (TF). The authors assessed the effect of diagnosis and hand dominance on Disabilities of the Arm, Shoulder and Hand (DASH) scores. The study group comprised 1029 patients (379 men and 650 women) with a mean age of 59.5 years. Ninety percent were right-hand dominant. The dominant and nondominant hands were affected with relatively equal frequency for CTS, DEQ, OA, and TF (range, 45%-53%). Patients with LE had a significantly higher incidence of dominant hand involvement. Men had lower DASH scores than women by an average of 7.9 points, and DASH scores were significantly but slightly higher for the overall group (3.2 points) when the dominant side was affected. Men with LE and women with TF and OA had significantly higher DASH scores when their dominant extremity was affected. Common hand disorders such as CTS, DEQ, OA, and TF affect the dominant and nondominant hands in roughly equivalent proportions, whereas LE is more common on the dominant side. Dominant hand involvement results in significantly worse DASH scores, although the magnitude of this is relatively small. Women have significantly higher DASH scores than men for the conditions evaluated. [Orthopedics. 2016; 39(3):e444-e448.]. PMID:27018604

  9. Eating for Your Eyes

    ERIC Educational Resources Information Center

    Stastny, Sherri Nordstrom; Garden-Robinson, Julie

    2011-01-01

    An educational program targeting older adults was developed to increase knowledge regarding nutrition and eye health. With age, the chance for eye disease increases, so prevention is critical. The Eating for Your Eyes program has promoted behavior changes regarding eye health among the participants. This program is easily replicated and use is…

  10. Improving eye care in Rwanda

    PubMed Central

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

    2015-01-01

    Abstract Problem 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. Approach 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. Local setting Rwanda, an eastern African country of approximately 11 million people. Relevant changes 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. Lessons learnt 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. PMID:26240465

  11. Spontaneous eye blinks during creative task correlate with divergent processing.

    PubMed

    Ueda, Yoshiyuki; Tominaga, Atsuko; Kajimura, Shogo; Nomura, Michio

    2016-07-01

    Creativity consists of divergent and convergent thinking, with both related to individual eye blinks at rest. To assess underlying mechanisms between eye blinks and traditional creativity tasks, we investigated the relationship between creativity performance and eye blinks at rest and during tasks. Participants performed an alternative uses and remote association task while eye blinks were recorded. Results showed that the relationship between eye blinks at rest and creativity performance was compatible with those of previous research. Interestingly, we found that the generation of ideas increased as a function of eye blink number during the alternative uses task. On the other hand, during the remote association task, accuracy was independent of eye blink number during the task, but response time increased with it. Moreover, eye blink changes in participants who responded quickly during the remote association task were different depending on their resting state eye blinks; that is, participants with many eye blinks during rest showed little increasing eye blinks and achieved solutions quickly. Positive correlations between eye blinks during creative tasks and yielding ideas on the alternative uses task and response time on the remote association task suggest that eye blinks during creativity tasks relate to divergent thinking processes such as conceptual reorganization. PMID:25863791

  12. Hand lotion poisoning

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/002708.htm Hand lotion poisoning To use the sharing features on this page, please enable JavaScript. Hand lotion poisoning occurs when someone swallows hand lotion or ...

  13. Chapped hands (image)

    MedlinePlus

    Chapped hands can be sore and painful. Chapped hands may be soothed by the use of moisturizing lotions and the avoidance of excess exposure to water. If hands become badly chapped, hydrocortisone creams (available over the ...

  14. Hand splint - slideshow

    MedlinePlus

    ... 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 ...

  15. Following the Hand: The First Three Years of Life.

    ERIC Educational Resources Information Center

    Orion, Judy

    2001-01-01

    Discusses the development of the human hand from birth to age three as it contributes to the formation of human personality. Considers how parallels in eye, hand, brain, and motor skill development portray the evolving complexity and adaptation of the human grasp and illustrate Montessori theories about the relationship between physical experience…

  16. Impact of Virtual Environments on Sensorimotor Coordination and User Safety

    NASA Technical Reports Server (NTRS)

    Harm, Deborah L.; Taylor, Laura C.; Kennedy, Robert S.; Reschke, Millard F.

    2011-01-01

    One critical unresolved issue related to the safe use of virtual environments (VEs) is maladaptive sensorimotor coordination following exposure to VEs. Moving visual displays used in VEs, especially in the absence of concordant vestibular signals leads to adaptive responses during VE exposure, but maladaptive responses following return to the normal environment. In the current set of investigations, we examined the effect of HMD and dome VE displays on eye-head-hand coordination, gaze holding and postural equilibrium. Subjects (61) performed a navigation and a pick and place task. Further, we compared 30 min and 60 min exposures across 3 days (each separated by 1 day). A subset of these results will be presented. In general, we found significant decrements in all three measures following exposure to the VEs. In addition, we found that these disturbances generally recovered within 1-2 hrs and decreased across days. These findings suggest the need for post-VE monitoring of sensorimotor coordination and for developing a set of recommendations for users concerning activities that are safe to engage in following use of a VE.

  17. Acute Arterial Thrombosis of the Hand.

    PubMed

    Iannuzzi, Nicholas P; Higgins, James P

    2015-10-01

    Arterial thrombosis of the hand occurs infrequently but may result in considerable morbidity and compromise of hand function. The hand surgeon may be called upon to direct management in cases of acute arterial thrombosis of the hand and should have an understanding of the available diagnostic tools and treatment modalities. This article discusses the vascular anatomy of the hand and clinical manifestations of arterial thrombosis. Differences between isolated thrombosis and diffuse intravascular injury are detailed, and treatment options for these conditions are described. Appropriate care often requires coordination with interventional radiologists or vascular surgeons. Outcomes after treatment of arterial thrombosis of the hand are variable, and prognosis may be related to whether isolated thrombosis or diffuse intravascular injury is present. PMID:26408378

  18. HandsFree TLCMS

    Energy Science and Technology Software Center (ESTSC)

    2004-07-30

    The HandsFreeTLCMS software is able to - control an x,y,z stage connected to the computer via USB interface - automatically form and maintain the liquid junction between a TLC plate and the sampling probe of a TLC/MS surface sampler unit - automatically accomplish multiple-lane scans over a TLC plate making able to sample the whole surface by a pre-defined, reproducible, automated method - analyze mass spectrometric data collected during the surface scans and make datafilesmore » those contain x,y coordinates of surface spots (collected during the surface scans) and the corresponding mass signal intensities (integrated over a pre-defined m/z range) at those spots to produce 3-dimensional plots later in external graphic programs. - produce and save greyscale or color 2D pictures where X and Y axises of the picture correspond to the horizontal (x) and vertical (y) range of the scanned surface area and the color of a pixel is determined by the corresponding mass signal intensities (integrated over a pre-defined m/z range) at that X,Y spot« less

  19. HandsFree TLCMS

    SciTech Connect

    2004-07-30

    The HandsFreeTLCMS software is able to - control an x,y,z stage connected to the computer via USB interface - automatically form and maintain the liquid junction between a TLC plate and the sampling probe of a TLC/MS surface sampler unit - automatically accomplish multiple-lane scans over a TLC plate making able to sample the whole surface by a pre-defined, reproducible, automated method - analyze mass spectrometric data collected during the surface scans and make datafiles those contain x,y coordinates of surface spots (collected during the surface scans) and the corresponding mass signal intensities (integrated over a pre-defined m/z range) at those spots to produce 3-dimensional plots later in external graphic programs. - produce and save greyscale or color 2D pictures where X and Y axises of the picture correspond to the horizontal (x) and vertical (y) range of the scanned surface area and the color of a pixel is determined by the corresponding mass signal intensities (integrated over a pre-defined m/z range) at that X,Y spot

  20. Magnetosheath Coordinates

    NASA Astrophysics Data System (ADS)

    Schulz, M.; Chen, M. W.

    2010-12-01

    The eventual goal of this work is to develop an approximate analytical representation of solar-wind streamlines in the magnetosheath surrounding a magnetosphere of rather general shape. Previous analytical representations of magnetosheath streamlines and magnetic fields have invoked magnetopause shapes that conform to standard coordinate systems (e.g., spherical, cylindrical, paraboloidal, ellipsoidal), but it seems now that such a restriction on magnetopause shape is unnecessary. In the present work it is assumed only that the magnetopause is a continuously differentiable convex surface axisymmetric about the Sun-Earth line. This geometry permits the construction of an orthogonal coordinate system (mu, eta, chi) such that eta is the cosine of the cone angle between the Sun-Earth line and any conical surafce extending normally outward from the magnetopause, mu is a measure of the perpendicular distance of any magnetosheath point from the magnetopause, and chi is an azimuthal coordinate measured around the Sun-Earth line. It is convenient here to assign a label mu = mu* to the magnetopause itself, so that mu - mu* denotes perpendicular distance from the magnetopause and mu* is an adjustable parameter roughly comparable to the radius of the magnetotail. This choice provides for a rough correspondence between the (mu, eta, chi) coordinates introduced here and the ellipsoidal coordinates used in our previous efforts at magnetosheath modeling.

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

    PubMed

    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. PMID:24438993

  2. Wash Your Hands

    MedlinePlus

    ... do if you don't have soap and clean, running water? Washing hands with soap and water is the ... specific questions. More Information CDC's Handwashing Work Handwashing: Clean Hands Save Lives Hand Hygiene in Healthcare Settings Water-related Hygiene Hand Hygiene to Help Prevent Flu ...

  3. Infection after hand surgery.

    PubMed

    Eberlin, Kyle R; Ring, David

    2015-05-01

    Postoperative infections are uncommon after hand surgery. Infection can delay recovery and contribute to scarring and stiffness. Measures intended to reduce the risk of infection after hand surgery include hand washing, skin preparation, sterile technique, and prophylactic antibiotics. The role of prophylactic antibiotics for small, clean, elective hand surgery procedures lasting less than 2 hours is debated. PMID:25934209

  4. Pediatric Hand Injuries.

    PubMed

    Sullivan, Matthew A; Cogan, Charles J; Adkinson, Joshua M

    2016-01-01

    Pediatric hand injuries are extremely common. Although many hand injuries are adequately managed in the emergency department, some may need evaluation and treatment by a pediatric hand surgeon to ensure a good functional outcome. This article discusses the diagnosis and management of the most common pediatric hand maladies: fingertip injuries/amputation, tendon injuries, and phalangeal and metacarpal fractures. The plastic surgery nurse should be familiar with hand injuries that require intervention to facilitate efficient management and optimal postoperative care. PMID:27606586

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

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

    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 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. PMID:26912293

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

    PubMed Central

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

    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 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. PMID:26912293

  8. Lasik eye surgery - discharge

    MedlinePlus

    ... 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 ( ...

  9. Diabetic Eye Problems

    MedlinePlus

    ... too high. Over time, this can damage your eyes. The most common problem is diabetic retinopathy. It ... light-sensitive tissue at the back of your eye. You need a healthy retina to see clearly. ...

  10. Fluorescein eye stain

    MedlinePlus

    Abnormal results may point to: Abnormal tear production (dry eye) Blocked tear duct Corneal abrasion (a scratch on ... foreign object in ) Infection Injury or trauma Severe dry eye associated with arthritis (keratoconjunctivitis sicca)

  11. Eye Injuries at Work

    MedlinePlus

    ... Bureau of Labor Statistics, more than 20,000 workplace eye injuries happen each year. Injuries on the job often ... Occupational Safety and Health Administration (OSHA) reports that workplace eye injuries cost an estimated $300 million a year in ...

  12. Eye Injuries (For Parents)

    MedlinePlus

    ... eye nausea or vomiting after an eye injury Think Prevention! Kids who play sports should wear protective goggles or unbreakable glasses as needed. Keep chemicals and other potentially dangerous objects out of the reach of children. Reviewed by: ...

  13. Diabetic Eye Problems

    MedlinePlus

    ... this can damage your eyes. The most common problem is diabetic retinopathy. It is a leading cause ... surgery, with follow-up care. Two other eye problems can happen to people with diabetes. A cataract ...

  14. Eye muscle repair

    MedlinePlus

    ... Your child's eyes should look normal a few weeks after the surgery. ... Surgical Approach to the Rectus Muscles. In: Tasman W, Jaeger EA, ... Hug D, Plummer LS, Stass-Isern M. Disorders of eye movement and ...

  15. Anatomy of the Eye

    MedlinePlus

    ... Examinations, Adults Patient Eye Examinations, Children Refractive Errors Scientists in the Laboratory Visual Acuity Testing Anatomy of the Eye × Warning message Automatic fallback to the cURL connection method kicked in to handle the request. Result code ...

  16. Patient Eye Examinations - Adults

    MedlinePlus

    ... Examinations, Adults Patient Eye Examinations, Children Refractive Errors Scientists in the Laboratory Visual Acuity Testing Patient Eye Examinations, Adults × Warning message Automatic fallback to the cURL connection method kicked in to handle the request. Result code ...

  17. Eye muscle repair

    MedlinePlus

    ... and physical exam before the procedure Orthoptic measurements (eye movement measurements) Always tell your child's doctor or nurse: ... D, Plummer LS, Stass-Isern M. Disorders of eye movement and alignment. In: Kliegman RM, Behrman RE, Jenson ...

  18. Eye Injuries (For Parents)

    MedlinePlus

    ... and comfortable as possible until help arrives. continue Chemical Exposure Many chemicals, even those found around the house, can damage an eye. If your child gets a chemical in the eye and you know what it ...

  19. Diabetes - eye care

    MedlinePlus

    ... dilated eye exam. This is called digital retinal photography. Your eye doctor may ask you to come ... doctor if: You cannot see well in dim light. You have blind spots. You have double vision ( ...

  20. Diabetes and eye disease

    MedlinePlus

    ... the eye that can lead to blindness Macular edema: blurry vision due to fluid leaking into the ... in your retina (neovascularization) or you develop macular edema, treatment is usually needed. Eye surgery is the ...

  1. Eye and orbit ultrasound

    MedlinePlus

    ... the eye (vitreous hemorrhage) Cancer of the retina ( retinoblastoma ), under the retina, or in other parts of ... Cataract removal Melanoma of the eye Retinal detachment Retinoblastoma Ultrasound Update Date 2/23/2015 Updated by: ...

  2. Down Syndrome: Eye Problems

    MedlinePlus

    ... life expectancy. Do children with Down syndrome have eye problems? Individuals with Down syndrome are at increased ... When should children with Down syndrome receive an eye exam? The American Academy of Pediatrics recommends that ...

  3. Toxoplasmosis (and the Eye)

    MedlinePlus

    ... of known infected babies. What happens to the eyes of babies born with congenital toxoplasmosis? The infection ... to further reduce the inflammation. Updated 03/2015 Eye Terms & Conditions Most Common Searches Adult Strabismus Amblyopia ...

  4. Sports and Your Eyes

    MedlinePlus

    ... Glossary The Visual System Your Eyes’ Natural Defenses Eye Health and Safety First Aid Tips Healthy Vision ... More Information Optical Illusions Printables Sports and Your Eyes Gear up! If you play sports, you know ...

  5. Diabetes eye exams

    MedlinePlus

    ... are near. Sunlight can damage your eye. Wear dark glasses or shade your eyes until the effects ... to the principles of the Health on the Net Foundation (www.hon.ch). The information provided herein ...

  6. Anatomy of the Eye

    MedlinePlus

    ... it becomes red or pink. This is called conjunctivitis or “pinkeye”. Lacrimal Gland: The lacrimal gland produces tears that ... Conditions Most Common Searches Adult Strabismus Amblyopia Cataract Conjunctivitis Corneal Abrasions Dilating Eye Drops Lazy eye (defined) ...

  7. Eye - foreign object in

    MedlinePlus

    ... medlineplus.gov/ency/article/002084.htm Eye - foreign object in To use the sharing features on this ... Blinking The eye will often flush out small objects, like eyelashes and sand, through blinking and tearing. ...

  8. COORDINATED AV.

    ERIC Educational Resources Information Center

    CLEAVES, PAUL C.; AND OTHERS

    THE INSTRUCTIONAL MATERIALS CENTER IS LOCATED IN THE LOCAL HIGH SCHOOL AND SUPPLIES ALL SCHOOLS IN THE AREA. AUDIOVISUAL EQUIPMENT ORDERS, AFTER SELECTIONS ARE MADE BY THE CLASSROOM TEACHER, ARE PROCESSED BY THE CENTER, CONFIRMED AND DELIVERED BY TRUCK THREE TIMES EACH WEEK. EACH SCHOOL HAS A BUILDING COORDINATOR WHO CHECKS THE ORDERS INTO THE…

  9. Eye Carduino: A Car Control System using Eye Movements

    NASA Astrophysics Data System (ADS)

    Kumar, Arjun; Nagaraj, Disha; Louzardo, Joel; Hegde, Rajeshwari

    2011-12-01

    Modern automotive systems are rapidly becoming highly of transportation, but can be a web integrated media centre. This paper explains the implementation of a vehicle control defined and characterized by embedded electronics and software. With new technologies, the vehicle industry is facing new opportunities and also new challenges. Electronics have improved the performance of vehicles and at the same time, new more complex applications are introduced. Examples of high level applications include adaptive cruise control and electronic stability programs (ESP). Further, a modern vehicle does not have to be merely a means using only eye movements. The EyeWriter's native hardware and software work to return the co-ordinates of where the user is looking. These co-ordinates are then used to control the car. A centre-point is defined on the screen. The higher on the screen the user's gaze is, the faster the car will accelerate. Braking is done by looking below centre. Steering is done by looking left and right on the screen.

  10. Get Your Eyes Tested

    MedlinePlus

    ... over age 40 Have a family history of glaucoma Have diabetes People with diabetes may need eye exams more ... or if you have a family member with diabetes or an eye disease. Eye diseases like glaucoma can lead to vision loss and blindness if ...

  11. Dwarf Eye Disorder

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Johns Hopkins researchers at the Wilmer Eye Institute have discovered what appears to be the first human gene mutation that causes extreme farsightedness. The researchers report that nanophthalmos, Greek for "dwarf eye," is a rare, potentially blinding disorder caused by an alteration in a gene called MFRP that helps control eye growth and…

  12. Eye muscle proprioception is represented bilaterally in the sensorimotor cortex

    PubMed Central

    Balslev, Daniela; Albert, Neil B.; Miall, Chris

    2016-01-01

    The cortical representation of eye position is still uncertain. In the monkey a proprioceptive representation of the extraocular muscles (EOM) of an eye were recently found within the contralateral central sulcus. In humans, we have previously shown a change in the perceived position of the right eye after a virtual lesion with rTMS over the left somatosensory area. However, it is possible that the proprioceptive representation of the EOM extends to other brain sites, which were not examined in these previous studies. The aim of this fMRI study was to sample the whole brain to identify the proprioceptive representation for the left and the right eye separately. Data were acquired while passive eye movement was used to stimulate EOM proprioceptors in the absence of a motor command. We also controlled for the tactile stimulation of the eyelid by removing from the analysis voxels activated by eyelid touch alone. For either eye, the brain area commonly activated by passive and active eye movement was located bilaterally in the somatosensory area extending into the motor and premotor cytoarchitectonic areas. We suggest this is where EOM proprioception is processed. The bilateral representation for either eye contrasts with the contralateral representation of hand proprioception. We suggest that the proprioceptive representation of the two eyes next to each other in either somatosensory cortex and extending into the premotor cortex reflects the integrative nature of the eye position sense, which combines proprioceptive information across the two eyes with the efference copy of the oculomotor command. PMID:21391252

  13. Find a Hand Surgeon

    MedlinePlus

    ... Hand Safety Fireworks Safety Lawnmower Safety Snowblower safety Pumpkin Carving Gardening Safety Turkey Carving Removing a Ring ... Hand Safety Fireworks Safety Lawnmower Safety Snowblower safety Pumpkin Carving Gardening Safety Turkey Carving Removing a Ring ...

  14. Hand fracture - aftercare

    MedlinePlus

    ... 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 ...

  15. Hands-Only CPR

    MedlinePlus

    ... Instructors ECC Educational Conferences Programs CPR In Schools Hands-Only CPR Community CPR Tracker AED Implementation OSHA and AHA Alliance Be The Beat Hands-Only CPR Program Recursos para hispanohablantes en EE ...

  16. Hand and Finger Exercises

    MedlinePlus

    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 ____ ...

  17. Hand Injuries and Disorders

    MedlinePlus

    ... for a living, you are always using your hands. When there is something wrong with them, you ... not be able to do your regular activities. Hand problems include Carpal tunnel syndrome - compression of a ...

  18. Tokamak coordinate conventions: COCOS

    NASA Astrophysics Data System (ADS)

    Sauter, O.; Medvedev, S. Yu.

    2013-02-01

    Dealing with electromagnetic fields, in particular current and related magnetic fields, yields "natural" physical vector relations in 3-D. However, when it comes to choosing local coordinate systems, the "usual" right-handed systems are not necessarily the best choices, which means that there are several options being chosen. In the magnetic fusion community such a difficulty exists for the choices of the cylindrical and of the toroidal coordinate systems. In addition many codes depend on knowledge of an equilibrium. In particular, the Grad-Shafranov axisymmetric equilibrium solution for tokamak plasmas, ψ, does not depend on the sign of the plasma current Ip nor that of the magnetic field B0. This often results in ill-defined conventions. Moreover the sign, amplitude and offset of ψ are of less importance, since the free sources in the equation depend on the normalized radial coordinate. The signs of the free sources, dp/dψ and dF2/dψ (p being the pressure, ψ the poloidal magnetic flux and F=RBφ), must be consistent to generate the current density profile. For example, RF and CD calculations (Radio Frequency heating and Current Drive) require an exact sign convention in order to calculate a co- or counter-CD component. It is shown that there are over 16 different coordinate conventions. This paper proposes a unique identifier, the COCOS convention, to distinguish between the 16 most-commonly used options. Given the present worldwide efforts towards code integration, the proposed new index COCOS defining uniquely the COordinate COnventionS required as input by a given code or module is particularly useful. As codes use different conventions, it is useful to allow different sign conventions for equilibrium code input and output, equilibrium being at the core of any calculations in magnetic fusion. Additionally, given two different COCOS conventions, it becomes simple to transform between them. The relevant transformations are described in detail.

  19. Hand x-ray

    MedlinePlus

    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 ...

  20. Kaiser Permanente National Hand Hygiene Program

    PubMed Central

    Barnes, Sue; Barron, Dana; Becker, Linda; Canola, Teresa; Salemi, Charles

    2004-01-01

    Objective: Hand hygiene has historically been identified as an important intervention for preventing infection acquired in health care settings. Recently, the advent of waterless, alcohol-based skin degermer and elimination of artificial nails have been recognized as other important interventions for preventing infection. Supplied with this information, the National Infection Control Peer Group convened a KP Hand Hygiene Work Group, which, in August 2001, launched a National Hand Hygiene Program initiative titled “Infection Control: It’s In Our Hands” to increase compliance with hand hygiene throughout the Kaiser Permanente (KP) organization. Design: The infection control initiative was designed to include employee and physician education as well as to implement standard hand hygiene products (eg, alcohol degermers), eliminate use of artificial nails, and monitor outcomes. Results: From 2001 through September 2003, the National KP Hand Hygiene Work Group coordinated implementation of the Hand Hygiene initiative throughout the KP organization. To date, outcome monitoring has shown a 26% increase in compliance with hand hygiene as well as a decrease in the number of bloodstream infections and methycillin-resistant Staphylococcus aureus (MRSA) infections. As of May 2003, use of artificial nails had been reduced by 97% nationwide. Conclusions: Endorsement of this Hand Hygiene Program initiative by KP leadership has led to implementation of the initiative at all medical centers throughout the KP organization. Outcome indicators to date suggest that the initiative has been successful; final outcome monitoring will be completed in December 2003. PMID:26704605

  1. Removable hand hold

    NASA Technical Reports Server (NTRS)

    Corrigan, Robert D. (Inventor); Hauer, Robert L. (Inventor)

    1992-01-01

    A hand hold utilizes joining mechanisms which comprises two different mounting brackets that are permanently fastened to a supporting structure. A slide plate is disposed at one end of the hand rail or hand hold which mates with one of the mounting brackets. A securing member is disposed at the opposite end of the hand rail/hand hold which connects with the other mounting bracket by means of a locking device. The slide plate has a central tapered tongue with two matching slots disposed on each side thereof.

  2. Fungal and Parasitic Infections of the Eye

    PubMed Central

    Klotz, Stephen A.; Penn, Christopher C.; Negvesky, Gerald J.; Butrus, Salim I.

    2000-01-01

    The unique structure of the human eye as well as exposure of the eye directly to the environment renders it vulnerable to a number of uncommon infectious diseases caused by fungi and parasites. Host defenses directed against these microorganisms, once anatomical barriers are breached, are often insufficient to prevent loss of vision. Therefore, the timely identification and treatment of the involved microorganisms are paramount. The anatomy of the eye and its surrounding structures is presented with an emphasis upon the association of the anatomy with specific infection of fungi and parasites. For example, filamentous fungal infections of the eye are usually due to penetrating trauma by objects contaminated by vegetable matter of the cornea or globe or, by extension, of infection from adjacent paranasal sinuses. Fungal endophthalmitis and chorioretinitis, on the other hand, are usually the result of antecedent fungemia seeding the ocular tissue. Candida spp. are the most common cause of endogenous endophthalmitis, although initial infection with the dimorphic fungi may lead to infection and scarring of the chorioretina. Contact lens wear is associated with keratitis caused by yeasts, filamentous fungi, and Acanthamoebae spp. Most parasitic infections of the eye, however, arise following bloodborne carriage of the microorganism to the eye or adjacent structures. PMID:11023963

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

    PubMed

    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. PMID:26486363

  4. Prevention of Eye Injuries

    PubMed Central

    Pashby, Tom

    1981-01-01

    In Canada 30,000 people are registered as blind; in one third of these, blindness might have been avoided. Prevention is the key to reducing the number of eye injuries and blind eyes. The role of the family physician in early identification of treatable conditions and in the education of patients is discussed, but responsibility for prevention belongs to all physicians. The success of prevention is seen in the great reduction in eye injuries in industry and sports since eye protectors have been commonly used. However, many dangers to the eyes are either not recognized or are not taken seriously enough. This paper discusses some of the common causes of serious eye injuries in the home, in sports and in industry. Imagesp464-aFig. 1Fig. 2Fig. 3Fig. 4 PMID:21289691

  5. Anterior eye development and ocular mesenchyme

    PubMed Central

    Cvekl, Aleš; Tamm, Ernst R.

    2007-01-01

    Summary During development of the anterior eye segment, cells that originate from the surface epithelium or the neuroepithelium need to interact with mesenchymal cells, which predominantly originate from the neural crest. Failures of proper interaction result in a complex of developmental disorders such Peters’ anomaly, Axenfeld-Rieger’s syndrome or aniridia. Here we review the role of transcription factors that have been identified to be involved in the coordination of anterior eye development. Among these factors is PAX6, which is active in both epithelial and mesenchymal cells during ocular development, albeit at different doses and times. We propose that PAX6 is a key element that synchronizes the complex interaction of cell types of different origin, which are all needed for proper morphogenesis of the anterior eye. We discuss several molecular mechanisms that might explain the effects of haploinsufficiency of PAX6 and other transcription factors, and the broad variation of the resulting phenotypes. PMID:15057935

  6. Eye preferences in capuchin monkeys (Sapajus apella).

    PubMed

    Wilson, Duncan A; Tomonaga, Masaki; Vick, Sarah-Jane

    2016-07-01

    This study explored whether capuchin monkey eye preferences differ systematically in response to stimuli of positive and negative valence. The 'valence hypothesis' proposes that the right hemisphere is more dominant for negative emotional processing and the left hemisphere is more dominant for positive emotional processing. Visual information from each eye is thought to be transferred faster to and primarily processed by the contralateral cerebral hemisphere. Therefore, it was predicted capuchin monkeys would show greater left eye use for looking at negative stimuli and greater right eye use for looking at positive stimuli. Eleven captive capuchin monkeys were presented with four images of different emotional valence (an egg and capuchin monkey raised eyebrow face were categorised as positive, and a harpy eagle face and capuchin monkey threat face were categorised as negative) and social relevance (consisting of capuchin monkey faces or not), and eye preferences for viewing the stimuli through a monocular viewing hole were recorded. While strong preferences for using either the left or right eye were found for most individuals, there was no consensus at the population level. Furthermore, the direction of looking, number of looks and duration of looks did not differ significantly with the emotional valence of the stimuli. These results are inconsistent with the main hypotheses about the relationship between eye preferences and processing of emotional stimuli. However, the monkeys did show significantly more arousal behaviours (vocalisation, door-touching, self-scratching and hand-rubbing) when viewing the negatively valenced stimuli than the positively valenced stimuli, indicating that the stimuli were emotionally salient. These findings do not provide evidence for a relationship between eye preferences and functional hemispheric specialisations, as often proposed in humans. Additional comparative studies are required to better understand the phylogeny of lateral

  7. Multilevel coordination stability: Integrated goal representations in simultaneous intra-personal and inter-agent coordination

    PubMed Central

    Keller, Peter E.; Repp, Bruno H.

    2008-01-01

    The influence of integrated goal representations on multilevel coordination stability was investigated in a task that required finger tapping in antiphase with metronomic tone sequences (inter-agent coordination) while alternating between the two hands (intra-personal coordination). The maximum rate at which musicians could perform this task was measured when taps did or did not trigger feedback tones. Tones produced by the two hands (very low, low, medium, high, very high) could be the same as, or different from, one another and the (medium-pitched) metronome tones. The benefits of feedback tones were greatest when they were close in pitch to the metronome and the left hand triggered low tones while the right hand triggered high tones. Thus, multilevel coordination was facilitated by tones that were easy to integrate with, but perceptually distinct from, the metronome, and by compatibility of movement patterns and feedback pitches. PMID:18486931

  8. Perceptual changes of interaction between hand and object in an experimental phantom hand.

    PubMed

    Inui, Nobuyuki; Masumoto, Junya

    2015-01-01

    The authors examined whether the wrist and elbow were perceived as flexed when a stick was fixed to the hand while the joints were extended during anesthesia. Ten healthy participants lay on their back on a bed with their eyes closed, and a stick was fixed to their right hand. Surprisingly, while the perceived position of the wrist and elbow moved toward flexion from 10 to 40 min after the ischemic block, the stick fixed to the hand was also perceived as having moved toward flexion from 10 to 20 min after the block. Such coupling the change in the perceived stick position with the change in body image suggests a new type of hand-object illusion. PMID:25272048

  9. Tropical diabetic hand syndrome.

    PubMed

    Tiwari, Sangeeta; Chauhan, Ashutosh; Sethi, N T

    2008-10-01

    Tropical diabetic hand syndrome (TDHS) is a terminology used to describe a specific complication affecting patients with diabetes mellitus in the tropics. The syndrome encompasses a localized cellulitis with variable swelling and ulceration of the hands to progressive, fulminant hand sepsis, potentially fatal. Since this syndrome is less recognized it is often under-reported. Authors present two cases of TDHS and emphasize on aggressive glycemic control and surgical therapy to prevent potential crippling or fatal complications. PMID:20165601

  10. Hand Hygiene: An Update.

    PubMed

    Bolon, Maureen K

    2016-09-01

    The medical field has long recognized the importance of hand hygiene in preventing health care-associated infections, yet studies indicate that this important task is performed only 40% of the time. Health care workers cite several barriers to optimal performance of hand hygiene, but the time required to perform this task is foremost among them. Introduction of alcohol-based hand rubs, bundled interventions, and incorporation of technologies designed to monitor and promote hand hygiene all represent promising advances in this field. PMID:27515139

  11. Videos from the National Eye Institute: Eye Diseases

    MedlinePlus

    ... this page please turn Javascript on. Feature: Vision Videos from the National Eye Institute: Eye Diseases Past ... the early detection of eye disease. Share these videos with friends, family and colleagues. www.nei.nih. ...

  12. Adaptive Changes in Sensorimotor Coordination and Motion Sickness Following Repeated Exposures to Virtual Environments

    NASA Technical Reports Server (NTRS)

    Harm, D. L.; Taylor, L. C.; Bloomberg, J. J.

    2007-01-01

    Virtual environments offer unique training opportunities, particularly for training astronauts and preadapting them to the novel sensory conditions of microgravity. Two unresolved human factors issues in virtual reality (VR) systems are: 1) potential "cybersickness", and 2) maladaptive sensorimotor performance following exposure to VR systems. Interestingly, these aftereffects are often quite similar to adaptive sensorimotor responses observed in astronauts during and/or following space flight. Initial interpretation of novel sensory information may be inappropriate and result in perceptual errors. Active exploratory behavior in a new environment, with resulting feedback and the formation of new associations between sensory inputs and response outputs, promotes appropriate perception and motor control in the new environment. Thus, people adapt to consistent, sustained alterations of sensory input such as those produced by microgravity, unilateral labyrinthectomy and experimentally produced stimulus rearrangements. The purpose of this research was to compare disturbances in sensorimotor coordination produced by dome and head-mounted virtual environment displays and to examine the effects of exposure duration, and repeated exposures to VR systems. The first study examined disturbances in balance control, and the second study examined disturbances in eye-head-hand (EHH) and eye-head coordination.

  13. Photorefraction of the Eye

    ERIC Educational Resources Information Center

    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…

  14. Eye tissues study

    NASA Astrophysics Data System (ADS)

    Tuchin, Valery V.; Bashkatov, Alexey N.; Maksimova, Irina L.; Sinichkin, Yurii P.; Simonenko, Georgy V.; Genina, Elina A.; Lakodina, Nina A.

    2001-08-01

    Theoretical and in vitro and in vivo experimental study of spectral and polarization characteristics of the human and rabbit eye tissues are presented. The possibility of control of optical properties of eye cornea, lens and sclera is discussed and realized experimentally for glucose solution as the refractive index matching factor.

  15. Preventing Eye Injuries

    MedlinePlus

    ... Eye Injuries Reviewed by: Brenda Pagan-Duran MD Mar. 01, 2016 Protecting your eyes from injury is one of the most basic things you can do to keep your vision healthy throughout your life. You may be somewhat aware of the possible ...

  16. Lasik eye surgery - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100206.htm Lasik eye surgery - series To use the sharing features ... A.M. Editorial team. Related MedlinePlus Health Topics Laser Eye Surgery A.D.A.M., Inc. is accredited by ...

  17. Diabetes and eye disease

    MedlinePlus

    ... the back of the inner eye. It changes light and images that enter the eye into nerve signals, which are sent to the brain. Diabetic retinopathy is a main cause of decreased vision or blindness in Americans 20 to 74 years old. People with type 1 or type 2 ...

  18. Fluorescein eye stain

    MedlinePlus

    ... eye. The health care provider then shines a blue light at your eye. Any problems on the surface of the cornea will be stained by the dye and appear green under the blue light. The provider can determine the location and ...

  19. Understanding pink eye

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  20. A Helping Hand.

    ERIC Educational Resources Information Center

    Renner, Jason M.

    2000-01-01

    Discusses how designing a hand washing-friendly environment can help to reduce the spread of germs in school restrooms. Use of electronic faucets, surface risk management, traffic flow, and user- friendly hand washing systems that are convenient and maximally hygienic are examined. (GR)

  1. Eye burning - itching and discharge

    MedlinePlus

    ... allergies or hay fever Infections, bacterial or viral ( conjunctivitis or pink eye) Chemical irritants (such as chlorine ... to help with allergies. Pink eye or viral conjunctivitis causes a red or bloodshot eye and excessive ...

  2. Direct coupling of haptic signals between hands.

    PubMed

    Dupin, Lucile; Hayward, Vincent; Wexler, Mark

    2015-01-13

    Although motor actions can profoundly affect the perceptual interpretation of sensory inputs, it is not known whether the combination of sensory and movement signals occurs only for sensory surfaces undergoing movement or whether it is a more general phenomenon. In the haptic modality, the independent movement of multiple sensory surfaces poses a challenge to the nervous system when combining the tactile and kinesthetic signals into a coherent percept. When exploring a stationary object, the tactile and kinesthetic signals come from the same hand. Here we probe the internal structure of haptic combination by directing the two signal streams to separate hands: one hand moves but receives no tactile stimulation, while the other hand feels the consequences of the first hand's movement but remains still. We find that both discrete and continuous tactile and kinesthetic signals are combined as if they came from the same hand. This combination proceeds by direct coupling or transfer of the kinesthetic signal from the moving to the feeling hand, rather than assuming the displacement of a mediating object. The combination of signals is due to perception rather than inference, because a small temporal offset between the signals significantly degrades performance. These results suggest that the brain simplifies the complex coordinate transformation task of remapping sensory inputs to take into account the movements of multiple body parts in haptic perception, and they show that the effects of action are not limited to moving sensors. PMID:25548179

  3. Cue predictability changes scaling in eye-movement fluctuations.

    PubMed

    Wallot, Sebastian; Coey, Charles A; Richardson, Michael J

    2015-10-01

    Recent research has provided evidence for scaling-relations in eye-movement fluctuations, but not much is known about what these scaling relations imply about cognition or eye-movement control. Generally, scaling relations in behavioral and neurophysiological data have been interpreted as an indicator for the coordination of neurophysiological and cognitive processes. In this study, we investigated the effect of predictability in timing and gaze-direction on eye-movement fluctuations. Participants performed a simple eye-movement task, in which a visual cue prompted their gaze to different locations on a spatial layout, and the predictability about temporal and directional aspects of the cue were manipulated. The results showed that scaling exponents in eye-movements decreased with predictability and were related to the participants' perceived effort during the task. In relation to past research, these findings suggest that scaling exponents reflect a relative demand for voluntary control during task performance. PMID:26337612

  4. 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

    PubMed Central

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

    2016-01-01

    ABSTRACT 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. PMID:27253452

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

    ERIC Educational Resources Information Center

    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)

  6. European Hands-on Universe

    NASA Astrophysics Data System (ADS)

    Doran, Rosa; Ferlet, Roger; Gómez de Castro, Ana I.; Hill, Robert; Horellou, Cathy; Mankiewicz, Lech; Melchior, Anne-Laure; Metaxa, Margarita; Zanazzi, Alessandra

    2007-08-01

    Hands-on Universe is a project born at UC@Berkeley. A project devoted to enrich the teaching of Astronomy within the classroom environment with a different approach, more connected to the new technologies. Its main goals are not only to promote the use of such technologies but also to reawaken on students the taste for STEM (Science, technologies, engineering and math) related issues and also to increase their scientific culture. Eight countries in Europe decided to adopt the method and, funded by MINERVA, formed the European Hands-on Universe. Several resources were produced and a data reduction software developed http://www.euhou.net/.Other European countries are interested and should join this coordinated effort in the near future. At an international level there are 20 countries using this approach. There are plans to develop scientific cooperation among these countries. Pilot scientific research projects in schools are being tested in EU-HOU schools, Russia and USA. There is also a game being developed to be used as a new tool for teaching scientific content in the classroom environment. An effort to develop an international network of scientific / educational collaboration is the next step.

  7. [The hand and rheumatism].

    PubMed

    Lioté, F; Chicheportiche, V

    1997-01-01

    The hand is a major site of musculoskeletal disorders. Clinical features to be studied include the patient's age and sex, pain, stiffness, range of motion of the various joints of the wrists and hands, soft tissue swelling (particularly tendons sheaths), bone excrescences, skin changes. Radiological abnormalities in the hands, if any, may confirm the clinical diagnosis. The main features of rheumatoid arthritis, systemic lupus erythematosus, psoriatic arthritis, erosive degenerative changes, Südeck syndrome, calcium pyrophosphate dihydrate deposition disease, etc., are reviewed. PMID:9810076

  8. Facial and Hand Allotransplantation

    PubMed Central

    Pomahac, Bohdan; Gobble, Ryan M.; Schneeberger, Stefan

    2014-01-01

    Vascularized composite allotransplantation (VCA) is a novel therapeutic option for treatment of patients suffering from limb loss or severe facial disfigurement. To date, 72 hand and 19 facial transplantations have been performed worldwide. VCA in hand and facial transplantation is a complex procedure requiring a multidisciplinary team approach and extensive surgical planning. Despite good functional outcome, courses after hand and facial transplantation have been complicated by skin rejection. Long-term immunosuppression remains a necessity in VCA for allograft survival. To widen the scope of these quality-of-life-improving procedures, minimization of immunosuppression to limit risks and side effects is needed. PMID:24478387

  9. [Treatment of eye allergies].

    PubMed

    Kari, Osmo; Saari, K Matti

    2012-01-01

    Seasonal atopic conjunctivitis is treated with antihistamines, cromoglycate and short courses of corticosteroids, in severe cases with subcutaneous or sublingual immunotherapy. Chronic conjunctivitis requires year-round treatment with mast cell stabilizers, antihistamines or topical corticosteroids. Long-term treatment of atopic blepharoconjunctivitis consists of tacrolimus or pimecrolimus cream. For atopic keratoconjunctivitis corticosteroid and, if necessary, cyclosporine eye drops are needed. First-line therapy of vernal conjunctivitis involves mast cell stabilizers and, if necessary, corticosteroid eye drops. Treatment of non-allergic eosinophilic conjunctivitis involves mast cell stabilizers, corticosteroid and, if necessary, cyclosporine eye drops. PMID:22428383

  10. Eye-Safe Lidar

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1989-01-01

    Laser infrared radar (lidar) undergoing development harmless to human eyes, consists almost entirely of solid-state components, and offers high range resolution. Operates at wavelength of about 2 micrometers. If radiation from such device strikes eye, almost completely absorbed by cornea without causing damage, even if aimed directly at eye. Continuous-wave light from laser oscillator amplified and modulated for transmission from telescope. Small portion of output of oscillator fed to single-mode fiber coupler, where mixed with return pulses. Intended for remote Doppler measurements of winds and differential-absorption measurements of concentrations of gases in atmosphere.

  11. Versatile impact hand tool

    NASA Technical Reports Server (NTRS)

    Hodil, E. R.

    1968-01-01

    Improved cartridge-actuated impact hand tool includes a common power head and four attachments to punch holes, drive forced entry fasteners, hammer, and shear. The attachments are self-contained and easily fitted to the power head assembly.

  12. Arthritis of the Hand

    MedlinePlus

    ... of hand and wrist arthritis. (Note: The U.S. Food and Drug Administration does not test dietary supplements. These compounds may cause negative interactions with other medications. Always consult your doctor before taking dietary supplements.) ...

  13. Autologous serum eye drops for dry eye

    PubMed Central

    Pan, Qing; Angelina, Adla; Zambrano, Andrea; Marrone, Michael; Stark, Walter J; Heflin, Thomas; Tang, Li; Akpek, Esen K

    2014-01-01

    Background Theoretically, autologous serum eye drops (AS) have a potential advantage over traditional therapies based on the assumption that AS serve not only as a lacrimal substitute to provide lubrication, but also contain other biochemical components mimicking natural tears more closely. The application of AS in dry eye treatment has gained popularity as a second-line therapy in the treatment of dry eye. Published studies on the subject indicate that autologous serum could be an effective treatment for dry eye. Objectives To evaluate the efficacy and safety of AS compared to artificial tears for treating dry eye. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 3), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLD MEDLINE, (January 1950 to April 2013), EMBASE (January 1980 to April 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to April 2013), the meta Register of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We also searched the Science Citation Index Expanded database (September 2013) and reference lists of included studies. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 15 April 2013. Selection criteria We included randomized controlled trials (RCTs) in which AS was compared to artificial tears in the treatment of dry eye in adults. Data collection and analysis Two review authors independently screened all titles and abstracts and assessed full-text articles of potentially eligible trials. Two review authors extracted data and assessed the methodological quality and characteristics of the included trials.We contacted investigators for missing data

  14. Smart Hand For Manipulators

    NASA Astrophysics Data System (ADS)

    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.

  15. Now you see me, now you don’t: evidence that chimpanzees understand the role of the eyes in attention

    PubMed Central

    Hostetter, Autumn B.; Russell, Jamie L.; Freeman, Hani; Hopkins, William D.

    2007-01-01

    Chimpanzees appear to understand something about the attentional states of others; in the present experiment, we investigated whether they understand that the attentional state of a human is based on eye gaze. In all, 116 adult chimpanzees were offered food by an experimenter who engaged in one of the four experimental manipulations: eyes closed, eyes open, hand over eyes, and hand over mouth. The communicative behavior of the chimpanzees was observed. More visible behaviors were produced when the experimenter’s eyes were visible than when the experimenter’s eyes were not visible. More vocalizations were produced when the experimenter’s eyes were closed than when they were open, but there were no differences in other attention getting behaviors. There was no effect of age or rearing history. The results suggest that chimpanzees use the presence of the eyes as a cue that their visual gestures will be effective. PMID:16847659

  16. Diabetic Eye Disease

    MedlinePlus

    ... Health Education Program Diabetic Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Spanish-language ... FAQ Watch out for your vision! Glossary Resources Glaucoma Glaucoma Home How Much Do You Know? What ...

  17. Amblyopia: Lazy Eye Treatment

    MedlinePlus

    ... Choosing Safe Toys this Holiday Dec 02, 2015 Digital Glasses For Lazy Eye Nov 19, 2015 Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About ...

  18. Amblyopia: Lazy Eye Symptoms

    MedlinePlus

    ... Choosing Safe Toys this Holiday Dec 02, 2015 Digital Glasses For Lazy Eye Nov 19, 2015 Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About ...

  19. Amblyopia: Lazy Eye Diagnosis

    MedlinePlus

    ... Choosing Safe Toys this Holiday Dec 02, 2015 Digital Glasses For Lazy Eye Nov 19, 2015 Follow The Academy Professionals: Education Guidelines News Multimedia Public & Patients: Contact Us About ...

  20. What Is Dry Eye?

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  1. Down Syndrome: Eye Problems

    MedlinePlus

    American Association for Pediatric Ophthalmology and Strabismus Home About AAPOS Patient Info Resources Allied Health News & Events Meetings J AAPOS American Association for Pediatric Ophthalmology and Strabismus Eye Terms ...

  2. Fungal Eye Infections

    MedlinePlus

    ... Zoonotic Infectious Disease Division of Foodborne, Waterborne, and Environmental Diseases Mycotic Diseases Branch Fungal Eye Infections Recommend on ... Zoonotic Infectious Disease Division of Foodborne, Waterborne, and Environmental Diseases Mycotic Diseases Branch File Formats Help: How do ...

  3. Dry eye syndrome

    MedlinePlus

    ... particles that have gotten in. A healthy tear film on the eye is necessary for good vision. ... exam Diagnostic staining of the cornea and tear film Measurement of tear film break-up time (TBUT) ...

  4. Using Eye Makeup

    MedlinePlus

    ... 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 ...

  5. Anatomy of the Eye

    MedlinePlus

    ... 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 ...

  6. Melanoma of the eye

    MedlinePlus

    ... modified July 9, 2015. www.cancer.gov/types/eye/hp/intraocular-melanoma-treatment-pdq . Accessed October 7, 2015. Read ... by: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed ...

  7. Eye Injuries in Sports

    MedlinePlus

    ... these injuries can be prevented. Overall, basketball and baseball cause the most eye injuries, followed by water ... involve body contact. Some high-risk sports are baseball, basketball, hockey, football, lacrosse, tennis and other racquet ...

  8. [Straight in the eyes].

    PubMed

    Diop, E; Beylot, V; Berta, C; Dugardin, C; Aigle, L

    2015-01-01

    This case report about a young French soldier hit in the eye by a spitting cobra in the Central African Republic prompts us to review the potential toxicity of this venom to the eyes and the management of this injury. The initial phase is simple to implement, but is often performed badly or not at all because unknown. It is a condition, however, for optimal recovery of the cornea. PMID:26067984

  9. Direct coupling of haptic signals between hands

    PubMed Central

    Dupin, Lucile; Hayward, Vincent; Wexler, Mark

    2015-01-01

    Although motor actions can profoundly affect the perceptual interpretation of sensory inputs, it is not known whether the combination of sensory and movement signals occurs only for sensory surfaces undergoing movement or whether it is a more general phenomenon. In the haptic modality, the independent movement of multiple sensory surfaces poses a challenge to the nervous system when combining the tactile and kinesthetic signals into a coherent percept. When exploring a stationary object, the tactile and kinesthetic signals come from the same hand. Here we probe the internal structure of haptic combination by directing the two signal streams to separate hands: one hand moves but receives no tactile stimulation, while the other hand feels the consequences of the first hand’s movement but remains still. We find that both discrete and continuous tactile and kinesthetic signals are combined as if they came from the same hand. This combination proceeds by direct coupling or transfer of the kinesthetic signal from the moving to the feeling hand, rather than assuming the displacement of a mediating object. The combination of signals is due to perception rather than inference, because a small temporal offset between the signals significantly degrades performance. These results suggest that the brain simplifies the complex coordinate transformation task of remapping sensory inputs to take into account the movements of multiple body parts in haptic perception, and they show that the effects of action are not limited to moving sensors. PMID:25548179

  10. Hands of early primates.

    PubMed

    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

  11. Eye Protection in Educational Institutions.

    ERIC Educational Resources Information Center

    New Jersey State Dept. of Education, Trenton. Div. of Vocational Education.

    Intended to help reduce the number of school eye injuries in New Jersey, this document begins with a brief review of existing legislation regarding eye protection in educational institutions and a list of elements essential in an eye safety program. Second, eye protection equipment is examined in terms of: the advantages of safety spectacles over…

  12. Eye Safety. Mississippi Industrial Arts.

    ERIC Educational Resources Information Center

    Mississippi State Dept. of Education, Jackson. Div. of Vocational and Technical Education.

    This manual is designed to help industrial arts teachers eliminate student eye injuries within industrial arts programs. Presented first is Mississippi eye safety law. Following a discussion of eye protection equipment, illustrations of eye protection devices are provided. Guidelines are set forth for selecting shade numbers for welding filters.…

  13. Learning rational temporal eye movement strategies.

    PubMed

    Hoppe, David; Rothkopf, Constantin A

    2016-07-19

    During active behavior humans redirect their gaze several times every second within the visual environment. Where we look within static images is highly efficient, as quantified by computational models of human gaze shifts in visual search and face recognition tasks. However, when we shift gaze is mostly unknown despite its fundamental importance for survival in a dynamic world. It has been suggested that during naturalistic visuomotor behavior gaze deployment is coordinated with task-relevant events, often predictive of future events, and studies in sportsmen suggest that timing of eye movements is learned. Here we establish that humans efficiently learn to adjust the timing of eye movements in response to environmental regularities when monitoring locations in the visual scene to detect probabilistically occurring events. To detect the events humans adopt strategies that can be understood through a computational model that includes perceptual and acting uncertainties, a minimal processing time, and, crucially, the intrinsic costs of gaze behavior. Thus, subjects traded off event detection rate with behavioral costs of carrying out eye movements. Remarkably, based on this rational bounded actor model the time course of learning the gaze strategies is fully explained by an optimal Bayesian learner with humans' characteristic uncertainty in time estimation, the well-known scalar law of biological timing. Taken together, these findings establish that the human visual system is highly efficient in learning temporal regularities in the environment and that it can use these regularities to control the timing of eye movements to detect behaviorally relevant events. PMID:27382164

  14. AUTOMATIC HAND COUNTER

    DOEpatents

    Mann J.R.; Wainwright, A.E.

    1963-06-11

    An automatic, personnel-operated, alpha-particle hand monitor is described which functions as a qualitative instrument to indicate to the person using it whether his hands are cold'' or hot.'' The monitor is activated by a push button and includes several capacitor-triggered thyratron tubes. Upon release of the push button, the monitor starts the counting of the radiation present on the hands of the person. If the count of the radiation exceeds a predetermined level within a predetermined time, then a capacitor will trigger a first thyratron tube to light a hot'' lamp. If, however, the count is below such level during this time period, another capacitor will fire a second thyratron to light a safe'' lamp. (AEC)

  15. The injured eye

    PubMed Central

    Scott, Robert

    2011-01-01

    Eye injuries come at a high cost to society and are avoidable. Ocular blast injuries can be primary, from the blast wave itself; secondary, from fragments carried by the blast wind; tertiary; due to structural collapse or being thrown against a fixed object; or quaternary, from burns and indirect injuries. Ballistic eye protection significantly reduces the incidence of eye injuries and should be encouraged from an early stage in Military training. Management of an injured eye requires meticulous history taking, evaluation of vision that measures the acuity and if there is a relative pupillary defect as well as careful inspection of the eyes, under anaesthetic if necessary. A lateral canthotomy with cantholysis should be performed immediately if there is a sight-threatening retrobulbar haemorrhage. Systemic antibiotics should be prescribed if there is a suspected penetrating or perforating injury. A ruptured globe should be protected by an eye shield. Primary repair of ruptured globes should be performed in a timely fashion. Secondary procedures will often be required at a later date to achieve sight preservation. A poor initial visual acuity is not a guarantee of a poor final result. The final result can be predicted after approximately 3–4 weeks. Future research in eye injuries attempts to reduce scarring and neuronal damage as well as to promote photoreceptor rescue, using post-transcriptional inhibition of cell death pathways and vaccination to promote neural recovery. Where the sight has been lost sensory substitution of a picture from a spectacle mounted video camera to the touch receptors of the tongue can be used to achieve appreciation of the outside world. PMID:21149360

  16. [Skin and hand disinfection].

    PubMed

    Mathis, U

    1991-04-01

    In modern medicine, hygiene has become an issue of ever increasing importance. Disinfection of hands is crucial, since hands are the main vector of bacteria. Successful disinfection depends not only on the appropriate choice of an active agent, but equally so on proper techniques and skin care. The spectre and the time profile of activity as well as the skin-protecting properties of the chosen disinfectant must be known. Basic knowledge of disinfection is necessary for a rational interpretation of the information given in the glossy printed material of advertisement. PMID:1858061

  17. Portable hand hold device

    NASA Technical Reports Server (NTRS)

    Redmon, Jr., John W. (Inventor); McQueen, Donald H. (Inventor); Sanders, Fred G. (Inventor)

    1990-01-01

    A hand hold device (A) includes a housing (10) having a hand hold (14) and clamping brackets (32,34) for grasping and handling an object. A drive includes drive lever (23), spur gear (22), and rack gears (24,26) carried on rods (24a, 26a) for moving the clamping brackets. A lock includes ratchet gear (40) and pawl (42) biased between lock and unlock positions by a cantilever spring (46,48) and moved by handle (54). Compliant grip pads (32b, 34b) provide compliance to lock, unlock, and hold an object between the clamp brackets.

  18. [Hands cutaneous exam].

    PubMed

    Lorette, Gérard; Samimi, Mahtab

    2013-12-01

    There are four different areas to consider: palms, back of the hands, fingers, periungual folds (and nails). Palmoplantar keratodermas are a group of inherited or acquired disorders. Dysidrosis is a peculiar form of eczema on the palms and lateral aspects of the fingers. SAPHO syndrome (Synovitis - Acne - Pustulosis - Hyperostosis - Osteomyelitis) presents pustules on palms. Photo-ageing is frequently noticed on the back of the hands. Paraneoplastic acrokeratosis (Bazex syndrome) affects the nose, ears, and periungual folds of fingers and toes. Spontaneous blue finger syndrome can be a benign process that resolves rapidly. PMID:24157184

  19. Binocular eye movements in health and disease

    NASA Astrophysics Data System (ADS)

    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.

  20. Eye Movements Reveal How Task Difficulty Moulds Visual Search

    ERIC Educational Resources Information Center

    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…

  1. Horizontal Saccadic Eye Movements Enhance the Retrieval of Landmark Shape and Location Information

    ERIC Educational Resources Information Center

    Brunye, Tad T.; Mahoney, Caroline R.; Augustyn, Jason S.; Taylor, Holly A.

    2009-01-01

    Recent work has demonstrated that horizontal saccadic eye movements enhance verbal episodic memory retrieval, particularly in strongly right-handed individuals. The present experiments test three primary assumptions derived from this research. First, horizontal eye movements should facilitate episodic memory for both verbal and non-verbal…

  2. Three-Fingered Robot Hand

    NASA Technical Reports Server (NTRS)

    Ruoff, C. F.; Salisbury, J. K.

    1984-01-01

    Mechanical joints and tendons resemble human hand. Robot hand has three "human-like" fingers. "Thumb" at top. Rounded tips of fingers covered with resilient material provides high friction for griping. Hand potential as prosthesis for humans.

  3. American Association for Hand Surgery

    MedlinePlus

    ... for Wrist Injuries: A Brief Literature Update HAND Journal HAND , the official Journal of AAHS HAND is the official peer-reviewed Journal of AAHS, featuring articles written by clinicians worldwide ...

  4. Hands-on Humidity.

    ERIC Educational Resources Information Center

    Pankiewicz, Philip R.

    1992-01-01

    Presents five hands-on activities that allow students to detect, measure, reduce, and eliminate moisture. Students make a humidity detector and a hygrometer, examine the effects of moisture on different substances, calculate the percent of water in a given food, and examine the absorption potential of different desiccants. (MDH)

  5. Learning "Hands On."

    ERIC Educational Resources Information Center

    Ritter, Janice T.

    2001-01-01

    Discusses a computer teacher's incorporation of hand-held computer technology into her third- and fifth-grade students' study of acid rain. The project successfully brought two grade levels together for cross-grade research, provided an opportunity for classroom teachers and technology specialists to work collaboratively, and enhanced students'…

  6. Mechanical cornpicker hand injuries.

    PubMed

    Momcilović, Dragan; Prokes, Bela; Janjić, Zlata

    2005-01-01

    Mechanical cornpicker hand injuries are not frequent in comparison to general hand trauma, but they have a specific mechanism of occurrence and are very severe. This investigation included 221 hand injuries. The sex distribution shows a general male dominance (85.25%) in their active age (84.44%). These are, seasonal injuries mostly occurring in October (75.11%). By type of injuries, mutilating crush injuries are most frequent (64.25%). After completing the treatment, in most cases the functional result were estimated as bad (50.68%). Data concerning education and trainig for operating agricultural machines (96.38%--patients without training) and carrying out safety measures (63.35% of injured patients did not apply any protection measures) are devastating. The number of these injuries, as well as consequent permanent disabilities, may be considerably reduced by preventive measures, inclulding public health services and media. Use of contempoarary agricultural machinery, as well as obligatory training for operating these machines and application of protective measures, may also reduce the incidence of hand injuries during corn picking. PMID:16526250

  7. Hands On Earth Science.

    ERIC Educational Resources Information Center

    Weisgarber, Sherry L.; Van Doren, Lisa; Hackathorn, Merrianne; Hannibal, Joseph T.; Hansgen, Richard

    This publication is a collection of 13 hands-on activities that focus on earth science-related activities and involve students in learning about growing crystals, tectonics, fossils, rock and minerals, modeling Ohio geology, geologic time, determining true north, and constructing scale-models of the Earth-moon system. Each activity contains…

  8. A Helping Hand.

    ERIC Educational Resources Information Center

    Wilke, Arnie

    2003-01-01

    Describes steps schools can take to provide cleaner and safer washrooms. Emphasizes hand-washing to battle germs and asserts that creating a comfortable and user-friendly washroom is a critical and often overlooked aspect for encouraging better hygiene habits. (EV)

  9. Electrically powered hand tool

    DOEpatents

    Myers, Kurt S.; Reed, Teddy R.

    2007-01-16

    An electrically powered hand tool is described and which includes a three phase electrical motor having a plurality of poles; an electrical motor drive electrically coupled with the three phase electrical motor; and a source of electrical power which is converted to greater than about 208 volts three-phase and which is electrically coupled with the electrical motor drive.

  10. Hands-On Hydrology

    ERIC Educational Resources Information Center

    Mathews, Catherine E.; Monroe, Louise Nelson

    2004-01-01

    A professional school and university collaboration enables elementary students and their teachers to explore hydrology concepts and realize the beneficial functions of wetlands. Hands-on experiences involve young students in determining water quality at field sites after laying the groundwork with activities related to the hydrologic cycle,…

  11. Hands-on Herps.

    ERIC Educational Resources Information Center

    Science Activities, 1987

    1987-01-01

    Presents a hands-on activity to help primary, intermediate, and advanced students learn about and compare the general characteristics of reptiles and amphibians. Suggests "herp stations" to provide experiences. Details materials, background and procedures necessary for using this activity. (CW)

  12. Rotationally Actuated Prosthetic Hand

    NASA Technical Reports Server (NTRS)

    Norton, William E.; Belcher, Jewell G., Jr.; Carden, James R.; Vest, Thomas W.

    1991-01-01

    Prosthetic hand attached to end of remaining part of forearm and to upper arm just above elbow. Pincerlike fingers pushed apart to degree depending on rotation of forearm. Simpler in design, simpler to operate, weighs less, and takes up less space.

  13. Sight-reading of violinists: eye movements anticipate the musical flow.

    PubMed

    Wurtz, Pascal; Mueri, René M; Wiesendanger, Mario

    2009-04-01

    When sight-reading a piece of music the eyes constantly scan the score slightly ahead of music execution. This separation between reading and acting is commonly termed eye-hand span and can be expressed in two ways: as anticipation in notes or in time. Previous research, predominantly in piano players, found skill-dependent differences of eye-hand span. To date no study has explored visual anticipation in violinists. The present study investigated how structural properties of a piece of music affect the eye-hand span in a group of violinists. To this end eye movements and bow reversals were recorded synchronously while musicians sight-read a piece of music. The results suggest that structural differences of the score are reflected in the eye-hand span in a way similar to skill level. Specifically, the piece with higher complexity was associated with lower anticipation in notes, longer fixation duration and a tendency for more regressive fixations. Anticipation in time, however, remained the same (approximately 1 s) independently of the score played but was correlated with playing tempo. We conclude that the eye-hand span is not only influenced by the experience of the musician, but also by the structure of the score to be played. PMID:19205680

  14. COMPU-EYE: a high resolution computational compound eye.

    PubMed

    Lee, Woong-Bi; Jang, Hwanchol; Park, Sangjun; Song, Young Min; Lee, Heung-No

    2016-02-01

    In nature, the compound eyes of arthropods have evolved towards a wide field of view (FOV), infinite depth of field and fast motion detection. However, compound eyes have inferior resolution when compared with the camera-type eyes of vertebrates, owing to inherent structural constraints such as the optical performance and the number of ommatidia. For resolution improvements, in this paper, we propose COMPUtational compound EYE (COMPU-EYE), a new design that increases acceptance angles and uses a modern digital signal processing (DSP) technique. We demonstrate that the proposed COMPU-EYE provides at least a four-fold improvement in resolution. PMID:26906778

  15. Comparison of surgical hand scrub and alcohol surgical hand rub on reducing hand microbial burden.

    PubMed

    Ghorbani, Azam; Shahrokhi, Akram; Soltani, Zahra; Molapour, Azam; Shafikhani, Mahin

    2012-02-01

    This study was performed to compare the effects of two hand decontamination methods on the microbial burden of operating room staff hands. The surgical hand washing methods compared were a traditional surgical hand scrub using a povidone iodine solution, and a social wash using a liquid non-antibacterial soap followed by the application of an alcoholic hand rub. PMID:22724306

  16. Artificial neural superposition eye.

    PubMed

    Brückner, Andreas; Duparré, Jacques; Dannberg, Peter; Bräuer, Andreas; Tünnermann, Andreas

    2007-09-17

    We propose an ultra-thin imaging system which is based on the neural superposition compound eye of insects. Multiple light sensitive pixels in the footprint of each lenslet of this multi-channel configuration enable the parallel imaging of the individual object points. Together with the digital superposition of related signals this multiple sampling enables advanced functionalities for artificial compound eyes. Using this technique, color imaging and a circumvention for the trade-off between resolution and sensitivity of ultra-compact camera devices have been demonstrated in this article. The optical design and layout of such a system is discussed in detail. Experimental results are shown which indicate the attractiveness of microoptical artificial compound eyes for applications in the field of machine vision, surveillance or automotive imaging. PMID:19547555

  17. Intelligent, self-contained robotic hand

    DOEpatents

    Krutik, Vitaliy; Doo, Burt; Townsend, William T.; Hauptman, Traveler; Crowell, Adam; Zenowich, Brian; Lawson, John

    2007-01-30

    A robotic device has a base and at least one finger having at least two links that are connected in series on rotary joints with at least two degrees of freedom. A brushless motor and an associated controller are located at each joint to produce a rotational movement of a link. Wires for electrical power and communication serially connect the controllers in a distributed control network. A network operating controller coordinates the operation of the network, including power distribution. At least one, but more typically two to five, wires interconnect all the controllers through one or more joints. Motor sensors and external world sensors monitor operating parameters of the robotic hand. The electrical signal output of the sensors can be input anywhere on the distributed control network. V-grooves on the robotic hand locate objects precisely and assist in gripping. The hand is sealed, immersible and has electrical connections through the rotary joints for anodizing in a single dunk without masking. In various forms, this intelligent, self-contained, dexterous hand, or combinations of such hands, can perform a wide variety of object gripping and manipulating tasks, as well as locomotion and combinations of locomotion and gripping.

  18. Eye movements and their functions in everyday tasks

    PubMed Central

    Foulsham, T

    2015-01-01

    Human saccades and fixations have numerous functions in complex everyday tasks, which have sometimes been neglected in simple experimental situations. In this review I describe some of the characteristics of eye movement behaviour during real-world interactions with objects, while walking in natural environments and while holding a conversation. When performing real-world actions and walking around the world, we fixate relevant features at critical time points during the task. The eye movements between these fixations are planned and coordinated alongside head and body movements, often occurring a short time before the corresponding action. In social interactions, eye movements are both a mechanism for taking in information (for example, when looking at someone's face or following their gaze) and for signalling one's attention to another person. Thus eye movements are specific to a particular task context and subject to high-level planning and control during everyday actions. PMID:25397783

  19. Photorefraction of the Eye

    NASA Astrophysics Data System (ADS)

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-02-01

    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 principles underlying the method for eccentric photorefraction and describe how students can perform it using current digital cameras. Our purpose is not to diagnose refractive errors reliably, but to use devices popular among young people that, in combination with an important ophthalmic context, may be successful in improving students' interest for learning optical concepts.

  20. Transforming geocentric cartesian coordinates to geodetic coordinates by using differential search algorithm

    NASA Astrophysics Data System (ADS)

    Civicioglu, Pinar

    2012-09-01

    In order to solve numerous practical navigational, geodetic and astro-geodetic problems, it is necessary to transform geocentric cartesian coordinates into geodetic coordinates or vice versa. It is very easy to solve the problem of transforming geodetic coordinates into geocentric cartesian coordinates. On the other hand, it is rather difficult to solve the problem of transforming geocentric cartesian coordinates into geodetic coordinates as it is very hard to define a mathematical relationship between the geodetic latitude (φ) and the geocentric cartesian coordinates (X, Y, Z). In this paper, a new algorithm, the Differential Search Algorithm (DS), is presented to solve the problem of transforming the geocentric cartesian coordinates into geodetic coordinates and its performance is compared with the performances of the classical methods (i.e., Borkowski, 1989; Bowring, 1976; Fukushima, 2006; Heikkinen, 1982; Jones, 2002; Zhang, 2005; Borkowski, 1987; Shu, 2010 and Lin, 1995) and Computational-Intelligence algorithms (i.e., ABC, JDE, JADE, SADE, EPSDE, GSA, PSO2011, and CMA-ES). The statistical tests realized for the comparison of performances indicate that the problem-solving success of DS algorithm in transforming the geocentric cartesian coordinates into geodetic coordinates is higher than those of all classical methods and Computational-Intelligence algorithms used in this paper.

  1. Flight deck crew coordination indices of workload and situation awareness in terminal operations

    NASA Astrophysics Data System (ADS)

    Ellis, Kyle Kent Edward

    Crew coordination in the context of aviation is a specifically choreographed set of tasks performed by each pilot, defined for each phase of flight. Based on the constructs of effective Crew Resource Management and SOPs for each phase of flight, a shared understanding of crew workload and task responsibility is considered representative of well-coordinated crews. Nominal behavior is therefore defined by SOPs and CRM theory, detectable through pilot eye-scan. This research investigates the relationship between the eye-scan exhibited by each pilot and the level of coordination between crewmembers. Crew coordination was evaluated based on each pilot's understanding of the other crewmember's workload. By contrasting each pilot's workload-understanding, crew coordination was measured as the summed absolute difference of each pilot's understanding of the other crewmember's reported workload, resulting in a crew coordination index. The crew coordination index rates crew coordination on a scale ranging across Excellent, Good, Fair and Poor. Eye-scan behavior metrics were found to reliably identify a reduction in crew coordination. Additionally, crew coordination was successfully characterized by eye-scan behavior data using machine learning classification methods. Identifying eye-scan behaviors on the flight deck indicative of reduced crew coordination can be used to inform training programs and design enhanced avionics that improve the overall coordination between the crewmembers and the flight deck interface. Additionally, characterization of crew coordination can be used to develop methods to increase shared situation awareness and crew coordination to reduce operational and flight technical errors. Ultimately, the ability to reduce operational and flight technical errors made by pilot crews improves the safety of aviation.

  2. Head-mounted computer interface based on eye tracking

    NASA Astrophysics Data System (ADS)

    Schroeder, William E.

    1993-10-01

    A head-mounted computer interface using eye-tracking as a `pointer' was demonstrated at the Third Annual Weapons Technology Review and Training Exposition at San Diego in January 1992, and is under further development for military and civilian applications. in this interface, the computer interprets eye gaze direction just as it would input from a mouse or trackball. This technology makes possible computer-human interaction with many ideal aspects: complete portability, hands-free operation, silent, secure operation anywhere and any time. Commercial systems using control inputs from the tracked eye are available and effective within their limits, but size, weight, and cost have been barriers to wider use. This paper describes the latest head-mounted eye tracking display (HETD) development prototype. We are exploring the technological limits of current and near-term lighting, detector, and lens technology to project the feasibility of this device.

  3. Do Muscles Matter for Coordinated Action?

    ERIC Educational Resources Information Center

    Mechsner, Franz; Knoblich, Giinther

    2004-01-01

    This article investigates coordination stability when 2 fingers of each hand periodically tap together. The main question concerns the functional origin of the symmetry tendency, which has widely been conceived as a bias toward coactivation of homologous fingers and homologous muscular portions. In Experiment 1, the symmetry tendency was…

  4. Glaucoma: Eye-to-Eye with Dr. Rachel Bishop

    MedlinePlus

    ... of this page please turn JavaScript on. Feature: Glaucoma Eye-to-Eye with Dr. Rachel Bishop Past ... nerves are pale and cupped—signs of advanced glaucoma. Yet the patient wasn't aware of any ...

  5. Eye evolution: two eyes can be better than one.

    PubMed

    Foster, Kenneth W

    2009-03-10

    The development of our eyes is owed in part to ancestral structures which functioned in phototaxis. With the origin of bilateral annelid larva, two eyes co-evolved with neurons to improve phototaxis performance. PMID:19278637

  6. Combination hand rejuvenation procedures.

    PubMed

    Shamban, Ava T

    2009-01-01

    Although the hands age at the same rate as the face, the aging process differs and requires a combination treatment approach for optimal rejuvenation. Photoaging causes epidermal changes such as lentigines, actinic keratoses, fine wrinkles, and crepe-like textural change. Thinning of the dermis and subcutaneous fat occurs as a result of both ultraviolet light exposure and intrinsic aging. This process can lead to a skeletal appearance of the hands, with prominent veins and bulging tendons. The combination approach addresses all of these issues, employing lasers, intense pulsed light devices, fractional devices, fillers, peels, vein sclerotherapy, and an effective at-home skin care program as indicated for individual needs and concerns. PMID:19825471

  7. Tropical Diabetic Hand Syndrome

    PubMed Central

    Okpara, TC; Ezeala-Adikaibe, BA; Omire, O; Nwonye, E; Maluze, J

    2015-01-01

    Any adult with diabetes in the tropics with hand cellulitis, infection and gangrene qualifies for tropical diabetic hand syndrome (TDHS). We reviewed a 39-year-old woman with a 3-week history of swelling of the left index finger following an insect bite. The swelling progressively increased in size, was very painful, and extended to the palm. There was no history or symptoms suggestive of chronic complications of diabetes. Random blood sugar on presentation was above 600 mg/dl using a glucometer. Examination revealed an edematous left palm draining pus from multiple sinuses, necrotic and gangrenous left index finger extending down to just above the thenar eminence. A diagnosis of TDHS in a patient with hyperosmolar state was made. She was managed accordingly and subsequently underwent aggressive debridement and desloughing. Two fingers were amputated and the wound was allowed to heal by secondary intention. PMID:27057390

  8. Tropical Diabetic Hand Syndrome.

    PubMed

    Okpara, T C; Ezeala-Adikaibe, B A; Omire, O; Nwonye, E; Maluze, J

    2015-01-01

    Any adult with diabetes in the tropics with hand cellulitis, infection and gangrene qualifies for tropical diabetic hand syndrome (TDHS). We reviewed a 39-year-old woman with a 3-week history of swelling of the left index finger following an insect bite. The swelling progressively increased in size, was very painful, and extended to the palm. There was no history or symptoms suggestive of chronic complications of diabetes. Random blood sugar on presentation was above 600 mg/dl using a glucometer. Examination revealed an edematous left palm draining pus from multiple sinuses, necrotic and gangrenous left index finger extending down to just above the thenar eminence. A diagnosis of TDHS in a patient with hyperosmolar state was made. She was managed accordingly and subsequently underwent aggressive debridement and desloughing. Two fingers were amputated and the wound was allowed to heal by secondary intention. PMID:27057390

  9. Alien Hand Syndrome.

    PubMed

    Hassan, Anhar; Josephs, Keith A

    2016-08-01

    Alien hand syndrome (AHS) is a rare disorder of involuntary limb movement together with a sense of loss of limb ownership. It most commonly affects the hand, but can occur in the leg. The anterior (frontal, callosal) and posterior variants are recognized, with distinguishing clinical features and anatomical lesions. Initial descriptions were attributed to stroke and neurosurgical operations, but neurodegenerative causes are now recognized as most common. Structural and functional imaging and clinical studies have implicated the supplementary motor area, pre-supplementary motor area, and their network connections in the frontal variant of AHS, and the inferior parietal lobule and connections in the posterior variant. Several theories are proposed to explain the pathophysiology. Herein, we review the literature to update advances in the understanding of the classification, pathophysiology, etiology, and treatment of AHS. PMID:27315251

  10. Hand tools: A compilation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A selection of new hand tools, modifications of existing tools, and techniques developed in the course of NASA research and development projects are presented. The items are presented in two sections: tools for cable and connector applications, and tools for welding applications. Safety is emphasized, together with ease of operation and use in restricted areas or hazardous environments. The discussions are directed primarily toward the technician engaged in assembly or maintenance of mechanical or electrical equipment.

  11. Pediatric hand treadmill injuries.

    PubMed

    Banever, Gregory T; Moriarty, Kevin P; Sachs, Barry F; Courtney, Richard A; Konefal, Stanley H; Barbeau, Lori

    2003-07-01

    The great popularity of physical fitness in modern society has brought many pieces of exercise equipment into our homes for convenience and privacy. This trend has come with an increasing rate of injuries to children who curiously touch moving parts, including treadmill belts. Experience with a recent series of treadmill contact burns to children's hands is described in this article. A retrospective chart review at a tertiary referral center from June 1998 until June 2001 found six children sustaining hand burns from treadmills. The patients' ages at presentation ranged from 15 to 45 months (average of 31 months, three boys and three girls). All injuries occurred in the home while a parent was using the treadmill. Burns involved the palmar aspect of the hand, mostly confined to the fingers, and the severity ranged from partialto full-thickness burns. All patients were initially managed with collagenase and bacitracin zinc/polymyxin B powder dressings to second- and third-degree burns, along with splinting and range-of-motion exercises. Two patients required skin grafting at 2 weeks and 2 months for full-thickness tissue loss and tight joint contracture, respectively. At an average follow-up of 12 months, all patients had full range of motion and no physical limitation. The rate of children injured by exercise equipment is expected to increase. Friction burns to the hands remain a concern, although early recognition and appropriate management are associated with excellent functional outcomes. Protective modification of exercise machines seems to be the best approach to eliminating these injuries. PMID:12867861

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

    ERIC Educational Resources Information Center

    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…

  13. Artificial dexterous hand

    NASA Technical Reports Server (NTRS)

    Lee, Sukhan (Inventor)

    1990-01-01

    An artificial dexterous hand is provided for grasping and manipulating objects. The hand includes left and right thumbs that are operatively connected to an engagement assembly which causes movement of the left and right thumbs. The left thumb has a left thumb base and is movable about three separate first left thumb axes which run through the left thumb base. Correspondingly, the right thumb has a right thumb base and is movable about three separate first right thumb axes which run through the right thumb base. The engagement assembly has a gear assembly which is operatively connected to a motor assembly. Upon actuation by the motor assembly, the gear assembly causes movement of the left and right thumbs about the first left thumb axes and first right thumb axes respectively. The hand can also have a center finger which is operatively connected to the engagement assembly and which is interposed between the left and right thumbs. The finger has a finger base and is movable about two separate first finger axes running through the finger base. Therefore, upon actuation by the motor assembly, the gear assembly will also cause movement of the finger about the first finger axes.

  14. Compact Dexterous Robotic Hand

    NASA Technical Reports Server (NTRS)

    Lovchik, Christopher Scott (Inventor); Diftler, Myron A. (Inventor)

    2001-01-01

    A compact robotic hand includes a palm housing, a wrist section, and a forearm section. The palm housing supports a plurality of fingers and one or more movable palm members that cooperate with the fingers to grasp and/or release an object. Each flexible finger comprises a plurality of hingedly connected segments, including a proximal segment pivotally connected to the palm housing. The proximal finger segment includes at least one groove defining first and second cam surfaces for engagement with a cable. A plurality of lead screw assemblies each carried by the palm housing are supplied with power from a flexible shaft rotated by an actuator and output linear motion to a cable move a finger. The cable is secured within a respective groove and enables each finger to move between an opened and closed position. A decoupling assembly pivotally connected to a proximal finger segment enables a cable connected thereto to control movement of an intermediate and distal finger segment independent of movement of the proximal finger segment. The dexterous robotic hand closely resembles the function of a human hand yet is light weight and capable of grasping both heavy and light objects with a high degree of precision.

  15. Saccadic Adaptation Is Associated with Starting Eye Position

    PubMed Central

    Gremmler, Svenja; Lappe, Markus

    2016-01-01

    Saccadic adaptation is the motor learning process that keeps saccade amplitudes on target. This process is eye position specific: amplitude adaptation that is induced for a saccade at one particular location in the visual field transfers incompletely to saccades at other locations. In our current study, we investigated wether this eye position signal corresponds to the initial or to the final eye position of the saccade. Each case would have different implications on the mechanisms of adaptation. The initial eye position is not directly available, when the adaptation driving post saccadic error signal is received. On the other hand the final eye position signal is not available, when the motor command for the saccade is calculated. In six human subjects we adapted a saccade of 15 degree amplitude that started at a constant position. We then measured the transfer of adaptation to test saccades of 10 and 20 degree amplitude. In each case we compared test saccades that matched the start position of the adapted saccade to those that matched the target of the adapted saccade. We found significantly more transfer of adaptation to test saccades with the same start position than to test saccades with the same target position. The results indicate that saccadic adaptation is specific to the initial eye position. This is consistent with a previously proposed effect of gain field modulated input from areas like the frontal eye field, the lateral intraparietal area and the superior colliculus into the cerebellar adaptation circuitry. PMID:27445762

  16. Pursuit Eye Movements

    NASA Technical Reports Server (NTRS)

    Krauzlis, Rich; Stone, Leland; Null, Cynthia H. (Technical Monitor)

    1998-01-01

    When viewing objects, primates use a combination of saccadic and pursuit eye movements to stabilize the retinal image of the object of regard within the high-acuity region near the fovea. Although these movements involve widespread regions of the nervous system, they mix seamlessly in normal behavior. Saccades are discrete movements that quickly direct the eyes toward a visual target, thereby translating the image of the target from an eccentric retinal location to the fovea. In contrast, pursuit is a continuous movement that slowly rotates the eyes to compensate for the motion of the visual target, minimizing the blur that can compromise visual acuity. While other mammalian species can generate smooth optokinetic eye movements - which track the motion of the entire visual surround - only primates can smoothly pursue a single small element within a complex visual scene, regardless of the motion elsewhere on the retina. This ability likely reflects the greater ability of primates to segment the visual scene, to identify individual visual objects, and to select a target of interest.

  17. Through Our Eyes

    ERIC Educational Resources Information Center

    Narva, Sara

    2009-01-01

    Through Our Eyes was a multimedia performance created in collaboration with the author's five modern dance students. Through video, sound, and dance, the piece shows some ways race has affected their lives. The author did not set out at the beginning of the semester to make this project in her dance class. It was born out of a hard conversation,…

  18. The Eyes Have It.

    ERIC Educational Resources Information Center

    Walsh, Janet

    1982-01-01

    Discusses the health hazards of working with the visual display systems of computers, in particular the eye problems associated with long-term use of video display terminals. Excerpts from and ordering information for the National Institute for Occupational Safety and Health report on such hazards are included. (JJD)

  19. The Eyes Have It

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA'S Ames Research Center contracted with SRI international to contract a device that would be able to anticipate, track, and monitor involuntary ocular movement horizontally, vertically, and with respect to depth-of-field. This development helped research institutions to understand the eye. The Eyetracker, manufactured and distributed by Forward Optical Technologies, Inc. is now used in the clinical/medical field.

  20. Through Students' Eyes.

    ERIC Educational Resources Information Center

    McLean-Donaldson, Karen B.

    1994-01-01

    Identifies how students perceive racism and its effects on student learning and whether antiracist/multicultural arts (ARMA) curricula can empower students to address racism in schools. Results show racism, through students' eyes, damages learning, attitudes, and behavior. ARMA positively effected students' ability to confront racism within their…

  1. Administering Eye Medications.

    ERIC Educational Resources Information Center

    Morris, Sara; Michael, Nancy, Ed.

    This module on administering eye medications is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. A brief discussion follows of…

  2. Red or uncomfortable eye.

    PubMed Central

    Davey, C.; Hurwitz, B.

    1992-01-01

    1. A red, uncomfortable eye may be accompanied by other symptoms such as blurred, decreased, or double vision, haloes, photophobia, pain or discharge. 2. A careful history and brief systematic examination will sort out most problems. 3. Examine eyelids, the conjunctivae and corneas. Checking visual acuity is often important. 4. The most common underlying causes can usually be managed within general practice, though a few patients will require urgent eye assessment, or routine referral to ophthalmic outpatients. 5. The following are typical eye problems which require urgent referral: History of pain as opposed to discomfort, Trauma including foreign bodies, chemicals and suspected penetrating injury, Unexplained drop in visual acuity of two lines or more in a painful eye. Specific conditions: preseptal cellulitis, herpes simplex ulcer, scleritis, orbital cellulitis, herpes zoster, bacterial corneal ulcer, dacryocystitis. 6. The following are typical problems which may require routine referral: Persistence of the problem not relieved by simple measures, Recurrent disorders of uncertain diagnosis, Eyelid swelling such as chalazion, cysts, basal cell carcinoma, Gradual loss of vision, for example cataract, macular degeneration. PMID:1345157

  3. Diabetes - eye care

    MedlinePlus

    ... blurred vision is caused by having too much sugar and water in the lens of the eye, which is in front of the retina. Control your blood pressure . Blood pressure less than 130/80 is a ... sugar - self-care Diabetes - preventing heart attack and stroke ...

  4. Eye of the Beholder

    ERIC Educational Resources Information Center

    Rogers, Michael

    2010-01-01

    Art, like beauty, as the adage goes, is in the eye of the beholder. Art also is a living, breathing thing that evolves over time, so what is considered "art" is ever changing--how many of the great artists whose works today sell for fortunes were failures during their lifetime? The 20th century unknowingly gave birth to new variations of art that…

  5. Eyes for Learning

    ERIC Educational Resources Information Center

    Orfield, Antonia

    2008-01-01

    Vision is the dominant sense, and the eyes are connected with almost every other part of the brain. If the vision system is poorly developed, children trying to learn suffer. Without good up close vision, students are handicapped even if no one knows or suspects it--they may not even know it themselves. Students do not know that the way they see…

  6. Common eye emergencies.

    PubMed

    Gelston, Christopher D

    2013-10-15

    Ocular emergencies such as retinal detachments, mechanical globe injuries, and chemical injuries can cause permanent vision loss if they are not recognized and treated promptly. Family physicians should be familiar with the signs and symptoms associated with each condition, and be able to perform a basic eye examination to assess the situation. The assessment includes measurement of visual acuity, pupillary examination, visual field testing, slit lamp or penlight examination of the anterior segment of the eye, and direct funduscopic examination. Patients with symptomatic floaters and flashing lights require a dilated fundoscopic examination and prompt referral to an ophthalmologist for evaluation of a retinal tear or detachment. A globe laceration or rupture should be suspected in patients with a recent history of trauma from a blunt or penetrating object. Prophylactic oral antibiotics can be administered after a globe injury to prevent endophthalmitis, and the eye should be covered with a metal shield until evaluation by an ophthalmologist. Chemical injuries require immediate irrigation of the eye to neutralize the pH of the ocular surface. PMID:24364572

  7. Simple Solutions for Dry Eye

    MedlinePlus

    ... are more concentrated in the tear film of dry eye patients. In hot weather, sleep with the windows shut and keep cool with air conditioning. • Dry eye patients often develop or aggravate allergies. An ...

  8. Infographic on the Aging Eye

    MedlinePlus

    ... retina. Dry eye Low vision Damage to the optic nerve. Eyes do not make enough tears. Difficulty ... retina that can be seen through undilated pupil. OPTIC NERVE RAY OF LIGHT PUPIL RETINA Portion of ...

  9. Recognizing and Treating Eye Injuries

    MedlinePlus

    ... and seek medical attention. In case of a chemical burn to the eye: Immediately flush the eye ... Academy Jobs at the Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For ...

  10. Medicare Benefits and Your Eyes

    MedlinePlus

    ... Eye Health Report Reports and External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy Eyes Education Series Online Training and Certification Patient Education Materials ...

  11. Eye Movements in Strategic Choice

    PubMed Central

    Gächter, Simon; Noguchi, Takao; Mullett, Timothy L.

    2015-01-01

    Abstract In risky and other multiattribute choices, the process of choosing is well described by random walk or drift diffusion models in which evidence is accumulated over time to threshold. In strategic choices, level‐k and cognitive hierarchy models have been offered as accounts of the choice process, in which people simulate the choice processes of their opponents or partners. We recorded the eye movements in 2 × 2 symmetric games including dominance‐solvable games like prisoner's dilemma and asymmetric coordination games like stag hunt and hawk–dove. The evidence was most consistent with the accumulation of payoff differences over time: we found longer duration choices with more fixations when payoffs differences were more finely balanced, an emerging bias to gaze more at the payoffs for the action ultimately chosen, and that a simple count of transitions between payoffs—whether or not the comparison is strategically informative—was strongly associated with the final choice. The accumulator models do account for these strategic choice process measures, but the level‐k and cognitive hierarchy models do not. © 2015 The Authors. Journal of Behavioral Decision Making published by John Wiley & Sons Ltd.

  12. Categorical and Coordinate Relations in Faces, or Fechner's Law and Face Space Instead?

    ERIC Educational Resources Information Center

    McKone, Elinor; Aitkin, Alex; Edwards, Mark

    2005-01-01

    E. E. Cooper and T. J. Wojan (2000) applied the categorical-coordinate relations distinction to faces on the basis of a finding that two-eyes-up versus one-eye-up distortions had opposite effects in between-class (face normality) and within-class (face identity) tasks. However, Cooper and Wojan failed to match amount of metric change between their…

  13. Eye Tracking Detects Disconjugate Eye Movements Associated with Structural Traumatic Brain Injury and Concussion

    PubMed Central

    Ritlop, Robert; Reyes, Marleen; Nehrbass, Elena; Li, Meng; Lamm, Elizabeth; Schneider, Julia; Shimunov, David; Sava, Maria; Kolecki, Radek; Burris, Paige; Altomare, Lindsey; Mehmood, Talha; Smith, Theodore; Huang, Jason H.; McStay, Christopher; Todd, S. Rob; Qian, Meng; Kondziolka, Douglas; Wall, Stephen; Huang, Paul

    2015-01-01

    Abstract Disconjugate eye movements have been associated with traumatic brain injury since ancient times. Ocular motility dysfunction may be present in up to 90% of patients with concussion or blast injury. We developed an algorithm for eye tracking in which the Cartesian coordinates of the right and left pupils are tracked over 200 sec and compared to each other as a subject watches a short film clip moving inside an aperture on a computer screen. We prospectively eye tracked 64 normal healthy noninjured control subjects and compared findings to 75 trauma subjects with either a positive head computed tomography (CT) scan (n=13), negative head CT (n=39), or nonhead injury (n=23) to determine whether eye tracking would reveal the disconjugate gaze associated with both structural brain injury and concussion. Tracking metrics were then correlated to the clinical concussion measure Sport Concussion Assessment Tool 3 (SCAT3) in trauma patients. Five out of five measures of horizontal disconjugacy were increased in positive and negative head CT patients relative to noninjured control subjects. Only one of five vertical disconjugacy measures was significantly increased in brain-injured patients relative to controls. Linear regression analysis of all 75 trauma patients demonstrated that three metrics for horizontal disconjugacy negatively correlated with SCAT3 symptom severity score and positively correlated with total Standardized Assessment of Concussion score. Abnormal eye-tracking metrics improved over time toward baseline in brain-injured subjects observed in follow-up. Eye tracking may help quantify the severity of ocular motility disruption associated with concussion and structural brain injury. PMID:25582436

  14. Experiments on a Model Eye

    ERIC Educational Resources Information Center

    Arell, Antti; Kolari, Samuli

    1978-01-01

    Explains a laboratory experiment dealing with the optical features of the human eye. Shows how to measure the magnification of the retina and the refractive anomaly of the eye could be used to measure the refractive power of the observer's eye. (GA)

  15. How the Human Eye Focuses.

    ERIC Educational Resources Information Center

    Koretz, Jane F.; Handelman, George H.

    1988-01-01

    Describes the decline in people's ability to focus their eyes as their age increases. Discusses probable causes of this effect including changes in the eye's geometry and biochemistry. Diagrammatically illustrates age related changes in the lens of the human eye. (CW)

  16. Eye Protection in Kansas Schools.

    ERIC Educational Resources Information Center

    Hay, Kenneth M.; And Others

    A law passed by a state legislature requires that students in industrial arts shops and science laboratories must wear eye protective devices. Explanatory material presents the text of the bill and guidelines for implementation, including--(1) types of eye hazards, (2) types of protective devices, (3) administrating eye safety equipment, (4)…

  17. Reconstructing the eyes of Urbilateria.

    PubMed Central

    Arendt, D; Wittbrodt, J

    2001-01-01

    The shared roles of Pax6 and Six homologues in the eye development of various bilaterians suggest that Urbilateria, the common ancestors of all Bilateria, already possessed some simple form of eyes. Here, we re-address the homology of bilaterian cerebral eyes at the level of eye anatomy, of eye-constituting cell types and of phototransductory molecules. The most widespread eye type found in Bilateria are the larval pigment-cup eyes located to the left and right of the apical organ in primary, ciliary larvae of Protostomia and Deuterostomia. They can be as simple as comprising a single pigment cell and a single photoreceptor cell in inverse orientation. Another more elaborate type of cerebral pigment-cup eyes with an everse arrangement of photoreceptor cells is found in adult Protostomia. Both inverse larval and everse adult eyes employ rhabdomeric photoreceptor cells and thus differ from the chordate cerebral eyes with ciliary photoreceptors. This is highly significant because on the molecular level we find that for phototransduction rhabdomeric versus ciliary photoreceptor cells employ divergent rhodopsins and non-orthologous G-proteins, rhodopsin kinases and arrestins. Our comparison supports homology of cerebral eyes in Protostomia; it challenges, however, homology of chordate and non-chordate cerebral eyes that employ photoreceptor cells with non-orthologous phototransductory cascades. PMID:11604122

  18. LIMNOLOGICAL OPTOMETRY: EXAMINING EARTH'S EYE

    EPA Science Inventory

    In Thoreau's Walden, a lake is described as the landscape's most expressive feature and the earth's eye. Collectively, scientists are charged by society to assess, monitor, and remedy maladies of earth's eye in the same way optometrists maintain the health of the human eye. This ...

  19. Hand Controller Assembly

    NASA Technical Reports Server (NTRS)

    Bandera, Pablo (Inventor); Buchele, Paul (Inventor)

    2015-01-01

    A user input device for a vehicular electrical system is provided. The user input device includes a handle sized and shaped to be gripped by a human hand and a gimbal assembly within the handle. The gimbal assembly includes a first gimbal component, a second gimbal component coupled to the first gimbal component such that the second gimbal component is rotatable relative to the first gimbal component about a first axis, and a third gimbal component coupled to the second gimbal component such that the third gimbal component is rotatable relative to the second gimbal component about a second axis.

  20. What Happens After Treatment for Eye Cancer?

    MedlinePlus

    ... having eye cancer What happens after treatment for eye cancer? For many people with eye cancer, treatment ... manage them. Follow-up after treatment of uveal (eye) melanoma Your doctor will most likely want to ...

  1. What Is a Comprehensive Dilated Eye Exam?

    MedlinePlus

    ... su oculista What is a comprehensive dilated eye exam? You may think your eyes are healthy, but ... eye care professional for a comprehensive dilated eye exam is the only way to really be sure. ...

  2. Behavioral Impact of Unisensory and Multisensory Audio-Tactile Events: Pros and Cons for Interlimb Coordination in Juggling

    PubMed Central

    Zelic, Gregory; Mottet, Denis; Lagarde, Julien

    2012-01-01

    Recent behavioral neuroscience research revealed that elementary reactive behavior can be improved in the case of cross-modal sensory interactions thanks to underlying multisensory integration mechanisms. Can this benefit be generalized to an ongoing coordination of movements under severe physical constraints? We choose a juggling task to examine this question. A central issue well-known in juggling lies in establishing and maintaining a specific temporal coordination among balls, hands, eyes and posture. Here, we tested whether providing additional timing information about the balls and hands motions by using external sound and tactile periodic stimulations, the later presented at the wrists, improved the behavior of jugglers. One specific combination of auditory and tactile metronome led to a decrease of the spatiotemporal variability of the juggler's performance: a simple sound associated to left and right tactile cues presented antiphase to each other, which corresponded to the temporal pattern of hands movement in the juggling task. A contrario, no improvements were obtained in the case of other auditory and tactile combinations. We even found a degraded performance when tactile events were presented alone. The nervous system thus appears able to integrate in efficient way environmental information brought by different sensory modalities, but only if the information specified matches specific features of the coordination pattern. We discuss the possible implications of these results for the understanding of the neuronal integration process implied in audio-tactile interaction in the context of complex voluntary movement, and considering the well-known gating effect of movement on vibrotactile perception. PMID:22384211

  3. Back to basics: hand hygiene and surgical hand antisepsis.

    PubMed

    Spruce, Lisa

    2013-11-01

    Health care-associated infections (HAIs) are a significant issue in the United States and throughout the world, but following proper hand hygiene practices is the most effective and least expensive way to prevent HAIs. Hand hygiene is inexpensive and protects patients and health care personnel alike. The four general types of hand hygiene that should be performed in the perioperative environment are washing hands that are visibly soiled, hand hygiene using alcohol-based products, surgical hand scrubs, and surgical hand scrubs using an alcohol-based surgical hand rub product. Barriers to proper hand hygiene may include not thinking about it, forgetting, skin irritation, a lack of role models, or a lack of a safety culture. One strategy for improving hand hygiene practices is monitoring hand hygiene as part of a quality improvement project, but the most important aspect for perioperative team members is to set an example for other team members by following proper hand hygiene practices and reminding each other to perform hand hygiene. PMID:24209795

  4. TrackEye tracking algorithm characterization

    NASA Astrophysics Data System (ADS)

    Valley, Michael T.; Shields, Robert W.; Reed, Jack M.

    2004-10-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  5. TrackEye tracking algorithm characterization.

    SciTech Connect

    Reed, Jack W.; Shields, Rob W; Valley, Michael T.

    2004-08-01

    TrackEye is a film digitization and target tracking system that offers the potential for quantitatively measuring the dynamic state variables (e.g., absolute and relative position, orientation, linear and angular velocity/acceleration, spin rate, trajectory, angle of attack, etc.) for moving objects using captured single or dual view image sequences. At the heart of the system is a set of tracking algorithms that automatically find and quantify the location of user selected image details such as natural test article features or passive fiducials that have been applied to cooperative test articles. This image position data is converted into real world coordinates and rates with user specified information such as the image scale and frame rate. Though tracking methods such as correlation algorithms are typically robust by nature, the accuracy and suitability of each TrackEye tracking algorithm is in general unknown even under good imaging conditions. The challenges of optimal algorithm selection and algorithm performance/measurement uncertainty are even more significant for long range tracking of high-speed targets where temporally varying atmospheric effects degrade the imagery. This paper will present the preliminary results from a controlled test sequence used to characterize the performance of the TrackEye tracking algorithm suite.

  6. Active inference, eye movements and oculomotor delays.

    PubMed

    Perrinet, Laurent U; Adams, Rick A; Friston, Karl J

    2014-12-01

    This paper considers the problem of sensorimotor delays in the optimal control of (smooth) eye movements under uncertainty. Specifically, we consider delays in the visuo-oculomotor loop and their implications for active inference. Active inference uses a generalisation of Kalman filtering to provide Bayes optimal estimates of hidden states and action in generalised coordinates of motion. Representing hidden states in generalised coordinates provides a simple way of compensating for both sensory and oculomotor delays. The efficacy of this scheme is illustrated using neuronal simulations of pursuit initiation responses, with and without compensation. We then consider an extension of the generative model to simulate smooth pursuit eye movements-in which the visuo-oculomotor system believes both the target and its centre of gaze are attracted to a (hidden) point moving in the visual field. Finally, the generative model is equipped with a hierarchical structure, so that it can recognise and remember unseen (occluded) trajectories and emit anticipatory responses. These simulations speak to a straightforward and neurobiologically plausible solution to the generic problem of integrating information from different sources with different temporal delays and the particular difficulties encountered when a system-like the oculomotor system-tries to control its environment with delayed signals. PMID:25128318

  7. Grid-coordinate generation program

    USGS Publications Warehouse

    Cosner, Oliver J.; Horwich, Esther

    1974-01-01

    This program description of the grid-coordinate generation program is written for computer users who are familiar with digital aquifer models. The program computes the coordinates for a variable grid -used in the 'Pinder Model' (a finite-difference aquifer simulator), for input to the CalComp GPCP (general purpose contouring program). The program adjusts the y-value by a user-supplied constant in order to transpose the origin of the model grid from the upper left-hand corner to the lower left-hand corner of the grid. The user has the options of, (1.) choosing the boundaries of the plot; (2.) adjusting the z-values (altitudes) by a constant; (3.) deleting superfluous z-values and (4.) subtracting the simulated surfaces from each other to obtain the decline. Output of this program includes the fixed format CNTL data cards and the other data cards required for input to GPCP. The output from GPCP then is used to produce a potentiometric map or a decline map by means of the CalComp plotter.

  8. Modulation of hand aperture during reaching in persons with incomplete cervical spinal cord injury

    PubMed Central

    Stahl, Victoria; Hayes, Heather B; Buetefisch, Cathrin; Wolf, Steven L; Trumbower, Randy D

    2014-01-01

    The intact neuromotor system prepares for object grasp by first opening the hand to an aperture that is scaled according to object size and then closing the hand around the object. After cervical spinal cord injury (SCI), hand function is significantly impaired, but the degree to which object-specific hand aperture scaling is affected remains unknown. Here we hypothesized that persons with incomplete cervical SCI have a reduced maximum hand opening capacity but exhibit novel neuromuscular coordination strategies that permit object-specific hand aperture scaling during reaching. To test this hypothesis, we measured hand kinematics and surface electromyography (EMG) from seven muscles of the hand and wrist during attempts at maximum hand opening as well as reaching for four balls of different diameters. Our results showed that persons with SCI exhibited significantly reduced maximum hand aperture compared to able-bodied (AB) controls. However, persons with SCI preserved the ability to scale peak hand aperture with ball size during reaching. Persons with SCI also used distinct muscle coordination patterns that included increased co-activity of flexors and extensors at the wrist and hand compared to AB controls. These results suggest that motor planning for aperture modulation is preserved even though execution is limited by constraints on hand opening capacity and altered muscle co-activity. Thus, persons with incomplete cervical SCI may benefit from rehabilitation aimed at increasing hand opening capacity and reducing flexor-extensor co-activity at the wrist and hand. PMID:25511164

  9. Modulation of hand aperture during reaching in persons with incomplete cervical spinal cord injury.

    PubMed

    Stahl, Victoria A; Hayes, Heather B; Buetefisch, Cathrin M; Wolf, Steven L; Trumbower, Randy D

    2015-03-01

    The intact neuromotor system prepares for object grasp by first opening the hand to an aperture that is scaled according to object size and then closing the hand around the object. After cervical spinal cord injury (SCI), hand function is significantly impaired, but the degree to which object-specific hand aperture scaling is affected remains unknown. Here, we hypothesized that persons with incomplete cervical SCI have a reduced maximum hand opening capacity but exhibit novel neuromuscular coordination strategies that permit object-specific hand aperture scaling during reaching. To test this hypothesis, we measured hand kinematics and surface electromyography from seven muscles of the hand and wrist during attempts at maximum hand opening as well as reaching for four balls of different diameters. Our results showed that persons with SCI exhibited significantly reduced maximum hand aperture compared to able-bodied (AB) controls. However, persons with SCI preserved the ability to scale peak hand aperture with ball size during reaching. Persons with SCI also used distinct muscle coordination patterns that included increased co-activity of flexors and extensors at the wrist and hand compared to AB controls. These results suggest that motor planning for aperture modulation is preserved even though execution is limited by constraints on hand opening capacity and altered muscle co-activity. Thus, persons with incomplete cervical SCI may benefit from rehabilitation aimed at increasing hand opening capacity and reducing flexor-extensor co-activity at the wrist and hand. PMID:25511164

  10. Artificial dexterous hand

    NASA Technical Reports Server (NTRS)

    Lee, Sukhan (Inventor)

    1990-01-01

    An artificial dexterous hand is provided for conformally engaging and manipulating objects. The hand includes an articulated digit which is connected to an engagement sub-assembly and has a first shape adaption mechanism associated with it. The digit has a digit base and first and second phalanges. The digit base is operatively interconnected to the first phalange by a base joint having a base pulley. The phalanges are operatively interconnected by a separate first phalange joint having a first phalange pulley. The engagement sub-assembly includes a tendon, which is received by the base pulley and by the first phalange pulley, and an actuation device for selectively tensioning the tendon. The first shape adaption mechanism is responsive to and receives the tendon. It is also situated between the base joint and the first phalange joint and is connected to the first phalange. Upon actuation by the actuation device, the phalanges are caused to pivot relative to the base joint and the second phalange is caused to pivot relative to the first phalange. At the same time, the first shape adaption mechanism controls the sequence of the aforementioned pivoting of the phalanges through application of braking force to the tendon.

  11. [Conservative treatment of dry eye].

    PubMed

    Hefner, J; Reinshagen, H

    2014-11-01

    The use of topic anti-inflammatory drugs has become very important in the treatment of dry eye disease. Besides the basic therapy including tear replacement, use of serum eye drops and mucolytic eye drops, the topical application of corticosteroids and cyclosporin A is more commonly used in moderate to severe forms of dry eye disease. The consistent treatment of Meibomian gland dysfunction as a frequent reason for evaporative dry eye is also of particular importance. Understanding the chronicity of the disease and long-term compliance are the essential for successful therapy of this widespread disease. PMID:25275793

  12. Effects of Handedness and Saccadic Bilateral Eye Movements on Components of Autobiographical Recollection

    ERIC Educational Resources Information Center

    Parker, Andrew; Dagnall, Neil

    2010-01-01

    The effects of handedness and saccadic bilateral eye movements on autobiographical recollection were investigated. Recall of autobiographical memories was cued by the use of neutral and emotional words. Autobiographical recollection was assessed by the autobiographical memory questionnaire. Experiment 1 found that mixed-handed (vs. right handed)…

  13. Eye movement abnormalities.

    PubMed

    Moncayo, Jorge; Bogousslavsky, Julien

    2012-01-01

    Generation and control of eye movements requires the participation of the cortex, basal ganglia, cerebellum and brainstem. The signals of this complex neural network finally converge on the ocular motoneurons of the brainstem. Infarct or hemorrhage at any level of the oculomotor system (though more frequent in the brain-stem) may give rise to a broad spectrum of eye movement abnormalities (EMAs). Consequently, neurologists and particularly stroke neurologists are routinely confronted with EMAs, some of which may be overlooked in the acute stroke setting and others that, when recognized, may have a high localizing value. The most complex EMAs are due to midbrain stroke. Horizontal gaze disorders, some of them manifesting unusual patterns, may occur in pontine stroke. Distinct varieties of nystagmus occur in cerebellar and medullary stroke. This review summarizes the most representative EMAs from the supratentorial level to the brainstem. PMID:22377853

  14. Nutrition and the eye.

    PubMed

    Congdon, N G; West, K P

    1999-12-01

    The topic "nutrition and the eye" cannot adequately be covered in a single review article; indeed, dozens of books and hundreds of articles have been written on the subject. This review concentrates on three areas in which specific nutrients are known or theorized to have a major impact on vision and the visual system: vitamin A deficiency; antioxidants and their proposed role in the prevention of age-related cataract and macular degeneration; and nutritional optic neuropathies, including those of the recent Cuban epidemic. In addition, this article touches on nutritional treatments that have been suggested for several less common eye diseases and, finally, considers several less prevalent conditions in which deficiency of or excess exposure to a particular nutrient has been associated with ocular pathology. PMID:10662253

  15. [The eye and cancer].

    PubMed

    Schalenbourg, Ann; Mantel, Irmela

    2015-12-16

    Cancer involves so rarely the eye that it may be recognized late. The most frequent primary intra-ocular tumours are retinoblastoma in small children and uveal melanoma in adults. Vision loss in systemic cancer has a varied differential diagnosis. Uveal metastases are most often associated with breast cancer, but can herald lung carcinoma. Masquerade syndrome looks like inflammation but represents the ocular involvement of primary CNS non-Hodgkin lymphoma. Systemic cancer drugs, as well as radiotherapy, can cause ocular toxicity, mostly at the retina. In the rare paraneoplastic syndromes, patient's cancer antibodies cross-react with retinal antigens, leading to severe vision loss. When cancer involves the eye, a fast referral into specialized care can significantly improve visual and vital prognosis. PMID:26852556

  16. Movement and Coordination

    MedlinePlus

    ... will seem to be continually on the go—running, kicking, climbing, jumping. His attention span, which was ... his coordination. In the months ahead, your child’s running will become smoother and more coordinated. He’ll ...

  17. Pioneers of eye movement research

    PubMed Central

    Wade, Nicholas J

    2010-01-01

    Recent advances in the technology affording eye movement recordings carry the risk of neglecting past achievements. Without the assistance of this modern armoury, great strides were made in describing the ways the eyes move. For Aristotle the fundamental features of eye movements were binocular, and he described the combined functions of the eyes. This was later given support using simple procedures like placing a finger over the eyelid of the closed eye and culminated in Hering's law of equal innervation. However, the overriding concern in the 19th century was with eye position rather than eye movements. Appreciating discontinuities of eye movements arose from studies of vertigo. The characteristics of nystagmus were recorded before those of saccades and fixations. Eye movements during reading were described by Hering and by Lamare in 1879; both used similar techniques of listening to sounds made during contractions of the extraocular muscles. Photographic records of eye movements during reading were made by Dodge early in the 20th century, and this stimulated research using a wider array of patterns. In the mid-20th century attention shifted to the stability of the eyes during fixation, with the emphasis on involuntary movements. The contributions of pioneers from Aristotle to Yarbus are outlined. PMID:23396982

  18. Michelangelo's eye disease.

    PubMed

    Gallenga, P E; Neri, Giampiero; D'Anastasio, Ruggero; Pettorrossi, Vito Enrico; Alfieri, Emilio; Capasso, Luigi

    2012-06-01

    Charged by the Pope Julius II for painting the Cappella Sistina in Rome (between 1508 and 1512), Michelangelo worked in an elevated scaffolding, in an anomalous position with dyes (including poisoning lead salts) and solvents (such as toxic turpentine) dripping on his face and continuously inhaling, in a dim environment illuminated only with oil lamps and candles, as he described himself and sketched in a sonet addressed to Giovanni da Pistoia. In 1510 he began suffering from eye disease: the main symptom was the necessity to elevate the document he was reading up to the level of his eyes. This defect disappeared few months after he finished painting his masterpiece. We hypothesize that the Michelangelo's eyes disease was a form of acquired and transitory nystagmus induced by the many hours he spent in up gaze, with a skew deviation, a form of ocular tilt reaction resulting from the impairment of spatial sensitivity (inversion illusion) due to the persistence of the artist's head in a horizontal position, looking upward. PMID:22425178

  19. Schizophrenia and the eye

    PubMed Central

    Silverstein, Steven M.; Rosen, Richard

    2015-01-01

    Although visual processing impairments are common in schizophrenia, it is not clear to what extent these originate in the eye vs. the brain. This review highlights potential contributions, from the retina and other structures of the eye, tovisual processing impairments in schizophrenia and high-risk states. A second goal is to evaluate the status of retinal abnormalities as biomarkers for schizophrenia. The review was motivated by known retinal changes in other disorders (e.g., Parkinson's disease, multiple sclerosis), and their relationships to perceptual and cognitive impairments, and disease progression therein. The evidence reviewed suggests two major conclusions. One is that there are multiple structural and functional disturbances of the eye in schizophrenia, all of which could be factors in the visual disturbances of patients. These include retinal venule widening, retinal nerve fiber layer thinning, dopaminergic abnormalities, abnormal ouput of retinal cells as measured by electroretinography (ERG), maculopathies and retinopathies, cataracts, poor acuity, and strabismus. Some of these are likely to be illness-related, whereas others may be due to medication or comorbid conditions. The second conclusion is that certain retinal findings can serve as biomarkers of neural pathology, and disease progression, in schizophrenia. The strongest evidence for this to date involves findings of widened retinal venules, thinning of the retinal nerve fiber layer, and abnormal ERG amplitudes. These data suggest that a greater understanding of the contribution of retinal and other ocular pathology to the visual and cognitive disturbances of schizophrenia is warranted, and that retinal changes have untapped clinical utility. PMID:26345525

  20. Christoph Scheiner's eye studies.

    PubMed

    Daxecker, F

    1992-01-01

    Christoph Scheiner was born in 1573 or 1575. In 1595 he entered into the Order of the Jesuits; he died in 1650. In 1619 his book Oculus, dealing with the optics of the eye, appeared in Innsbruck. The invention of the telescope was of utmost importance for progress in astronomical and physical research. Scheiner himself built telescopes and discovered the sunspots. As a result, an unpleasant priority dispute with Galilei ensued. From 1624 onwards, Scheiner was in Rome, where his main work Rosa Ursina was published in 1630. A part of this book deals with the physiological optics of the eye as well. Some of his discoveries and experiments are taken from these two books: determination of the radius of curvature of the cornea, discovery of the nasal exit of the optic nerve, increase in the radius of curvature of the lens in case of accommodation, Scheiner's procedure (double images with ametropia), refractive indices of various parts of the eye, Scheiner's experiment. Without any doubt, Christoph Scheiner belongs to the foremost scientists of the first half of the 17th century. PMID:1473465

  1. A Zn based coordination polymer exhibiting long-lasting phosphorescence.

    PubMed

    Cepeda, Javier; Sebastian, Eider San; Padro, Daniel; Rodríguez-Diéguez, Antonio; García, Jose A; Ugalde, Jesus M; Seco, Jose M

    2016-07-01

    A new Zn(ii) based coordination polymer (CP) built by the cohesive pilling of 2D Shubnikov type layers is reported. This material exhibits time dependent multicoloured emission, part of which shows a persistent green phosphorescence visible for up to two seconds to the naked eye, which originates from multiple charge transfer mechanisms. PMID:27297330

  2. New Angles on Motor and Sensory Coordination in Learning Disabilities.

    ERIC Educational Resources Information Center

    Goldey, Ellen S.

    1998-01-01

    Provides an overview of presentations that were included in the Medical Symposium at the 1998 Learning Disabilities Association conference. The symposium addressed vestibular control and eye movement, postural sway and balance, cerebellar dysfunction, the role of the frontal lobe, developmental coordination disorder, and sensory integration…

  3. Hands Up: Attentional Prioritization of Space Near the Hand

    ERIC Educational Resources Information Center

    Reed, Catherine L.; Grubb, Jefferson D.; Steele, Cleophus

    2006-01-01

    This study explored whether hand location affected spatial attention. The authors used a visual covert-orienting paradigm to examine whether spatial attention mechanisms--location prioritization and shifting attention--were supported by bimodal, hand-centered representations of space. Placing 1 hand next to a target location, participants detected…

  4. Processing Coordination Ambiguity

    ERIC Educational Resources Information Center

    Engelhardt, Paul E.; Ferreira, Fernanda

    2010-01-01

    We examined temporarily ambiguous coordination structures such as "put the butter in the bowl and the pan on the towel." Minimal Attachment predicts that the ambiguous noun phrase "the pan" will be interpreted as a noun-phrase coordination structure because it is syntactically simpler than clausal coordination. Constraint-based theories assume…

  5. Analysis Coordinator Report

    NASA Technical Reports Server (NTRS)

    Nothnagel, A.

    2013-01-01

    We present the IVS analysis coordination issues of 2012. The IVS Analysis Coordinator is responsible for generating and disseminating the official IVS products. This requires consistency of the input data by strict adherence to models and conventions. The term of the current IVS Analysis Coordinator will end on February 28, 2013.

  6. Predicting the Valence of a Scene from Observers’ Eye Movements

    PubMed Central

    R.-Tavakoli, Hamed; Atyabi, Adham; Rantanen, Antti; Laukka, Seppo J.; Nefti-Meziani, Samia; Heikkilä, Janne

    2015-01-01

    Multimedia analysis benefits from understanding the emotional content of a scene in a variety of tasks such as video genre classification and content-based image retrieval. Recently, there has been an increasing interest in applying human bio-signals, particularly eye movements, to recognize the emotional gist of a scene such as its valence. In order to determine the emotional category of images using eye movements, the existing methods often learn a classifier using several features that are extracted from eye movements. Although it has been shown that eye movement is potentially useful for recognition of scene valence, the contribution of each feature is not well-studied. To address the issue, we study the contribution of features extracted from eye movements in the classification of images into pleasant, neutral, and unpleasant categories. We assess ten features and their fusion. The features are histogram of saccade orientation, histogram of saccade slope, histogram of saccade length, histogram of saccade duration, histogram of saccade velocity, histogram of fixation duration, fixation histogram, top-ten salient coordinates, and saliency map. We utilize machine learning approach to analyze the performance of features by learning a support vector machine and exploiting various feature fusion schemes. The experiments reveal that ‘saliency map’, ‘fixation histogram’, ‘histogram of fixation duration’, and ‘histogram of saccade slope’ are the most contributing features. The selected features signify the influence of fixation information and angular behavior of eye movements in the recognition of the valence of images. PMID:26407322

  7. Predicting the Valence of a Scene from Observers' Eye Movements.

    PubMed

    R-Tavakoli, Hamed; Atyabi, Adham; Rantanen, Antti; Laukka, Seppo J; Nefti-Meziani, Samia; Heikkilä, Janne

    2015-01-01

    Multimedia analysis benefits from understanding the emotional content of a scene in a variety of tasks such as video genre classification and content-based image retrieval. Recently, there has been an increasing interest in applying human bio-signals, particularly eye movements, to recognize the emotional gist of a scene such as its valence. In order to determine the emotional category of images using eye movements, the existing methods often learn a classifier using several features that are extracted from eye movements. Although it has been shown that eye movement is potentially useful for recognition of scene valence, the contribution of each feature is not well-studied. To address the issue, we study the contribution of features extracted from eye movements in the classification of images into pleasant, neutral, and unpleasant categories. We assess ten features and their fusion. The features are histogram of saccade orientation, histogram of saccade slope, histogram of saccade length, histogram of saccade duration, histogram of saccade velocity, histogram of fixation duration, fixation histogram, top-ten salient coordinates, and saliency map. We utilize machine learning approach to analyze the performance of features by learning a support vector machine and exploiting various feature fusion schemes. The experiments reveal that 'saliency map', 'fixation histogram', 'histogram of fixation duration', and 'histogram of saccade slope' are the most contributing features. The selected features signify the influence of fixation information and angular behavior of eye movements in the recognition of the valence of images. PMID:26407322

  8. Compact artificial hand

    NASA Technical Reports Server (NTRS)

    Wiker, G. A.; Mann, W. A. (Inventor)

    1979-01-01

    A relatively simple, compact artificial hand, is described which includes hooks pivotally mounted on first frame to move together and apart. The first frame is rotatably mounted on a second frame to enable "turning at the wrist" movement without limitation. The second frame is pivotally mounted on a third frame to permit 'flexing at the wrist' movement. A hook-driving motor is fixed to the second frame but has a shaft that drives a speed reducer on the first frame which, in turn, drives the hooks. A second motor mounted on the second frame, turns a gear on the first frame to rotate the first frame and the hooks thereon. A third motor mounted on the third frame, turns a gear on a second frame to pivot it.

  9. Metalworking fluid hand dermatitis.

    PubMed

    Ueno, Saori; Shiomi, Yuko; Yokota, Kozo

    2002-07-01

    In a household appliance plant, several rinse-free lubricating fluids have been used instead of neat mineral oils since 1994: mixtures of isoparaffinic hydrocarbons with 9 to 14 carbons per molecule. As such they denature keratin, irritate and defat the skin, and remove water from it. Work gloves have been worn over plastic gloves and separate, reusable, cotton inner gloves have been added to absorb sweat since skin problems were first recognized in 1994. All 74 males (mean +/- SD, 38.8 +/- 8.0 years) who work with the fluids were interviewed and given cutaneous examinations when indicated. While 4 cases of severe dermatitis and 31 cases of mild dermatitis were identified, 28 individuals gave a history of similar problems since the use of lubricating fluids. Their symptoms were typical of primary skin irritation. The hands were the commonly affected region (63 of 63 cases: 100%), followed by the thighs (15.9%) and trunk (11.1%). The work-related skin symptoms identified were less common in workers who immediately removed the liquid with soap and water, when it is spilled on the hands, than in those who did not, but the difference was not statistically significant (7/23 (30.4%) vs. 28/51 (54.9%), p=0.051 by chi-square test). Since skin contact with metalworking fluids (MWF) is often unavoidable, good personal hygiene is important in minimizing potential adverse health effects. Health education thus remains the most important preventive measure against irritant contact dermatitis among workers handling MWFs. PMID:12141380

  10. Hand-foot-mouth disease

    MedlinePlus

    Hand-foot-mouth disease is a common viral infection that most often begins in the throat. ... Hand-foot-mouth disease (HFMD) is most commonly caused by a virus called coxsackievirus A16. Children under age 10 are most ...

  11. Hand-foot-mouth disease

    MedlinePlus

    ... medlineplus.gov/ency/article/000965.htm Hand-foot-mouth disease To use the sharing features on this page, please enable JavaScript. Hand-foot-mouth disease is a common viral infection that most ...

  12. Altered Vision Near the Hands

    ERIC Educational Resources Information Center

    Abrams, Richard A.; Davoli, Christopher C.; Du, Feng; Knapp, William H., III; Paull, Daniel

    2008-01-01

    The present study explored the manner in which hand position may affect visual processing. We studied three classic visual attention tasks (visual search, inhibition of return, and attentional blink) during which the participants held their hands either near the stimulus display, or far from the display. Remarkably, the hands altered visual…

  13. Hand Hygiene: When and How

    MedlinePlus

    ... SOILED Duration of the entire procedure: 20-30 seconds WASH HANDS WHEN VISIBLY SOILED! OTHERWISE, USE HANDRUB Duration of the entire procedure: 40-60 seconds 1 a 1 b 2 012 Apply a palmful of the product in a cupped hand, covering all surfaces; Rub hands palm to palm; ...

  14. Movement Coordination during Conversation

    PubMed Central

    Latif, Nida; Barbosa, Adriano V.; Vatiokiotis-Bateson, Eric; Castelhano, Monica S.; Munhall, K. G.

    2014-01-01

    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. PMID:25119189

  15. Covert preparation of a manual response in a ‘go’/‘no-go’ saccadic task is driven by execution of the eye movement and not by visual stimulus occurrence

    PubMed Central

    Maioli, Claudio; Falciati, Luca

    2015-01-01

    It has been recently demonstrated that visually guided saccades are linked to changes in muscle excitability in the relaxed upper limb, which are compatible with a covert motor plan encoding a hand movement toward the gaze target. In this study we investigated whether these excitability changes are time locked to the visual stimulus, as predicted by influential attention models, or are strictly dependent on saccade execution. Single-pulse transcranial magnetic stimulation was applied to the motor cortex at eight different time delays during a ‘go’/‘no-go’ task, which involved overt or covert orienting of attention. By analyzing the time course of excitability in three hand muscles, synchronized with the onset of either the attentional cue or the eye movement, we demonstrated that side- and muscle-specific excitability changes were strictly time locked to the saccadic response and were not correlated to the onset of the visual attentive stimulus. Furthermore, muscle excitability changes were absent following a covert shift of attention. We conclude that a sub-threshold manual motor plan is automatically activated by the saccade decision-making process, as part of a covert eye-hand coordination program. We found no evidence for a representation of spatial attention within the upper limb motor map. PMID:26483664

  16. Hand placement techniques in long horse vaulting.

    PubMed

    Kerwin, D G; Harwood, M J; Yeadon, M R

    1993-08-01

    In this study, the effects of two different hand placement techniques used by gymnasts to perform Tsukahara and Kasamatsu long horse vaults were examined. Selected linear and angular flight descriptors were calculated to determine whether those gymnasts making initial hand contact on the end of the horse gained additional lift, range or rotation when compared to those gymnasts making the more traditional initial hand contact on top of the horse. Three-dimensional cine-film analysis using the Direct Linear Transformation (DLT) was used to obtain data on 17 elite gymnasts competing in the 1991 World Student Games at Sheffield, UK. The gymnasts were divided into two groups according to the techniques used: group E in which the first hand contact was made on the vertical surface of the near end and the second on the top of the horse, and group T in which both hands were placed on top of the horse. The vertical and horizontal motion of each gymnast's mass centre and the somersault rotation during pre-flight (board take-off to horse contact) and post-flight (horse take-off to ground landing) were determined. The projections of linear displacements of each gymnast's mass centre onto a vertical plane were determined from the three-dimensional mass centre co-ordinates, and somersault angles were calculated using the line joining the midpoints of each gymnast's shoulders and knees. Whole body mass centre linear velocity and somersault angular velocity were determined using quintic splines.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8230392

  17. Adventures in Coordinate Space

    NASA Astrophysics Data System (ADS)

    Chambers, J. E.

    2003-08-01

    A variety of coordinate systems have been used to study the N-body problem for cases involving a dominant central mass. These include the traditional Keplerian orbital elements and the canonical Delaunay variables, which both incorporate conserved quantities of the two-body problem. Recently, Cartesian coordinate systems have returned to favour with the rise of mixed-variable symplectic integrators, since these coordinates prove to be more efficient than using orbital elements. Three sets of canonical Cartesian coordinates are well known, each with its own advantages and disadvantages. Inertial coordinates (which include barycentric coordinates as a special case) are the simplest and easiest to implement. However, they suffer from the disadvantage that the motion of the central body must be calculated explicitly, leading to relatively large errors in general. Jacobi coordinates overcome this problem by replacing the coordinates and momenta of the central body with those of the system as a whole, so that momentum is conserved exactly. This leads to substantial improvements in accuracy, but has the disadvantage that every object is treated differently, and interactions between each pair of bodies are now expressed in a complicated manner involving the coordinates of many bodies. Canonical heliocentric coordinates (also known as democratic heliocentric coordinates) treat all bodies equally, and conserve the centre of mass motion, but at the cost of introducing momentum cross terms into the kinetic energy. This complicates the development of higher order symplectic integrators and symplectic correctors, as well as the development of methods used to resolve close encounters with the central body. Here I will re-examine the set of possible canonical Cartesian coordinate systems to determine if it is possible to (a) conserve the centre of mass motion, (b) treat all bodies equally, and (c) eliminate the momentum cross terms. I will demonstrate that this is indeed possible

  18. How to administer eye drops and eye ointment.

    PubMed

    Shaw, Mary

    2016-05-25

    Rationale and key points Eye drops and eye ointment are the mainstay of treatment of ocular conditions. Failure to prioritise administration of these medicines can prolong the condition and may present a risk to the patient's vision. ▶ Eye drops and eye ointments are used to treat acute and chronic conditions of the eye and surrounding structures. Eye drops must be instilled before applying eye ointment, since the ointment will affect the absorption of the eye drop. ▶ Nurses require knowledge of the technique, side effects and potential interactions associated with systemically or topically applied medicines to the eye to ensure patient safety and optimum outcomes. Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. How this article will change your practice. 2. How you intend to develop your knowledge and skills regarding treatment of ocular conditions. Subscribers can update their reflective accounts at rcni.com/portfolio. PMID:27224628

  19. The use of predictive information is impaired in the actions of children and young adults with Developmental Coordination Disorder.

    PubMed

    Wilmut, Kate; Wann, John

    2008-12-01

    The need for a movement response may often be preceded by some advance information regarding direction or extent. We examined the ability of individuals with Developmental Coordination Disorder (DCD) to organise a movement in response to advance information. Pre-cues were presented and varied in the extent to which they indicated the response target. Both eye movement latencies and hand movements were measured. In the absence of pre-cues, individuals with DCD were as fast in initial hand movements as the typically developing (TD) participants, but were less efficient at correcting initial directional errors. A major difference was seen in the degree to which each group could use advance pre-cue information. TD participants were able to use pre-cue information to refine their actions. For the individuals with DCD this was only effective if there was no ambiguity in the advance cue and they had particular difficulty in using predictive motion cues. There were no differences in the speed of gaze responses which excluded an explanation relating to the dynamic allocation of attention. Individuals with DCD continued to rely on the slower strategy of fixating the target prior to initiating a hand movement, rather than using advance information to set initial movement parameters. PMID:18709366

  20. Computer control by hand gestures

    NASA Astrophysics Data System (ADS)

    Jemel, Intidhar; Ejbali, Ridha; Zaied, Mourad

    2015-12-01

    This work fits into the context of the interpretation of automatic gestures based on computer vision. The aim of our work is to transform a conventional screen in a surface that allows the user to use his hands as pointing devices. These can be summarized in three main steps. Hand detection in a video, monitoring detected hands and conversion paths made by the hands to computer commands. To realize this application, it is necessary to detect the hand to follow. A classification phase is essential, at the control part. For this reason, we resorted to the use of a neuro-fuzzy classifier for classification and a pattern matching method for detection.

  1. [Eye and the environment].

    PubMed

    Voide, Nathalie; Kaeser, Pierre-François; Behar-Cohen, Francine

    2015-12-16

    The eyes are exposed to multiple environmental factors, which affect visual development, comfort, and visual health. While overexposure to sunlight can cause ocular surface and retinal pathologies, insufficient exposure to daylight could significantly contribute to myopia progression. New artificial lights, namely LED, have a higher risk of retinal phototoxicity, and could alter ocular circadian rhythm. The significant increase of prevalence of ocular allergies could be caused by the proliferation of environmental polluting substances, like tobacco smoke, fuel combustion by-products, or phtalates, which are found in many types of plastics. Finally, some dietary supplements could play a protective role in certain types of ocular pathologies, namely retinal pathologies. PMID:26852551

  2. Lens of Eye Dosimetry

    SciTech Connect

    Mallett, Michael Wesley

    2015-03-23

    An analysis of LANL occupational dose measurements was made with respect to lens of eye dose (LOE), in particular, for plutonium workers. Table 1 shows the reported LOE as a ratio of the “deep” (photon only) and “deep+neutron” dose for routine monitored workers at LANL for the past ten years. The data compares the mean and range of these values for plutonium workers* and non-routine plutonium workers. All doses were reported based on measurements with the LANL Model 8823 TLD.

  3. Prosthetic helping hand

    NASA Technical Reports Server (NTRS)

    Vest, Thomas W. (Inventor); Carden, James R. (Inventor); Norton, William E. (Inventor); Belcher, Jewell G. (Inventor)

    1992-01-01

    A prosthetic device for below-the-elbow amputees, having a C-shaped clamping mechanism for grasping cylindrical objects, is described. The clamping mechanism is pivotally mounted to a cuff that fits on the amputee's lower arm. The present invention is utilized by placing an arm that has been amputated below the elbow into the cuff. The clamping mechanism then serves as a hand whenever it becomes necessary for the amputee to grasp a cylindrical object such as a handle, a bar, a rod, etc. To grasp the cylindrical object, the object is jammed against the opening in the C-shaped spring, causing the spring to open, the object to pass to the center of the spring, and the spring to snap shut behind the object. Various sizes of clamping mechanisms can be provided and easily interchanged to accommodate a variety of diameters. With the extension that pivots and rotates, the clamping mechanism can be used in a variety of orientations. Thus, this invention provides the amputee with a clamping mechanism that can be used to perform a number of tasks.

  4. Pathology of a lepromatous eye.

    PubMed

    Ebenezer, G J; Daniel, E

    2000-03-01

    Histopathological examination of an enucleated eye from a lepromatous leprosy patient showed the cornea, ciliary body, and part of the choroid to be infiltrated by macrophages filled with Mycobacterium leprae. The walls of blood vessels in the sclera, ciliary body and the anterior choroid demonstrated the presence of M. leprae, giving credence to the blood-borne entry of M. leprae into the eye. Unlike the eyes of experimental animals infected with M. leprae, histopathological study of this eye from a lepromatous leprosy patient demonstrated that M. leprae, although demonstrable in the anterior choroid, could not be found in the posterior parts of the eye, substantiating the claim that leprosy does not affect the posterior parts of the eye directly. PMID:10834066

  5. [Dry eye syndrome. Occupational risk factors, valuation and prevention].

    PubMed

    Vicente-Herrero, M T; Ramírez-Iñiguez de la Torre, M V; Terradillos-García, M J; López González, Á A

    2014-03-01

    Dry eye syndrome in the workplace is associated with new ways of working, with increasing use of screens and electronic devices and environmental conditions encountered in modern office designs and other environments. Also affect occupational exposure to ionizing radiation, chemicals or atmospheric dust with increased ocular dryness. The study of pathophysiological aspects and laboral causality of the dry eye, must be to develop joint task in Occupational Health, Public Health in coordination with and responsible for the national health system, which would involve primary and secondary preventive measures more effective and proper diagnosis, control and monitoring of the disease, A better knowledge of occupational hazards and actions agreed and coordinated between occupational physicians, preventers, primary care physicians and specialist physicians, such as ophthalmology, will get results much more effective when earlier and optimize available resources. PMID:23993023

  6. Robotically enhanced rubber hand illusion.

    PubMed

    Arata, Jumpei; Hattori, Masashi; Ichikawa, Shohei; Sakaguchi, Masamichi

    2014-01-01

    The rubber hand illusion is a well-known multisensory illusion. In brief, watching a rubber hand being stroked by a paintbrush while one's own unseen hand is synchronously stroked causes the rubber hand to be attributed to one's own body and to "feel like it's my hand." The rubber hand illusion is thought to be triggered by the synchronized tactile stimulation of both the subject's hand and the fake hand. To extend the conventional rubber hand illusion, we introduce robotic technology in the form of a master-slave telemanipulator. The developed one degree-of-freedom master-slave system consists of an exoskeleton master equipped with an optical encoder that is worn on the subject's index finger and a motor-actuated index finger on the rubber hand, which allows the subject to perform unilateral telemanipulation. The moving rubber hand illusion has been studied by several researchers in the past with mechanically connected rigs between the subject's body and the fake limb. The robotic instruments let us investigate the moving rubber hand illusion with less constraints, thus behaving closer to the classic rubber hand illusion. In addition, the temporal delay between the body and the fake limb can be precisely manipulated. The experimental results revealed that the robotic instruments significantly enhance the rubber hand illusion. The time delay is significantly correlated with the effect of the multisensory illusion, and the effect significantly decreased at time delays over 100 ms. These findings can potentially contribute to the investigations of neural mechanisms in the field of neuroscience and of master-slave systems in the field of robotics. PMID:25532152

  7. An Armrest is Effective for Reducing Hand Tremble in Neurosurgeons

    PubMed Central

    HARA, Yosuke; GOTO, Tetsuya; OKAMOTO, Jun; OKUDA, Hideki; ISEKI, Hiroshi; HONGO, Kazuhiro

    2015-01-01

    Experienced neurosurgeons reduce hand tremble by placing their hand beside the operative field when performing microneurosurgery conventionally. Another solution to reduce hand tremble is an armrest. However, the reduction of hand tremble by using an armrest or finger-placing technique has not been rigorously measured in microneurosurgery. This study was performed to provide a quantitative assessment of the efficacy of an armrest to reduce hand tremble in comparison with the finger-placing technique. Hand tremble was evaluated in 11 board-certified neurosurgeons in a simulated microneurosurgery. The loci of surgical forceps handled by neurosurgeons were measured by a three-dimensional optical coordinate measuring machine. A static task was performed under four conditions: with/without the finger-placing technique and/or an armrest. The radius of an imaginative sphere including 95% of each locus was calculated and reviewed according to the four conditions. Hand tremble was significantly larger when the finger-placing technique was not implemented compared to when the technique was used (P < 0.05). The armrest also reduced hand tremble (P < 0.05) similar to the finger-placing technique. Non-inferiority was retained between the finger-placing technique and the armrest. Concomitant use of the armrest and the finger-placing technique did not interfere with the efficacy of the technique to reduce neurosurgeon’s hand tremble. The finger-placing technique was confirmed to reduce hand tremble. Resting the neurosurgeon’s forearm on an armrest also reduced the hand tremble. An armrest is a device that reduces hand tremble in neurosurgeons like the finger-placing technique. PMID:25797774

  8. Aging and dry eye disease

    PubMed Central

    Ding, Juan; Sullivan, David A.

    2012-01-01

    Dry eye disease is a prevalent eye disorder that in particular affects the elderly population. One of the major causes of dry eye, meibomian gland dysfunction (MGD), shows increased prevalence with aging. MGD is caused by hyperkeratinization of the ductal epithelium of meibomian gland and reduced quantity and/or quality of meibum, the holocrine product that stabilizes and prevents the evaporation of the tear film. Of note, retinoids which are used in current anti-aging cosmetics may promote the development of MGD and dry eye disease. In this review, we will discuss the possible mechanisms of age-related MGD. PMID:22569356

  9. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a springloaded plexiglass "flapper." The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  10. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a spring-loaded plexiglass 'flapper.' The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  11. An Overview of Behavioral Strategies for Reducing Hand-Related Stereotypies of Persons with Severe to Profound Intellectual and Multiple Disabilities: 1995-2007

    ERIC Educational Resources Information Center

    Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff

    2009-01-01

    This paper provides an overview of behavioral strategies used for reducing hand-related stereotypies (i.e., hand/finger mouthing, eye poking, self-slapping, and other hand-to-head/body responses) of persons with severe to profound intellectual and multiple disabilities. Computerized and manual searches were conducted to identify the studies…

  12. Explicitly computing geodetic coordinates from Cartesian coordinates

    NASA Astrophysics Data System (ADS)

    Zeng, Huaien

    2013-04-01

    This paper presents a new form of quartic equation based on Lagrange's extremum law and a Groebner basis under the constraint that the geodetic height is the shortest distance between a given point and the reference ellipsoid. A very explicit and concise formulae of the quartic equation by Ferrari's line is found, which avoids the need of a good starting guess for iterative methods. A new explicit algorithm is then proposed to compute geodetic coordinates from Cartesian coordinates. The convergence region of the algorithm is investigated and the corresponding correct solution is given. Lastly, the algorithm is validated with numerical experiments.

  13. Effects of antiglaucoma drugs on blood supply to eye tissues

    SciTech Connect

    Chiou, G.C.Y.; Yan, H.Y.

    1986-03-01

    Although it is essential that intraocular pressure (IOP) be reduced in glaucoma treatment, it is also vitally important to provide sufficient blood flow to eye tissues so that healthy visual field is maintained. It is possible for an agent to reduce IOP and blood supply to the eye. In that case, glaucoma appears to be under control since IOP has been reduced to within normal range yet the disease is actually progressing, causing damage to the retina, optic nerve, and other tissues. /sup 85/Sr-Microsphere technique was used to study the effects of several antiglaucoma drugs on blood supply to various eye tissues. Clearly, L-timolol, D-timolol and pilocarpine are good drugs to use in treating glaucoma because they do not reduce blood flow. On the other hand, although moperone reduced IOP effectively, it also decreased blood supply markedly. Therefore, it should not be used for the treatment of glaucoma.

  14. Evidence suggesting individual ocular motor control of each eye (muscle).

    PubMed

    Dell'Osso, L F

    1994-01-01

    populations of neurons (burst cells, neural integrator cells, etc.). The agonist muscles of each eye are usually coordinated (yoked) but may function independently if the task dictates or if binocularity did not develop. Models based on the above architecture would be robust and could duplicate the many responses (both normal and abnormal) possible from the neurophysiological system. PMID:7994479

  15. Asymptotes in Polar Coordinates.

    ERIC Educational Resources Information Center

    Fay, Temple H.

    1986-01-01

    An old way to determine asymptotes for curves described in polar coordinates is presented. Practice in solving trigonometric equations, in differentiation, and in calculating limits is involved. (MNS)

  16. Saccadic eye movements in a high-speed bimanual stacking task: changes of attentional control during learning and automatization.

    PubMed

    Foerster, Rebecca M; Carbone, Elena; Koesling, Hendrik; Schneider, Werner X

    2011-01-01

    Principles of saccadic eye movement control in the real world have been derived by the study of self-paced well-known tasks such as sandwich or tea making. Little is known whether these principles generalize to high-speed sensorimotor tasks and how they are affected by learning and automatization. In the present study, right-handers practiced the speed-stacking task in 14 consecutive daily training sessions, while their eye movements were recorded. Speed stacking is a high-speed sensorimotor task that requires grasping, moving, rotating, and placing of objects. The following main results emerged. Throughout practice, the eyes led the hands, displayed by a positive eye-hand time span. Moreover, visual information was gathered for the subsequent manual sub-action, displayed by a positive eye-hand unit span. With automatization, the eye-hand time span became shorter, yet it increased when corrected by the decreasing trial duration. In addition, fixations were mainly allocated to the goal positions of the right hand or objects in the right hand. The number of fixations decreased while the fixation rate remained constant. Importantly, all participants fixated on the same task-relevant locations in a similar scan path across training days, revealing a long-term memory-based mode of attention control after automatization of a high-speed sensorimotor task. PMID:21665985

  17. Double Eye Brow: A Rare Case Report

    PubMed Central

    Kar, Sudipta; Ghosh, Chiranjit; Bazmi, Badruddin Ahamed; Sarkar, Subrata

    2013-01-01

    Eye brows are essential for esthetic and functional purposes. Various kinds of eye brows are found in human species. Protective function is one of the important functions of eye brows. Double eye brow is a very rare condition found in human. This case report describes one of the rare cases of double eye brow. PMID:24574697

  18. Posture modulates implicit hand maps.

    PubMed

    Longo, Matthew R

    2015-11-01

    Several forms of somatosensation require that afferent signals be informed by stored representations of body size and shape. Recent results have revealed that position sense relies on a highly distorted body representation. Changes of internal hand posture produce plastic alterations of processing in somatosensory cortex. This study therefore investigated how such postural changes affect implicit body representations underlying position sense. Participants localised the knuckles and tips of each finger in external space in two postures: the fingers splayed (Apart posture) or pressed together (Together posture). Comparison of the relative locations of the judgments of each landmark were used to construct implicit maps of represented hand structure. Spreading the fingers apart produced increases in the implicit representation of hand size, with no apparent effect on hand shape. Thus, changes of internal hand posture produce rapid modulation of how the hand itself is represented, paralleling the known effects on somatosensory cortical processing. PMID:26117153

  19. Hand Anthropometry and SMS Satisfaction

    NASA Astrophysics Data System (ADS)

    Balakrishnan, Vimala; Yeow, Paul H. P.

    The effect of hand anthropometry on Short Message Service (SMS) satisfaction was investigated using structured questionnaire interviews with 110 subjects, aged between 17-25 years old. Hand size was measured to assess its effect on mobile phone design factors satisfaction whereas thumb circumference and length were measured for keypad design factors. Small hand-sized subjects were found to be more satisfied with mobile phone dimensions than large hand-sized subjects. Thumb circumference significantly affects users` satisfaction towards key size and space between keys whereas thumb length significantly affects keypad layout satisfaction. Both thumb circumference and length significantly correlate negatively with the corresponding keypad design factors. Results confirm that hand anthropometry do affect users messaging satisfaction. These findings should prove useful to mobile phone designers who could look into the possibility of designing customized mobile phones that cater to large hand and thumb sized users, so as to increase their subjective satisfaction.

  20. Strong anticipation: complexity matching in interpersonal coordination.

    PubMed

    Marmelat, Vivien; Delignières, Didier

    2012-10-01

    A subtle coordination occurs within complex systems, between multiple nested sub-systems. This intra-system coordination can be detected by the presence of 1/f fluctuations produced by the system. But coordination can occur also between systems. Interpersonal coordination has been studied from a local point of view until now, focusing on macroscopic interactions. But the recent concept of strong anticipation introduced by Dubois (Lect Notes Comput Sci 2684:110-132, 2003) suggests that interactions could occur on multiple levels between complex systems. The hypothesis is that time series in interpersonal synchronization present a matching of the complexity index (fractal exponent). Moreover, it is argued that this matching is not a consequence of short-term adaptations but reveals a global coordination between participants. Eleven pairs of participants oscillated a hand-held pendulum in the in-phase pattern for 11 min, in three conditions where the coupling strength was manipulated by the perceptual feedbacks. The results show a high correlation between fractal exponents irrespective of the coupling strength, and a very low percentage of local cross-correlations between time series appear at lag 0 and lag 1. These results suggest that interpersonal coordination, and more globally synchronization of participants with natural environments, is based on non-local time scales. PMID:22865163

  1. Wavefront Derived Refraction and Full Eye Biometry in Pseudophakic Eyes

    PubMed Central

    Mao, Xinjie; Banta, James T.; Ke, Bilian; Jiang, Hong; He, Jichang; Liu, Che; Wang, Jianhua

    2016-01-01

    Purpose To assess wavefront derived refraction and full eye biometry including ciliary muscle dimension and full eye axial geometry in pseudophakic eyes using spectral domain OCT equipped with a Shack-Hartmann wavefront sensor. Methods Twenty-eight adult subjects (32 pseudophakic eyes) having recently undergone cataract surgery were enrolled in this study. A custom system combining two optical coherence tomography systems with a Shack-Hartmann wavefront sensor was constructed to image and monitor changes in whole eye biometry, the ciliary muscle and ocular aberration in the pseudophakic eye. A Badal optical channel and a visual target aligning with the wavefront sensor were incorporated into the system for measuring the wavefront-derived refraction. The imaging acquisition was performed twice. The coefficients of repeatability (CoR) and intraclass correlation coefficient (ICC) were calculated. Results Images were acquired and processed successfully in all patients. No significant difference was detected between repeated measurements of ciliary muscle dimension, full-eye biometry or defocus aberration. The CoR of full-eye biometry ranged from 0.36% to 3.04% and the ICC ranged from 0.981 to 0.999. The CoR for ciliary muscle dimensions ranged from 12.2% to 41.6% and the ICC ranged from 0.767 to 0.919. The defocus aberrations of the two measurements were 0.443 ± 0.534 D and 0.447 ± 0.586 D and the ICC was 0.951. Conclusions The combined system is capable of measuring full eye biometry and refraction with good repeatability. The system is suitable for future investigation of pseudoaccommodation in the pseudophakic eye. PMID:27010674

  2. LRP predicts smooth pursuit eye movement onset during the ocular tracking of self-generated movements.

    PubMed

    Chen, Jing; Valsecchi, Matteo; Gegenfurtner, Karl R

    2016-07-01

    Several studies have indicated that human observers are very efficient at tracking self-generated hand movements with their gaze, yet it is not clear whether this is simply a by-product of the predictability of self-generated actions or if it results from a deeper coupling of the somatomotor and oculomotor systems. In a first behavioral experiment we compared pursuit performance as observers either followed their own finger or tracked a dot whose motion was externally generated but mimicked their finger motion. We found that even when the dot motion was completely predictable in terms of both onset time and kinematics, pursuit was not identical to that produced as the observers tracked their finger, as evidenced by increased rate of catch-up saccades and by the fact that in the initial phase of the movement gaze was lagging behind the dot, whereas it was ahead of the finger. In a second experiment we recorded EEG in the attempt to find a direct link between the finger motor preparation, indexed by the lateralized readiness potential (LRP) and the latency of smooth pursuit. After taking into account finger movement onset variability, we observed larger LRP amplitudes associated with earlier smooth pursuit onset across trials. The same held across subjects, where average LRP onset correlated with average eye latency. The evidence from both experiments concurs to indicate that a strong coupling exists between the motor systems leading to eye and finger movements and that simple top-down predictive signals are unlikely to support optimal coordination. PMID:27009159

  3. Multi-fingered robotic hand

    NASA Technical Reports Server (NTRS)

    Ruoff, Carl F. (Inventor); Salisbury, Kenneth, Jr. (Inventor)

    1990-01-01

    A robotic hand is presented having a plurality of fingers, each having a plurality of joints pivotally connected one to the other. Actuators are connected at one end to an actuating and control mechanism mounted remotely from the hand and at the other end to the joints of the fingers for manipulating the fingers and passing externally of the robot manipulating arm in between the hand and the actuating and control mechanism. The fingers include pulleys to route the actuators within the fingers. Cable tension sensing structure mounted on a portion of the hand are disclosed, as is covering of the tip of each finger with a resilient and pliable friction enhancing surface.

  4. Hand controller commonality evaluation process

    NASA Technical Reports Server (NTRS)

    Stuart, Mark A.; Bierschwale, John M.; Wilmington, Robert P.; Adam, Susan C.; Diaz, Manuel F.; Jensen, Dean G.

    1990-01-01

    A hand controller evaluation process has been developed to determine the appropriate hand controller configurations for supporting remotely controlled devices. These devices include remote manipulator systems (RMS), dexterous robots, and remotely-piloted free flyers. Standard interfaces were developed to evaluate six different hand controllers in three test facilities including dynamic computer simulations, kinematic computer simulations, and physical simulations. The hand controllers under consideration were six degree-of-freedom (DOF) position and rate minimaster and joystick controllers, and three-DOF rate controllers. Task performance data, subjective comments, and anthropometric data obtained during tests were used for controller configuration recommendations to the SSF Program.

  5. Stery-hand: A new device to support hand disinfection.

    PubMed

    Szilagyi, Laszlo; Lehotsky, Akos; Nagy, Melinda; Haidegger, Tamas; Benyo, Balazs; Benyo, Zoltan

    2010-01-01

    Incomplete disinfection can cause serious complications in surgical care. The teaching of effective hand washing is crucial in modern medical training. To support the objective evaluation of hand disinfection, we developed a compact, mobile device, relying on digital imaging and image processing. The hardware consists of a metal case with matte black interior, ultra-violet lighting and a digital camera. Image segmentation and clustering are performed on a regular notebook. The hand washing procedures performed with a soap mixed with UV-reflective powder. This results the skin showing bright under UV light only on the treated (sterile) surfaces. When the surgeon inserts its hands into the box, the camera placed on the top takes an image of the hand for evaluation. The software performs the segmentation and clustering automatically. First, the hand contour is determined from the green intensity channel of the recorded RGB image. Then, the pixels of the green channel belonging to the hand are partitioned to three clusters using a quick, histogram based fuzzy c-means algorithm. The optimal threshold between the intensities of clean and dirty areas is extracted using these clusters, while the final approximated percentage of the clean area is computed using a weighting formula. The main advantage of our device is the ability to obtain objective and comparable result on the quality of hand disinfection. It may find its best use in the clinical education and training. PMID:21096021

  6. Hand in Hand: Media Literacy and Internet Safety

    ERIC Educational Resources Information Center

    Gallagher, Frank

    2011-01-01

    Internet safety cannot be effectively taught without also teaching media literacy. The two go hand in hand, and both are necessary, but neither is sufficient. To understand why, it is important to first appreciate what the real risks to children are. Many of the early Internet safety programs were based on a fear of predators. Predators turned out…

  7. Self-inflicted eye injuries.

    PubMed Central

    Brown, R; al-Bachari, M A; Kambhampati, K K

    1991-01-01

    Five cases of self-inflicted eye injury are described and discussed. A review of the literature shows that several psychiatric diagnoses have been assigned to people who damage their eyes. A variety of mechanisms to explain this phenomenon are described. PMID:1873272

  8. Miniature curved artificial compound eyes

    PubMed Central

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L’Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A.; Franceschini, Nicolas

    2013-01-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  9. Miniature curved artificial compound eyes.

    PubMed

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L'Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A; Franceschini, Nicolas

    2013-06-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  10. Photographic Screening for Eye Defects

    NASA Technical Reports Server (NTRS)

    Richardson, J.

    1985-01-01

    Images of retinas examined for characteristic patterns. Color photographs of retinas taken. Proper alinement of eye obtained by asking subject to gaze at light-emitting diode. "Red-eye" patterns in resulting color photographs examined by trained observers for signs of ocular defects. System used to check power of contact lenses and eyeglasses by taking photographs with these items in place.

  11. Eye Injuries Can Be Prevented.

    ERIC Educational Resources Information Center

    PTA Today, 1987

    1987-01-01

    Eleven thousand eye injuries are suffered annually by 5- to-14-year-old youngsters during sports and recreational activities. Baseball-related accidents result in more eye injuries to youth than any other sport. Protective face gear is discussed and recommended. (MT)

  12. Dry eye disease after LASIK

    PubMed Central

    Ţuru, L; Alexandrescu, C; Stana, D; Tudosescu, R

    2012-01-01

    LASIK is a surgical tehnique for the correction of refractive errors (myopia, hyperopia, astygmatism). It results in a reshape of the cornea with ocular surface and especially tear film disease. It is a cause for a iatrogenic dry eye syndrome. Neurogenic and inflamatory theory explain this disease. The main therapy of dry eye is the replacement with artificial tears. PMID:22574092

  13. Penetrating eye injury in war.

    PubMed

    Biehl, J W; Valdez, J; Hemady, R K; Steidl, S M; Bourke, D L

    1999-11-01

    The percentage of penetrating eye injuries in war has increased significantly in this century compared with the total number of combat injuries. With the increasing use of fragmentation weapons and possibly laser weapons on the battle-field in the future, the rate of eye injuries may exceed the 13% of the total military injuries found in Operations Desert Storm/Shield. During the Iran-Iraq War (1980-1988), eye injuries revealed that retained foreign bodies and posterior segment injuries have an improved prognosis in future military ophthalmic surgery as a result of modern diagnostic and treatment modalities. Compared with the increasing penetrating eye injuries on the battlefield, advances in ophthalmic surgery are insignificant. Eye armor, such as visors that flip up and down and protect the eyes from laser injury, needs to be developed. Similar eye protection is being developed in civilian sportswear. Penetrating eye injury in the civilian sector is becoming much closer to the military model and is now comparable for several reasons. PMID:10578588

  14. Microoptical telescope compound eye

    NASA Astrophysics Data System (ADS)

    Duparré, Jacques W.; Schreiber, Peter; Matthes, André; Pshenay–Severin, Ekaterina; Bräuer, Andreas; Tünnermann, Andreas; Völkel, Reinhard; Eisner, Martin; Scharf, Toralf

    2005-02-01

    A new optical concept for compact digital image acquisition devices with large field of view is developed and proofed experimentally. Archetypes for the imaging system are compound eyes of small insects and the Gabor Superlens. A paraxial 3x3 matrix formalism is used to describe the telescope arrangement of three microlens arrays with different pitch to find first order parameters of the imaging system. A 2mm thin imaging system with 21x3 channels, 70ºx10º field of view and 4.5mm x 0.5mm image size is optimized and analyzed using sequential and non sequential raytracing and fabricated by microoptics technology. Anamorphic lenses, where the parameters are a function of the considered optical channel, are used to achieve a homogeneous optical performance over the whole field of view. Captured images are presented and compared to simulation results.

  15. Microoptical telescope compound eye.

    PubMed

    Duparré, Jacques; Schreiber, Peter; Matthes, André; Pshenay-Severin, Ekaterina; Bräuer, Andreas; Tünnermann, Andreas; Völkel, Reinhard; Eisner, Martin; Scharf, Toralf

    2005-02-01

    A new optical concept for compact digital image acquisition devices with large field of view is developed and proofed experimentally. Archetypes for the imaging system are compound eyes of small insects and the Gabor-Superlens. A paraxial 3x3 matrix formalism is used to describe the telescope arrangement of three microlens arrays with different pitch to find first order parameters of the imaging system. A 2mm thin imaging system with 21x3 channels, 70 masculinex10 masculine field of view and 4.5mm x 0.5mm image size is optimized and analyzed using sequential and non-sequential raytracing and fabricated by microoptics technology. Anamorphic lenses, where the parameters are a function of the considered optical channel, are used to achieve a homogeneous optical performance over the whole field of view. Captured images are presented and compared to simulation results. PMID:19494951

  16. [Diabetic eye disease].

    PubMed

    Henriques, José; Vaz-Pereira, Sara; Nascimento, João; Rosa, Paulo Caldeira

    2015-01-01

    Diabetes mellitus is a chronic metabolic disease characterized by sustained hyperglycemia leading to macro and microvascular complications. The eye is one of the main organs affected by this disease, being diabetic retinopathy the most well-known microvascular complication and the leading cause of blindness in the working age population. However, diabetic ocular disease is not only characterized by diabetic retinopathy. Other important ocular manifestations of diabetes mellitus include cataract, glaucoma, ischemic optic neuropathy, cranial nerve palsies and recurrent corneal erosion syndrome. Here, we emphasize diabetic retinopathy as the most important and characteristic complication of diabetes mellitus, but also review less well-known complications with the aim to alert and sensitize non-ophthalmologist clinicians that treat diabetic individuals, in order to promote an early diagnosis and treatment of the sight-threatening complications of diabetes. PMID:25817504

  17. Eyes of Ganges

    NASA Technical Reports Server (NTRS)

    2005-01-01

    21 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded, light-toned layered rock outcrops on the side of a large mound in Ganges Chasma, part of the vast Valles Marineris trough system. Perhaps a testament to the inherent human (and primate) ability to pick out faces where partially hidden from view (even when a face is not really there) -- near the top of this picture are two features, each a product of erosion, resembling a pair of human eyes. This picture was acquired in late November 2005.

    Location near: 7.1oS, 49.4oW Image width: width: 0.55 km (0.3 mi) Illumination from: left/lower left Season: Southern Summer

  18. Quantification of vestibular-induced eye movements in zebrafish larvae

    PubMed Central

    2010-01-01

    Background Vestibular reflexes coordinate movements or sensory input with changes in body or head position. Vestibular-evoked responses that involve the extraocular muscles include the vestibulo-ocular reflex (VOR), a compensatory eye movement to stabilize retinal images. Although an angular VOR attributable to semicircular canal stimulation was reported to be absent in free-swimming zebrafish larvae, recent studies reveal that vestibular-induced eye movements can be evoked in zebrafish larvae by both static tilts and dynamic rotations that tilt the head with respect to gravity. Results We have determined herein the basis of sensitivity of the larval eye movements with respect to vestibular stimulus, developmental stage, and sensory receptors of the inner ear. For our experiments, video recordings of larvae rotated sinusoidally at 0.25 Hz were analyzed to quantitate eye movements under infrared illumination. We observed a robust response that appeared as early as 72 hours post fertilization (hpf), which increased in amplitude over time. Unlike rotation about an earth horizontal axis, rotation about an earth vertical axis at 0.25 Hz did not evoke eye movements. Moreover, vestibular-induced responses were absent in mutant cdh23 larvae and larvae lacking anterior otoliths. Conclusions Our results provide evidence for a functional vestibulo-oculomotor circuit in 72 hpf zebrafish larvae that relies upon sensory input from anterior/utricular otolith organs. PMID:20815905

  19. Dynamic Hand Gesture Recognition Using the Skeleton of the Hand

    NASA Astrophysics Data System (ADS)

    Ionescu, Bogdan; Coquin, Didier; Lambert, Patrick; Buzuloiu, Vasile

    2005-12-01

    This paper discusses the use of the computer vision in the interpretation of human gestures. Hand gestures would be an intuitive and ideal way of exchanging information with other people in a virtual space, guiding some robots to perform certain tasks in a hostile environment, or interacting with computers. Hand gestures can be divided into two main categories: static gestures and dynamic gestures. In this paper, a novel dynamic hand gesture recognition technique is proposed. It is based on the 2D skeleton representation of the hand. For each gesture, the hand skeletons of each posture are superposed providing a single image which is the dynamic signature of the gesture. The recognition is performed by comparing this signature with the ones from a gesture alphabet, using Baddeley's distance as a measure of dissimilarities between model parameters.

  20. Laser light scattering in eye lens model

    NASA Astrophysics Data System (ADS)

    Larionova, Nadezhda L.; Maksimova, Irina L.; Kochubey, Vyacheslav I.

    2000-11-01

    Theoretical investigations of laser light radiation scattered by eye lens model as a system of spheres with various parameters were performed on the base of Mie theory of electromagnetic scattering by a single sphere. The calculations were performed for systems of particles whose coordinates were specifically realized in random fashion according to the specified probabilities defined by the approximation of hard spheres. The modeling of lens biotissue was carried out by using of medical data about internal structure of lens of human and some animals. In general the researchable model presents the system of homogeneous spherical particles those are randomly distributed in the layer of thickness. We study the optical properties such as scattering effective cross-section and function of correlation in different models.

  1. Social Postural Coordination

    ERIC Educational Resources Information Center

    Varlet, Manuel; Marin, Ludovic; Lagarde, Julien; Bardy, Benoit G.

    2011-01-01

    The goal of the current study was to investigate whether a visual coupling between two people can produce spontaneous interpersonal postural coordination and change their intrapersonal postural coordination involved in the control of stance. We examined the front-to-back head displacements of participants and the angular motion of their hip and…

  2. IVS Technology Coordinator Report

    NASA Technical Reports Server (NTRS)

    Whitney, Alan

    2013-01-01

    This report of the Technology Coordinator includes the following: 1) continued work to implement the new VLBI2010 system, 2) the 1st International VLBI Technology Workshop, 3) a VLBI Digital- Backend Intercomparison Workshop, 4) DiFX software correlator development for geodetic VLBI, 5) a review of progress towards global VLBI standards, and 6) a welcome to new IVS Technology Coordinator Bill Petrachenko.

  3. Team coordination dynamics.

    PubMed

    Gorman, Jamie C; Amazeen, Polemnia G; Cooke, Nancy J

    2010-07-01

    Team coordination consists of both the dynamics of team member interaction and the environmental dynamics to which a team is subjected. Focusing on dynamics, an approach is developed that contrasts with traditional aggregate-static concepts of team coordination as characterized by the shared mental model approach. A team coordination order parameter was developed to capture momentary fluctuations in coordination. Team coordination was observed in three-person uninhabited air vehicle teams across two experimental sessions. The dynamics of the order parameter were observed under changes of a team familiarity control parameter. Team members returned for the second session to either the same (Intact) or different (Mixed) team. 'Roadblock' perturbations, or novel changes in the task environment, were introduced in order to probe the stability of team coordination. Nonlinear dynamic methods revealed differences that a traditional approach did not: Intact and Mixed team coordination dynamics looked very different; Mixed teams were more stable than Intact teams and explored the space of solutions without the need for correction. Stability was positively correlated with the number of roadblock perturbations that were overcome successfully. The novel and non-intuitive contribution of a dynamical analysis was that Mixed teams, who did not have a long history working together, were more adaptive. Team coordination dynamics carries new implications for traditional problems such as training adaptive teams. PMID:20587302

  4. 6. Coordination and control.

    PubMed

    2014-05-01

    Any complex operation requires a system for management. In most societies, disaster management is the responsibility of the government. Coordination and control is a system that provides the oversight for all of the disaster management functions. The roles and responsibilities of a coordination and control centre include: (1) planning; (2) maintenance of inventories; (3) activation of the disaster response plan; (4) application of indicators of function; (5) surveillance; (6) information management; (7) coordination of activities of the BSFs; (8) decision-making; (9) priority setting; (10) defining overarching goal and objectives for interventions; (11) applying indicators of effectiveness; (12) applying indicators of benefit and impact; (13) exercising authority; (14) managing resources; (15) initiating actions; (16) preventing influx of unneeded resources; (17) defining progress; (18) providing information; (19) liasing with responding organisations; and (20) providing quality assurance. Coordination and control is impossible without communications. To accomplish coordination and control, three factors must be present: (1) mandate; (2) power and authority; and (3) available resources. Coordination and control is responsible for the evaluation of the effectiveness and benefits/impacts of all interventions. Coordination and control centres (CCCs) are organised hierarchically from the on-scene CCCs (incident command) to local provincial to national CCCs. Currently, no comprehensive regional and international CCCs have been universally endorsed. Systems such as the incident command system, the unified command system, and the hospital incident command system are described as are the humanitarian reform movement and the importance of coordination and control in disaster planning and preparedness. PMID:24785803

  5. Evaluation of the Painful Eye.

    PubMed

    Pflipsen, Matthew; Massaquoi, Mariama; Wolf, Suzanne

    2016-06-15

    Eye problems constitute 2% to 3% of all primary care and emergency department visits. Common eye conditions that can cause eye pain are conjunctivitis, corneal abrasion, and hordeolum, and some of the most serious eye conditions include acute angle-closure glaucoma, orbital cellulitis, and herpetic keratitis. The history should focus on vision changes, foreign body sensation, photophobia, and associated symptoms, such as headache. The physical examination includes an assessment of visual acuity and systematic evaluation of the conjunctiva, eyelids, sclera, cornea, pupil, anterior chamber, and anterior uvea. Further examination with fluorescein staining and tonometry is often necessary. Because eye pain can be the first sign of an ophthalmologic emergency, the physician should determine if referral is warranted. Specific conditions that require ophthalmology consultation include acute angle-closure glaucoma, optic neuritis, orbital cellulitis, scleritis, anterior uveitis, and infectious keratitis. PMID:27304768

  6. A Support System for Mouse Operations Using Eye-Gaze Input

    NASA Astrophysics Data System (ADS)

    Abe, Kiyohiko; Nakayama, Yasuhiro; Ohi, Shoichi; Ohyama, Minoru

    We have developed an eye-gaze input system for people with severe physical disabilities, such as amyotrophic lateral sclerosis (ALS) patients. This system utilizes a personal computer and a home video camera to detect eye-gaze under natural light. The system detects both vertical and horizontal eye-gaze by simple image analysis, and does not require special image processing units or sensors. Our conventional eye-gaze input system can detect horizontal eye-gaze with a high degree of accuracy. However, it can only classify vertical eye-gaze into 3 directions (up, middle and down). In this paper, we propose a new method for vertical eye-gaze detection. This method utilizes the limbus tracking method for vertical eye-gaze detection. Therefore our new eye-gaze input system can detect the two-dimension coordinates of user's gazing point. By using this method, we develop a new support system for mouse operation. This system can move the mouse cursor to user's gazing point.

  7. Predictive eye movements in natural vision

    PubMed Central

    McKinney, Travis; Chajka, Kelly; Pelz, Jeff B.

    2012-01-01

    In the natural world, the brain must handle inherent delays in visual processing. This is a problem particularly during dynamic tasks. A possible solution to visuo-motor delays is prediction of a future state of the environment based on the current state and properties of the environment learned from experience. Prediction is well known to occur in both saccades and pursuit movements and is likely to depend on some kind of internal visual model as the basis for this prediction. However, most evidence comes from controlled laboratory studies using simple paradigms. In this study, we examine eye movements made in the context of demanding natural behavior, while playing squash. We show that prediction is a pervasive component of gaze behavior in this context. We show in addition that these predictive movements are extraordinarily precise and operate continuously in time across multiple trajectories and multiple movements. This suggests that prediction is based on complex dynamic visual models of the way that balls move, accumulated over extensive experience. Since eye, head, arm, and body movements all co-occur, it seems likely that a common internal model of predicted visual state is shared by different effectors to allow flexible coordination patterns. It is generally agreed that internal models are responsible for predicting future sensory state for control of body movements. The present work suggests that model-based prediction is likely to be a pervasive component in natural gaze control as well. PMID:22183755

  8. Genetics Home Reference: fish-eye disease

    MedlinePlus

    ... Understand Genetics Home Health Conditions fish-eye disease fish-eye disease Enable Javascript to view the expand/ ... boxes. Download PDF Open All Close All Description Fish-eye disease , also called partial LCAT deficiency, is ...

  9. Listing's law for eye, head and arm movements and their synergistic control.

    PubMed

    Straumann, D; Haslwanter, T; Hepp-Reymond, M C; Hepp, K

    1991-01-01

    We have recorded eye, head, and upper arm rotations in five healthy human subjects using the three-dimensional search coil technique. Our measurements show that the coordination of eye and head movements during gaze shifts within +/- 25 deg relative to the forward direction is organized by restricting the rotatory trajectories of the two systems to almost parallel planes. These so-called "Listing planes" for eye-in-space and head-in-space rotations are workspace-oriented, not body-fixed. Eye and head trajectories in their respective planes are closely related in direction and amplitude. For pointing or grasping, the rotatory trajectories of the arm are also restricted to a workspace-oriented Listing plane. During visually guided movements, arm follows gaze, and the nine-dimensional rotatory configuration space for eye-head-arm-synergies (three degrees of freedom for each system) is reduced to a two-dimensional plane in the space of quaternion vectors. PMID:1756791

  10. Gage for evaluating rheumatoid hands

    NASA Technical Reports Server (NTRS)

    Houge, J. C.; Plautz, K. A.

    1981-01-01

    Two-axis goniometer accurately measures movements of fingers about knuckle joints, diagnosing hands structurally changed by rheumatoid arthritis. Instrument measures lateral movement which is small in normal knuckles but increased in diseased joints. Goniometer is two connected protractors that simultaneously measure angles in perpindicular planes. Dials are offset to clear bony protuberances; extension and offset adjustments span any hand size.

  11. Handwashing: Clean Hands Save Lives

    MedlinePlus

    ... and what you can do if soap and clean, running water are not available. Whether you are at home, at work, traveling, or already sick, find out how good hand hygiene can protect you, your family, and others. More… Featured Video Keeping our hands clean is one of the best things we can ...

  12. Robot Forearm and Dexterous Hand

    NASA Technical Reports Server (NTRS)

    Lovchik, Christopher S.

    2005-01-01

    An electromechanical hand-and-forearm assembly has been developed for incorporation into an anthropomorphic robot that would be used in outer space. The assembly is designed to offer manual dexterity comparable to that of a hand inside an astronaut s suit; thus, the assembly may also be useful as a prosthesis or as an end effector on an industrial robot.

  13. Hand controller commonality evaluation process

    NASA Technical Reports Server (NTRS)

    Stuart, Mark A.; Bierschwale, John M.; Wilmington, Robert P.; Adam, Susan C.; Diaz, Manuel F.; Jensen, Dean G.

    1993-01-01

    Hand controller selection for NASA's Orbiter and Space Station Freedom is an important area of human-telerobot interface design and evaluation. These input devices will control remotely operated systems that include large crane-like manipulators (e.g., Remote Manipulator System or RMS), smaller, more dexterous manipulators (e.g., Flight Telerobotic Servicer or FTS), and free flyers (e.g., Orbital Maneuvering Vehicle or OMV). Candidate hand controller configurations for these systems vary in many ways: shape, size, number of degrees-of-freedom (DOF), operating modes, provision of force reflection, range of movement, and 'naturalness' of use. Unresolved design implementation issues remain, including such topics as how the current Orbiter RMS rotational and translational rate hand controllers compare with the proposed Space Station Freedom hand controllers, the advantages that position hand controllers offer for these applications, and whether separate hand controller configurations are required for each application. Since previous studies contain little empirical hand controller task performance data, a controlled study is needed that tests Space Station Freedom candidate hand controllers during representative tasks. This study also needs to include anthropometric and biomechanical considerations.

  14. The Work of the Hand

    ERIC Educational Resources Information Center

    Ludick, Pat

    2013-01-01

    Recognizing Maria and Mario Montessori's reverence for the hand, Pat Ludick takes the reader into the wonder of the human body, mind, and spirit and across the planes of education, into the making of a whole personality and grounded intelligence that is ready for the adult world. Putting the hand front and center, she lyrically evolves an overview…

  15. The Left-Handed Writer.

    ERIC Educational Resources Information Center

    Bloodsworth, James Gaston

    Contrary to the beliefs of many, right-handedness is not a single factor existing in almost all people, with a few exceptions termed left-handed: neither extreme exists independently of the other. During the first 4 years of life there is a period of fluctuation between right and left-handed dominance. Statistics and findings vary in determining…

  16. Coordination sequences and coordination waves in matter

    SciTech Connect

    Rau, V. G. Pugaev, A. A.; Rau, T. F.

    2006-01-15

    A possible way of partitioning a space into polycubes (n-dimensional modifications of Golomb polyominoes, which are generally nonconvex) is used as a basic model of ordered matter structure. It is suggested that layer-by-layer growth of a structure, occurring along the geodetics of the digraph of a net defined by the local rules of bonding of polycubes, justifies the phenomenological laws of shaping (self-similarity during the growth, independence of the polyhedron shape on the 'seed,' the symmetry of the growth polyhedron, etc.). Specific results of the analysis of number sequences of the increase in coordination circles for planar periodic partitions of model and real crystal structures, as well as the preliminary results of investigation of standing coordination topological waves, revealed for the first time in computer experiments, are reported.

  17. The hand of Homo naledi

    PubMed Central

    Kivell, Tracy L.; Deane, Andrew S.; Tocheri, Matthew W.; Orr, Caley M.; Schmid, Peter; Hawks, John; Berger, Lee R.; Churchill, Steven E.

    2015-01-01

    A nearly complete right hand of an adult hominin was recovered from the Rising Star cave system, South Africa. Based on associated hominin material, the bones of this hand are attributed to Homo naledi. This hand reveals a long, robust thumb and derived wrist morphology that is shared with Neandertals and modern humans, and considered adaptive for intensified manual manipulation. However, the finger bones are longer and more curved than in most australopiths, indicating frequent use of the hand during life for strong grasping during locomotor climbing and suspension. These markedly curved digits in combination with an otherwise human-like wrist and palm indicate a significant degree of climbing, despite the derived nature of many aspects of the hand and other regions of the postcranial skeleton in H. naledi. PMID:26441219

  18. The hand of Homo naledi.

    PubMed

    Kivell, Tracy L; Deane, Andrew S; Tocheri, Matthew W; Orr, Caley M; Schmid, Peter; Hawks, John; Berger, Lee R; Churchill, Steven E

    2015-01-01

    A nearly complete right hand of an adult hominin was recovered from the Rising Star cave system, South Africa. Based on associated hominin material, the bones of this hand are attributed to Homo naledi. This hand reveals a long, robust thumb and derived wrist morphology that is shared with Neandertals and modern humans, and considered adaptive for intensified manual manipulation. However, the finger bones are longer and more curved than in most australopiths, indicating frequent use of the hand during life for strong grasping during locomotor climbing and suspension. These markedly curved digits in combination with an otherwise human-like wrist and palm indicate a significant degree of climbing, despite the derived nature of many aspects of the hand and other regions of the postcranial skeleton in H. naledi. PMID:26441219

  19. 3D Printed Robotic Hand

    NASA Technical Reports Server (NTRS)

    Pizarro, Yaritzmar Rosario; Schuler, Jason M.; Lippitt, Thomas C.

    2013-01-01

    Dexterous robotic hands are changing the way robots and humans interact and use common tools. Unfortunately, the complexity of the joints and actuations drive up the manufacturing cost. Some cutting edge and commercially available rapid prototyping machines now have the ability to print multiple materials and even combine these materials in the same job. A 3D model of a robotic hand was designed using Creo Parametric 2.0. Combining "hard" and "soft" materials, the model was printed on the Object Connex350 3D printer with the purpose of resembling as much as possible the human appearance and mobility of a real hand while needing no assembly. After printing the prototype, strings where installed as actuators to test mobility. Based on printing materials, the manufacturing cost of the hand was $167, significantly lower than other robotic hands without the actuators since they have more complex assembly processes.

  20. Eye movements in chameleons are not truly independent - evidence from simultaneous monocular tracking of two targets.

    PubMed

    Katz, Hadas Ketter; Lustig, Avichai; Lev-Ari, Tidhar; Nov, Yuval; Rivlin, Ehud; Katzir, Gadi

    2015-07-01

    Chameleons perform large-amplitude eye movements that are frequently referred to as independent, or disconjugate. When prey (an insect) is detected, the chameleon's eyes converge to view it binocularly and 'lock' in their sockets so that subsequent visual tracking is by head movements. However, the extent of the eyes' independence is unclear. For example, can a chameleon visually track two small targets simultaneously and monocularly, i.e. one with each eye? This is of special interest because eye movements in ectotherms and birds are frequently independent, with optic nerves that are fully decussated and intertectal connections that are not as developed as in mammals. Here, we demonstrate that chameleons presented with two small targets moving in opposite directions can perform simultaneous, smooth, monocular, visual tracking. To our knowledge, this is the first demonstration of such a capacity. The fine patterns of the eye movements in monocular tracking were composed of alternating, longer, 'smooth' phases and abrupt 'step' events, similar to smooth pursuits and saccades. Monocular tracking differed significantly from binocular tracking with respect to both 'smooth' phases and 'step' events. We suggest that in chameleons, eye movements are not simply 'independent'. Rather, at the gross level, eye movements are (i) disconjugate during scanning, (ii) conjugate during binocular tracking and (iii) disconjugate, but coordinated, during monocular tracking. At the fine level, eye movements are disconjugate in all cases. These results support the view that in vertebrates, basic monocular control is under a higher level of regulation that dictates the eyes' level of coordination according to context. PMID:26157161

  1. Endophthalmitis after tooth extraction in a patient with previous perforating eye injury.

    PubMed

    Ogurel, Tevfik; Onaran, Zafer; Ogurel, Reyhan; Örnek, Kemal

    2015-01-01

    The aim of this stuty is to describe a case of endophthalmitis after tooth extraction in a patient with previous perforating eye injury. 50 years old male patient attempted to our clinic with complaints of sudden severe pain, reduced vision, light sensitivity and redness in the right eye. The patient stated that severe pain in his eye began approximately 12 hours following tooth extraction. The patient's ocular examination revealed a visual acuity of hand motion in the right eye. Anterior segment examination of the right eye showed intense conjunctival hyperemia, chemosis, a fine keraticprespitat and corneal edema. Dental procedures of the patients who had recently underwent ocular surgery or trauma should be done in a more controlled manner under anti -infective therapy or should be postponed in elective procedures. PMID:26090030

  2. Arousal facilitates involuntary eye movements.

    PubMed

    DiGirolamo, Gregory J; Patel, Neha; Blaukopf, Clare L

    2016-07-01

    Attention plays a critical role in action selection. However, the role of attention in eye movements is complicated as these movements can be either voluntary or involuntary, with, in some circumstances (antisaccades), these two actions competing with each other for execution. But attending to the location of an impending eye movement is only one facet of attention that may play a role in eye movement selection. In two experiments, we investigated the effect of arousal on voluntary eye movements (antisaccades) and involuntary eye movements (prosaccadic errors) in an antisaccade task. Arousal, as caused by brief loud sounds and indexed by changes in pupil diameter, had a facilitation effect on involuntary eye movements. Involuntary eye movements were both significantly more likely to be executed and significantly faster under arousal conditions (Experiments 1 and 2), and the influence of arousal had a specific time course (Experiment 2). Arousal, one form of attention, can produce significant costs for human movement selection as potent but unplanned actions are benefited more than planned ones. PMID:26928432

  3. Lenses matching of compound eye for target positioning

    NASA Astrophysics Data System (ADS)

    Guo, Fang; Zheng, Yan Pei; Wang, Keyi

    2012-10-01

    Compound eye, as a new imaging method with multi-lens for a large field of view, could complete target positioning and detection fastly, especially at close range. Therefore it could be applicated in the fields of military and medical treatment and aviation with vast market potential and development prospect. Yet the compound eye imaging method designed use three layer construction of multiple lens array arranged in a curved surface and refractive lens and imaging sensor of CMOS. In order to simplify process structure and increase the imaging area of every sub-eye, the imaging area of every eye is coved with the whole CMOS. Therefore, for several imaging point of one target, the corresponding lens of every imaging point is unkonown, and thus to identify. So an algorithm was put forward. Firstly, according to the Regular Geometry relationship of several adjacent lenses, data organization of seven lenses with a main lens was built. Subsequently, by the data organization, when one target was caught by several unknown lenses, we search every combined type of the received lenses. And for every combined type, two lenses were selected to combine and were used to calculate one three-dimensional (3D) coordinate of the target. If the 3D coordinates are same to the some combine type of the lenses numbers, in theory, the lenses and the imaging points are matched. So according to error of the 3D coordinates is calculated by the different seven lenses numbers combines, the unknown lenses could be distinguished. The experimental results show that the presented algorithm is feasible and can complete matching task for imaging points and corresponding lenses.

  4. Virtual Partner Interaction (VPI): exploring novel behaviors via coordination dynamics.

    PubMed

    Kelso, J A Scott; de Guzman, Gonzalo C; Reveley, Colin; Tognoli, Emmanuelle

    2009-01-01

    Inspired by the dynamic clamp of cellular neuroscience, this paper introduces VPI -- Virtual Partner Interaction -- a coupled dynamical system for studying real time interaction between a human and a machine. In this proof of concept study, human subjects coordinate hand movements with a virtual partner, an avatar of a hand whose movements are driven by a computerized version of the Haken-Kelso-Bunz (HKB) equations that have been shown to govern basic forms of human coordination. As a surrogate system for human social coordination, VPI allows one to examine regions of the parameter space not typically explored during live interactions. A number of novel behaviors never previously observed are uncovered and accounted for. Having its basis in an empirically derived theory of human coordination, VPI offers a principled approach to human-machine interaction and opens up new ways to understand how humans interact with human-like machines including identification of underlying neural mechanisms. PMID:19492044

  5. Virtual Partner Interaction (VPI): Exploring Novel Behaviors via Coordination Dynamics

    PubMed Central

    Kelso, J. A. Scott; de Guzman, Gonzalo C.; Reveley, Colin; Tognoli, Emmanuelle

    2009-01-01

    Inspired by the dynamic clamp of cellular neuroscience, this paper introduces VPI—Virtual Partner Interaction—a coupled dynamical system for studying real time interaction between a human and a machine. In this proof of concept study, human subjects coordinate hand movements with a virtual partner, an avatar of a hand whose movements are driven by a computerized version of the Haken-Kelso-Bunz (HKB) equations that have been shown to govern basic forms of human coordination. As a surrogate system for human social coordination, VPI allows one to examine regions of the parameter space not typically explored during live interactions. A number of novel behaviors never previously observed are uncovered and accounted for. Having its basis in an empirically derived theory of human coordination, VPI offers a principled approach to human-machine interaction and opens up new ways to understand how humans interact with human-like machines including identification of underlying neural mechanisms. PMID:19492044

  6. [Eye Myiasis - a Case Report].

    PubMed

    Kopecký, A; Němčanský, J; Doležil, Z; Mašková, R; Mašek, P

    2015-09-01

    The authors describe a case of 47 years old patient who came to the department of ophthalmology with eye discomfort, ear bleeding and itching of both legs. The diagnosis of ophthalmomyiasis was made after an eye examination. Manual extraction of maggots from upper and lower fornix of the left eye was performed and symptomatic therapy was given. The patient was sent to otolaryngology and dermatology departments and MRI. The maggots were also found in both external auditory meatus and between the toes. MRI excluded affection of the deeper structures of the head. Improvement of the local condition was observed since the first follow-up visit. PMID:26782730

  7. The Marble-Hand Illusion

    PubMed Central

    Senna, Irene; Maravita, Angelo; Bolognini, Nadia; Parise, Cesare V.

    2014-01-01

    Our body is made of flesh and bones. We know it, and in our daily lives all the senses constantly provide converging information about this simple, factual truth. But is this always the case? Here we report a surprising bodily illusion demonstrating that humans rapidly update their assumptions about the material qualities of their body, based on their recent multisensory perceptual experience. To induce a misperception of the material properties of the hand, we repeatedly gently hit participants' hand with a small hammer, while progressively replacing the natural sound of the hammer against the skin with the sound of a hammer hitting a piece of marble. After five minutes, the hand started feeling stiffer, heavier, harder, less sensitive, unnatural, and showed enhanced Galvanic skin response (GSR) to threatening stimuli. Notably, such a change in skin conductivity positively correlated with changes in perceived hand stiffness. Conversely, when hammer hits and impact sounds were temporally uncorrelated, participants did not spontaneously report any changes in the perceived properties of the hand, nor did they show any modulation in GSR. In two further experiments, we ruled out that mere audio-tactile synchrony is the causal factor triggering the illusion, further demonstrating the key role of material information conveyed by impact sounds in modulating the perceived material properties of the hand. This novel bodily illusion, the ‘Marble-Hand Illusion', demonstrates that the perceived material of our body, surely the most stable attribute of our bodily self, can be quickly updated through multisensory integration. PMID:24621793

  8. Eyes in the Sky

    NASA Technical Reports Server (NTRS)

    2006-01-01

    These shape-shifting galaxies have taken on the form of a giant mask. The icy blue eyes are actually the cores of two merging galaxies, called NGC 2207 and IC 2163, and the mask is their spiral arms. The false-colored image consists of infrared data from NASA's Spitzer Space Telescope (red) and visible data from NASA's Hubble Space Telescope (blue/green).

    NGC 2207 and IC 2163 met and began a sort of gravitational tango about 40 million years ago. The two galaxies are tugging at each other, stimulating new stars to form. Eventually, this cosmic ball will come to an end, when the galaxies meld into one. The dancing duo is located 140 million light-years away in the Canis Major constellation.

    The infrared data from Spitzer highlight the galaxies' dusty regions, while the visible data from Hubble indicates starlight. In the Hubble-only image (not pictured here), the dusty regions appear as dark lanes.

    The Hubble data correspond to light with wavelengths of .44 and .55 microns (blue and green, respectively). The Spitzer data represent light of 8 microns.

  9. The eyes of LITENING

    NASA Astrophysics Data System (ADS)

    Moser, Eric K.

    2016-05-01

    LITENING is an airborne system-of-systems providing long-range imaging, targeting, situational awareness, target tracking, weapon guidance, and damage assessment, incorporating a laser designator and laser range finders, as well as non-thermal and thermal imaging systems, with multi-sensor boresight. Robust operation is at a premium, and subsystems are partitioned to modular, swappable line-replaceable-units (LRUs) and shop-replaceable-units (SRUs). This presentation will explore design concepts for sensing, data storage, and presentation of imagery associated with the LITENING targeting pod. The "eyes" of LITENING are the electro-optic sensors. Since the initial LITENING II introduction to the US market in the late 90s, as the program has evolved and matured, a series of spiral functional improvements and sensor upgrades have been incorporated. These include laser-illuminated imaging, and more recently, color sensing. While aircraft displays are outside of the LITENING system, updates to the available viewing modules have also driven change, and resulted in increasingly effective ways of utilizing the targeting system. One of the latest LITENING spiral upgrades adds a new capability to display and capture visible-band color imagery, using new sensors. This is an augmentation to the system's existing capabilities, which operate over a growing set of visible and invisible colors, infrared bands, and laser line wavelengths. A COTS visible-band camera solution using a CMOS sensor has been adapted to meet the particular needs associated with the airborne targeting use case.

  10. Developmental coordination disorder

    MedlinePlus

    Physical causes and other types of learning disabilities must be ruled out before the diagnosis can be confirmed. ... Developmental coordination disorder can lead to: Learning problems ... wanting to participate in physical activities (such as sports)

  11. Developmental coordination disorder

    MedlinePlus

    Physical education and perceptual motor training (combining movement with tasks that require thinking, like math or reading) are the best ways to treat coordination disorder. Using a computer to take ...

  12. Compartment Syndrome of the Hand.

    PubMed

    Oak, Nikhil R; Abrams, Reid A

    2016-07-01

    Hand compartment syndrome has many etiologies; untreated, it has dire functional consequences. Intracompartmental pressure exceeding capillary filling pressure causes decreased tissue perfusion resulting in progressive ischemic death of compartment contents. Clinical findings can evolve. Serial physical examinations are recommended and, if equivocal, interstitial pressure monitoring is indicated. Definitive management is emergent fasciotomies with incisions designed to decompress the involved hand compartments, which could include the thenar, hypothenar, and interosseous compartments, and the carpal tunnel. Careful wound care, edema management, splinting, and hand therapy are critical. Therapy should start early postoperatively, possibly before wound closure. PMID:27241383

  13. Reversing the hands of time: changing the mapping from seeing to saying.

    PubMed

    Kuchinsky, Stefanie E; Bock, Kathryn; Irwin, David E

    2011-05-01

    To describe a scene, speakers must map visual information to a linguistic plan. Eye movements capture features of this linkage in a tendency for speakers to fixate referents just before they are mentioned. The current experiment examined whether and how this pattern changes when speakers create atypical mappings. Eye movements were monitored as participants told the time from analog clocks. Half of the participants did this in the usual manner. For the other participants, the denotations of the clock hands were reversed, making the big hand the hour and the little hand the minute. Eye movements revealed that it was not the visual features or configuration of the hands that determined gaze patterns, but rather top-down control from upcoming referring expressions. Differences in eye-voice spans further suggested a process in which scene elements are relationally structured before a linguistic plan is executed. This provides evidence for structural rather than lexical incrementality in planning and supports a "seeing-for-saying" hypothesis in which the visual system is harnessed to the linguistic demands of an upcoming utterance. PMID:21534707

  14. Luminescent lanthanide coordination polymers

    SciTech Connect

    Ma, L.; Evans, O.R.; Foxman, B.M.; Lin, W.

    1999-12-13

    One-dimensional lanthanide coordination polymers with the formula Ln(isonicotinate){sub 3}(H{sub 2}O){sub 2} (Ln = Ce, Pr, Nd, Sm, Eu, Tb; 1a-f) were synthesized by treating nitrate or perchlorate salts of Ln(III) with 4-pyridinecarboxaldehyde under hydro(solvo)thermal conditions. Single-crystal and powder X-ray diffraction studies indicate that these lanthanide coordination polymers adopt two different structures. While Ce(III), Pr(III), and Nd(III) complexes adopt a chain structure with alternating Ln-(carboxylate){sub 2}-Ln and Ln-(carboxylate){sub 4}-Ln linkages, Sm(III), Eu(III), and Tb(III) complexes have a doubly carboxylate-bridged infinite-chain structure with one chelating carboxylate group on each metal center. In both structures, the lanthanide centers also bind to two water molecules to yield an eight-coordinate, square antiprismatic geometry. The pyridine nitrogen atoms of the isonicotinate groups do not coordinate to the metal centers in these lanthanide(III) complexes; instead, they direct the formation of Ln(III) coordination polymers via hydrogen bonding with coordinated water molecules. Photoluminescence measurements show that Tb(isonicotinate){sub 3}(H{sub 2}O){sub 2} is highly emissive at room temperature with a quantum yield of {approximately}90%. These results indicate that highly luminescent lanthanide coordination polymers can be assembled using a combination of coordination and hydrogen bonds. Crystal data for 1a: monoclinic space group P2{sub 1}/c, a = 9.712(2) {angstrom}, b = 19.833(4) {angstrom}, c = 11.616(2) {angstrom}, {beta} = 111.89(3){degree}, Z = 4. Crystal data for 1f: monoclinic space group C2/c, a = 20.253(4) {angstrom}, b = 11.584(2) {angstrom}, c = 9.839(2) {angstrom}, {beta} = 115.64(3){degree}, Z = 8.

  15. Continuous parallel coordinates.

    PubMed

    Heinrich, Julian; Weiskopf, Daniel

    2009-01-01

    Typical scientific data is represented on a grid with appropriate interpolation or approximation schemes,defined on a continuous domain. The visualization of such data in parallel coordinates may reveal patterns latently contained in the data and thus can improve the understanding of multidimensional relations. In this paper, we adopt the concept of continuous scatterplots for the visualization of spatially continuous input data to derive a density model for parallel coordinates. Based on the point-line duality between scatterplots and parallel coordinates, we propose a mathematical model that maps density from a continuous scatterplot to parallel coordinates and present different algorithms for both numerical and analytical computation of the resulting density field. In addition, we show how the 2-D model can be used to successively construct continuous parallel coordinates with an arbitrary number of dimensions. Since continuous parallel coordinates interpolate data values within grid cells, a scalable and dense visualization is achieved, which will be demonstrated for typical multi-variate scientific data. PMID:19834230

  16. Magnetic Coordinate Systems

    NASA Astrophysics Data System (ADS)

    Laundal, K. M.; Richmond, A. D.

    2016-07-01

    Geospace phenomena such as the aurora, plasma motion, ionospheric currents and associated magnetic field disturbances are highly organized by Earth's main magnetic field. This is due to the fact that the charged particles that comprise space plasma can move almost freely along magnetic field lines, but not across them. For this reason it is sensible to present such phenomena relative to Earth's magnetic field. A large variety of magnetic coordinate systems exist, designed for different purposes and regions, ranging from the magnetopause to the ionosphere. In this paper we review the most common magnetic coordinate systems and describe how they are defined, where they are used, and how to convert between them. The definitions are presented based on the spherical harmonic expansion coefficients of the International Geomagnetic Reference Field (IGRF) and, in some of the coordinate systems, the position of the Sun which we show how to calculate from the time and date. The most detailed coordinate systems take the full IGRF into account and define magnetic latitude and longitude such that they are constant along field lines. These coordinate systems, which are useful at ionospheric altitudes, are non-orthogonal. We show how to handle vectors and vector calculus in such coordinates, and discuss how systematic errors may appear if this is not done correctly.

  17. Nutrition and the Aging Eye

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Vision Nutrition and the Aging Eye Past Issues / Winter ... related macular degeneration (AMD), the leading cause of vision loss for people over 60. But new research ...

  18. Childhood Eye Diseases and Conditions

    MedlinePlus

    ... and Conditions Nov. 01, 2013 The importance of vision screening There are many eye conditions and diseases ... child’s vision. Focus and alignment disorders that affect vision If any of the following conditions is suspected, ...

  19. Portable eye-safe ceilometers

    NASA Astrophysics Data System (ADS)

    Kryuchkov, A. V.; Grishin, A. I.; Gricuta, A. N.

    2014-11-01

    Developed and tested a simplified version of the definition of the cloud base height of the backscatter signal obtained in the laser meter height of the cloud base with eye-safe level of radiation intensity.

  20. Conjunctivitis (Pink Eye) in Newborns

    MedlinePlus

    ... Antibiotics Work Adenovirus Non-Polio Enterovirus Parent Portal Conjunctivitis (Pink Eye) in Newborns Language: English Español (Spanish) ... can be very serious. Symptoms and Causes of Conjunctivitis in Newborns Newborns with conjunctivitis develop drainage from ...