Global ETD Search

31	Hand-eye correlation an arbitrary sensorimotor contingency can alter visual sensitivity : a dissertation / Richters, David. January 1900 (has links) Thesis (Ph. D)--Northeastern University, 2008. / Title from title page (viewed March 25, 2009). Graduate School of Arts and Sciences, Dept. of Psychology. Includes bibliographical references (p. 154-161).
32	The effects of perceptual, motor and cognitive constraints on obstacle avoidance during reaching Ross, Alasdair Iain January 2016 (has links) Performing goal-directed hand-movements in the presence of obstacles is a task that we usually complete successfully many times a day without much conscious consideration. Yet, little is known about the underlying processes. The aim of this thesis was to investigate the role of perceptual, motor and cognitive constraints on obstacle avoidance during reaching. To do this a tabletop-based obstacle avoidance setup and motiontracking were used. In the first experimental chapter, the previously reported tendency of participants to select movement paths that pass roughly through the mid-point between two obstacles was examined. The starting position of the hand and the availability of visual feedback were manipulated and evidence was found that movement path selection depends on both a collision-avoidance strategy and the associated biomechanical costs; even when visual feedback is unavailable. The second experimental chapter investigated an action-blindsight phenomenon, specifically the ability of cortically blind patients to avoid unseen obstacles. It was found that only two out of the six patients tested potentially showed some residual sensitivity to obstacles in their blind visual field. The final two experimental chapters went further to examine the role of perceptual information and attentional mechanisms respectively. It was found that during obstacle avoidance participants predominantly look at the movement target and rarely towards any obstacles or their moving hand. Furthermore, they tend to move their hand away from obstacles that are fixated. Finally, it was also found that a concurrent attentional task affected movement path selection in a similar way. At present it is unclear whether these perceptual and attentional effects are additive or independent of each other. Overall, these findings suggest that both conscious visual information and attentional mechanisms are crucial factors in determining movement path selection during obstacle avoidance in reaching. 153
33	Immersive Eye Tracking Calibration in Virtual Reality Using Interactions with In-game Objects / IMMERSIV ÖGONSPÅRNINGSKALIBRERING I VIRTUELL VERKLIGHET MED HJÄLP AV INTERAKTIONER MED IN-GAME OBJEKT Sidenmark, Ludwig January 2017 (has links) This thesis aims to investigate an eye tracking calibration method in virtual reality where users’ visual attention from eye-hand coordination is used when interacting with in-game items. This could potentially allow eye tracking calibration without interrupting the virtual experience, in comparison with traditional eye tracking calibration which is cumbersome, disruptive, and requires the user’s full attention. A user study was conducted with 15 participants in which they were tasked to complete three different interactions. The interactions tested were a knob, a slider and a liftable cube. Where in the virtual environment the participants were looking during the interactions was recorded and processed to enable comparison. The processed data was analysed to find factors that influenced the calibration method. Additionally, the results was analysed to find at what point during the interactions that has the most consistent eye tracking fixations on the interacted item, and therefore most potential for eye tracking calibration. The results showed that when the participant is interacting with the item and the interacted item is stationary, we received a fixation for around 60% of all trials at any time. When the interacted item was moving the results indicated a lower percentage. To increase this number, the gaze data should be filtered instead of using raw gaze data in order to avoid flickering from the eye tracker. Regarding factors that influence the calibration method, the choice of interaction has a big impact on the method’s success where interactions in which the interacted item is stationary has more potential. Additionally, interactions that take longer time and requires precision in order to complete the interaction positively influences the potential of the calibration method. The surrounding virtual environment also has an influence, as a more distracting environment can negatively impact the calibration method. / Denna avhandling ämnar att att undersöka en kalibreringsmetod för ögonspårning i virtuell verklighet där användarnas visuella uppmärksamhet från ögon och hand koordination används när man interagerar med objekt i den virtuella verkligheten. Detta kan möjliggöra kalibrering av ögonspårning utan att avbryta den virtuella upplevelsen, i jämförelse med traditionell kalibrering som är besvärlig, störande och kräver användarens fulla uppmärksamhet. En användarstudie genomfördes med 15 deltagare där de hade till uppgift att slutföra tre olika interaktioner. De testade interaktionerna var en knopp, en slider och en lyftbar kub. Deltagarnas blick spelades in under interaktionerna och analyserades för att möjliggöra jämförelse. Den bearbetade data analyserades för att hitta faktorer som påverkar kalibreringsmetoden. Dessutom analyserades resultaten för att hitta vid vilken tidpunkt under interaktionerna som hade de mest konsekventa ögonfixeringarna på objektet de interagerade med och därmed störst potential för kalibrering av ögonspårning. Resultaten visade att när deltagaren interagerar med objektet och det interaktiva objektet är stillastående, fick vi en fixering för omkring 60% av alla försök under godtycklig tidpunkt. När det interaktiva objektet rörde sig, visade resultaten en lägre procentandel. För att öka antalet, ska blickdatan filtreras i stället för att använda rå blickdata för att undvika att flicker från ögonspåraren. När det gäller faktorer som påverkar kalibreringsmetoden har valet av interaktion stor inverkan på metodens framgång, där interaktioner där det interaktiva objektet är stationärt har större potential. Dessutom påverkar interaktioner som tar längre tid och kräver precision för att slutföra interaktionen kalibreringsmetodens potential positivt. Den omgivande virtuella miljön har också inflytande, eftersom en mer distraherande miljö kan negativt påverka kalibreringsmetoden. Virtual Reality Eye Tracking Eye-hand Coordination Calibration Human Computer Interaction
34	Etude des mécanismes prédictifs sous-jacents à la coordination œil-main / Investigating predictive mechanisms underlying eye-hand coordination Mathew, James 12 September 2018 (has links) La capacité de coordonner efficacement nos yeux avec nos mains est déterminante pour le succès de nos actions quotidiennes. En outre la capacité de prédire les conséquences sensorielles de nos propres actions est cruciale pour nos habilités motrices. Dans ce travail, à l’aide d’une tâche dans laquelle les participants doivent suivre avec leurs yeux une cible visuelle bougée par leur main, nous nous intéressons aux mécanismes prédictifs sous-tendant la coordination œil-main. Dans une première étude utilisant un protocole d’adaptation à une rotation visuomotrice, nous montrons que ces mécanismes prédictifs peuvent être mis à jour indépendamment de notre capacité à effectuer des mouvements précis de la main. Dans l’étude suivante nous cherchons à déterminer l’effet de la préférence manuelle, et montrons que malgré des différences évidentes en termes de précision concernant le contrôle manuel, la capacité d’anticiper les conséquences visuelles de nos actions reste identique que la cible soit bougée par la main droite ou gauche. Enfin, grâce à la stimulation magnétique transcranienne, nous testons l'hypothèse selon laquelle ces mécanismes prédictifs utilisent des signaux efférents de la main issus du cortex moteur primaire (M1). Nos résultats montrent que si cette contribution existe, elle doit se faire nécessairement en amont de M1. Au bout du compte nous proposons que la coordination œil-main soit sous-tendue par des mécanismes prédictifs similaires pour nos deux mains, situés vraisemblablement en amont de M1, et pouvant être mis à jour indépendamment du contrôle de la main. / The ability to coordinate efficiently eye and hand actions is central for humans in everyday activities. Furthermore it is argued that the ability to predict the sensory consequences of self-initiated movements is crucial for skilled motor behavior. Here by means of a task in which participants were asked to track with the eyes a visual target that was moved by their hand, we investigated the predictive mechanisms underlying eye-hand coordination. In a first study, using a protocol in which participants had to adapt to rotated hand visual feedback, we show that these predictive mechanisms can be updated independently of the ability to perform accurate hand movements. In a follow up study we tested the effect of hand dominance, and showed that, despite obvious differences in the accuracy of hand movement control, the ability to predict visual consequences of right and left hand actions was similar. Finally, by means of transcranial magnetic stimulation, we tested the hypothesis that those predictive mechanisms rely on hand efferent signals from the primary motor cortex (M1). However our results failed to support this view, and instead suggest that if such a contribution exists, it must be upstream of M1. Overall, we propose that eye-hand coordination relies on similar predictive mechanisms for both hands, possibly located upstream of M1, which can be updated independently of hand movement control. Coordination œil-Main Mouvements oculaires Stimulation magnétique transcrânienne Adaptation visuomotrice Contrôle moteur Prédiction Eye-Hand coordination Motor control Prediction Eye movements Transcranial magnetic stimulation Visuomotor adaptation
35	Rankos ir žiūros taško judesių koordinacija panaudojant labirinto testą / Coordination of eye-hand movements using labyrinth path Kulvelis, Saulius 04 August 2011 (has links) Žmogaus natūralus elgesys puikiai parodo sinchronizuotus akių ir rankos judesius. Akių-rankos koordinacija naudinga tiriant alternatyvius kompensacinius įtaisus, kurie gelbsti žmogaus ir kompiuterio sąveikai, kai reabilituojami žmonės su negale. Tiriamieji buvo paprašyti pravesti ranka kursorių labirinto trajektorija (pakankamai dideliu greičiu). Eksperimento metu akių judesiai buvo fiksuojami "EyeGaze" sistema sukurta "LC technologies LTd.". Rezultatuose nustatytos akių-rankos judesių koordinacijos strategijos: GJ - šuolinė ir GMS - sekimo strategija. / Human behavior in manual control coordinated by vision illustrates perfect synchronization between the gaze and position of the target, which is controlled by hand. Investigation of eye-hand coordination is useful for alternative control of computer cursor and for an assessment and rehabilitation of a sensorimotor system of patients. Subjects were asked to move the target along the labyrinth’s path quickly enough. During all experiments, movements of both eyes were recorded with eye tracker “EyeGaze System” produced by “LC Technologies Ltd.” Gaze tracking instrumentation was setup so, that to 1 deg eye angle corresponds to 46 pixels on computer screen. The results showed two eye-hand coordination strategies Gaze Jumps (GJ) and Gaze Moves Smoothly (GMS) during guiding self-moved target along Labyrinth path can be defined. During GJ strategy gaze elicit eye jumps in the direction of the future path. Average amplitude of the jumps is around 1.5 deg and frequency is in the 2-3 Hz range. During GMS strategy gaze is concentrated on the self-moved target and leads it only by small average distance (0.1-0.2 deg). Electronics and Electrical Engineering Rankos ir akių koordinacija Akies šuoliai Sakados Eye-hand coordination Eyegaze Gj and gms strategy Sacades
36	Evaluering van die Vienna toetsbattery in die voorspelling van effektiewe busbestuurder gedrag Du Toit, Martina Petronella 30 November 2006 (has links) Vehicle accidents by means of Public transport annually leads to a large number of passenger deaths and life long disablement. AsDu Toit, Martina Petronella a result, there is a need for preventative measures by identifying the psychomotor abilities of bus drivers during the recruitment and selection process of employment. The study was conducted among 398 bus drivers employed by a large bus company. The Vienna Test Battery was administered. It was found that distance estimation, ability to recognize forms and figures, concentration ability, eye-hand feet coordination and two-hand coordination predicted the effectiveness of bus drivers successfully. It is suggested that further research should focus on client services, attitude of bus drivers and learning potential, as factors that influence the effectiveness of bus drivers. / Industrial psychology / M.A. (Industrial Psychology) Bus driver Human abilities Prediction Vienna test battery Bus driver behaviour Psychomotor ability Accidents Distance estimation Two hand coordination Concentration ability Eye-hand-feet coordination Text in Afrikaans 150.287 Vienna Test System Bus drivers -- Ability testing Motor ability Eye-hand coordination Attention Traffic accidents Bus accidents
37	Evaluering van die Vienna toetsbattery in die voorspelling van effektiewe busbestuurder gedrag Du Toit, Martina Petronella 30 November 2006 (has links) Vehicle accidents by means of Public transport annually leads to a large number of passenger deaths and life long disablement. AsDu Toit, Martina Petronella a result, there is a need for preventative measures by identifying the psychomotor abilities of bus drivers during the recruitment and selection process of employment. The study was conducted among 398 bus drivers employed by a large bus company. The Vienna Test Battery was administered. It was found that distance estimation, ability to recognize forms and figures, concentration ability, eye-hand feet coordination and two-hand coordination predicted the effectiveness of bus drivers successfully. It is suggested that further research should focus on client services, attitude of bus drivers and learning potential, as factors that influence the effectiveness of bus drivers. / Industrial psychology / M.A. (Industrial Psychology) Bus driver Human abilities Prediction Vienna test battery Bus driver behaviour Psychomotor ability Accidents Distance estimation Two hand coordination Concentration ability Eye-hand-feet coordination Text in Afrikaans 150.287 Vienna Test System Bus drivers -- Ability testing Motor ability Eye-hand coordination Attention Traffic accidents Bus accidents
38	The relationship between touch sensation of the hand and occupational performance in individuals with chronic stroke Hill, Valerie A. 11 July 2014 (has links) Indiana University-Purdue University Indianapolis (IUPUI) / Stroke is the main cause of disability in the United States. Individuals with stroke commonly report sensory impairment affects their recovery. Motor recovery and sensory impairment are related and impact individuals’ ability to perform valued occupations. Despite the prevalence of sensation impairment after stroke, many occupational therapists fail to include sensation assessment and intervention in treatment planning. The exclusion of sensation in occupational therapy interventions during stroke rehabilitation may be due to the lack of literature supporting the association between sensation and occupational performance. The current study aimed to determine the relationship between touch sensation of the affected hand and occupational performance and satisfaction in individuals with chronic stroke. Using a cross-sectional study design, this study associated factors related to hand sensation and function in individuals with chronic stroke. Fifty individuals with chronic stroke participated in a one-time testing session in which assessments related to sensation, movement of the hand and engagement in daily activities were administered. Correlation analyses were utilized to determine relationships between touch sensation of the affected hand with individuals’ abilities to engage in valued daily activities, arm and hand disability, and manual abilities. The main finding of the study was that individuals with intact sensation reported greater ability to perform valued occupations and satisfaction with their performance, as compared with individuals with touch sensation impairment. For individuals with impaired touch sensation of the affected hand, impairment of touch sensation of the hand did not correlate with individuals’ performance or satisfaction with valued occupations, arm or hand movement, or manual abilities. Collectively, the results of this study reflect the complex interaction between touch sensation, occupational performance, motor functioning, and manual abilities of the affected hand for individuals’ who have experienced a stroke. This study informs therapists, rehabilitation scientists, and other healthcare professionals that client-centered, individualized approaches, including a wide array of clinical assessments and intervention, including assessment of occupational performance and sensation, remain important components in stroke rehabilitation. Cerebrovascular disease -- United States Cerebrovascular disease -- Treatment Touch -- Therapeutic use Hand -- Measurement Motor ability -- Testing Outcome assessment (Medical care) Therapist and patient Eye-hand coordination -- Testing Senses and sensation -- Testing Occupational therapy -- Ability testing Chronic diseases -- Research Chronically ill -- Rehabilitation Quality of life Movement therapy
39	Varför Ava-tar de på allt? : En kvalitativ analys av hur visualiseringen av händers interaktion påverkar hur åskådare upplever världen i filmen Avatar / Ava-Targeting Hands? : A Qualitative Analysis of How the Visualisation of Hand Interaction Affects the Viewers’ Perceptions of the World in the Movie Avatar Campbell, Cassandra January 2023 (has links) Denna uppsats är en fenomenologisk studie som utreder hur visualiseringen av händer påverkar hur filmbetraktare upplever världen i filmen Avatar. Analysen utreder tre scener från Avatar, som visar händer som interagerar med föremål som är okända för både filmkaraktärens och betraktarens del. Undersökningen applicerar teorier inom fenomenologi, perception, kognitionsteorier, och science fiction som narrativ form, i syfte att utreda hur människor påverkas av att betrakta händers interaktion i ett filmsammanhang. Resultatet i analysen landar i att visualiseringen av händers interaktion kan ha flera olika effekter för hur filmåskådaren upplever scenerna som har utretts. Interaktionerna har bland annat en narrativ funktion då de förmedlar information om hur den fiktiva filmvärlden är uppbyggd, vilket i sin tur fångar åskådarens intresse och skapar spänning. Vidare styrker fenomenologiska teorier att interaktionerna kan trigga sensoriska upplevelser hos betraktaren i form av exempelvis taktila förnimmelser. Analysen landar även i att åskådare kan triggas till att vilja interagera med filmmiljön på egen hand, eftersom teorier inom kognition styrker att händers närvaro gör att vi tolkar omgivningen som interaktiv. Samtidigt påvisar även resultatet att upplevelser är svåra att mäta, och att våra tolkningar skiljer sig åt eftersom de formas av våra tidigare erfarenheter och intressen. Analysen avslutas med en kritisk reflektion kring resultatet och öppnar sedan upp för hur ovannämnda aspekter kan bana väg för forskning inom filmberättande, medicin, interaktionsdesign, UX-design, och visuell kommunikation, samt hur analysen i uppsatsen hade kunnat breddas till en större studie. Denna uppsats inkluderar även en designdokumentation efter sida 44 vid namn ”Arg på vargen?”, som är en del av examensarbetet som denna uppsats ingick i vid programmet Visuell kommunikation på Malmö Universitet. ”Arg på vargen?” är en animerad teater som belyser varför vargar behövs i den svenska naturen. / This essay is a phenomenological study that explores how the visualisation of hands affects the viewer’s perception of the world in the movie Avatar. The essay analyses three scenes from Avatar, consisting of hands that interact with objects that are unknown to both the movie character and the viewer. The analysis applies theories within phenomenology, perception, cognition, and science fiction as a narrative form, as it aims to explore how viewers perceive the interaction of hands in the context of watching a movie. The results suggest that the visualisation of hands can have several outcomes, regarding how the viewer reacts while watching the scenes that were involved in this study. The interactions serve a narrative function, as they convey information about the construction of the fictional film world. This in turn, engages the viewer’s interest and creates anticipation. Theories within phenomenology support that viewers can experience sensory perceptions, such as tactile sensations, while watching the scenes. The analysis also concludes that viewers may wish to interact with the film world by using their own hands, as cognition theories support that the presence of hands in our field of vision, prompts us to interpret our surroundings as being interactive. The findings in this study also conclude that experiences are difficult to measure and interpret, since our perceptions are shaped by our previous experiences and interests. The essay closes with a critical reflection on the results and elaborates on how the findings can be applied to different research fields, such as film narration, medicine, interaction design, UX design, and visual communication, followed by how the analysis in this essay could be expanded into a larger study. Avatar phenomenology film phenomenology perception hands cognition narrative narrative functions embodiment embody immersion science fiction interaction tactile haptic sensory eye-hand-coordination visual communication communication film Avatar fenomenologi filmfenomenologi perception händer hand kognition narrativ narrativa funktioner inlevelse förkroppsligande science fiction interaktion interaktionsdesign taktil haptik öga-hand-koordination sensorisk upplevelse visuell kommunikation kommunikation film filmberättande vargar varg teater Naturskyddsföreningen animation rörlig bild naturpolitik narrativ berättande kommunikation visuell kommunikation Cultural Studies Kulturstudier Philosophy Filosofi Studies on Film Filmvetenskap Human Computer Interaction Interaction Technologies Interaktionsteknik

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