Impairment of stereoacuity is common in the elderly population and is found to be a risk factor for falls. The purpose of these experiments was to extend knowledge regarding impairment of binocular vision and adaptive gait. Firstly using a 3D motion analysis system to measure how impairment of stereopsis affected adaptive gait during a negotiation of a step, secondly by determining which clinical stereotest was the most reliable for measuring stereoacuity in elderly subjects and finally investigating how manipulating the perceived height of a step in both binocular and monocular conditions affected negotiation of a step. In conditions of impaired stereopsis induced by acutely presented monocular blur, both young and elderly subjects adopted a safety strategy of increasing toe clearance of the step edge, even at low levels of monocular blur (+0.50DS) and the effect was greater when the dominant eye was blurred. The same adaptation was not found for individuals with chronic monocular blur, where vertical toe clearance did not change but variability of toe clearance increased compared to full binocular correction. Findings indicate stereopsis is important for accurately judging the height of a step, and offers support to epidemiological findings that impaired stereoacuity is a risk for falls. Poor agreement was found between clinical stereotests. The Frisby test was found to have the best repeatability. Finally, a visual illusion that caused a step to be perceived as taller led to increased toe elevation. This demonstrates a potential way of increasing toe clearance when stepping up and hence increase safety on stairs. / The Study data files are unavailable online.

Impairment of stereoacuity is common in the elderly population and is found to be a risk factor for falls. The purpose of these experiments was to extend knowledge regarding impairment of binocular vision and adaptive gait. Firstly using a 3D motion analysis system to measure how impairment of stereopsis affected adaptive gait during a negotiation of a step, secondly by determining which clinical stereotest was the most reliable for measuring stereoacuity in elderly subjects and finally investigating how manipulating the perceived height of a step in both binocular and monocular conditions affected negotiation of a step. In conditions of impaired stereopsis induced by acutely presented monocular blur, both young and elderly subjects adopted a safety strategy of increasing toe clearance of the step edge, even at low levels of monocular blur (+0.50DS) and the effect was greater when the dominant eye was blurred. The same adaptation was not found for individuals with chronic monocular blur, where vertical toe clearance did not change but variability of toe clearance increased compared to full binocular correction. Findings indicate stereopsis is important for accurately judging the height of a step, and offers support to epidemiological findings that impaired stereoacuity is a risk for falls. Poor agreement was found between clinical stereotests. The Frisby test was found to have the best repeatability. Finally, a visual illusion that caused a step to be perceived as taller led to increased toe elevation. This demonstrates a potential way of increasing toe clearance when stepping up and hence increase safety on stairs.

Les buts des recherches présentées dans cette thèse étaient d’évaluer le rôle de la stéréoscopie dans la reconnaissance de forme, dans la perception du relief et dans la constance de forme. La première étude a examiné le rôle de la stéréoscopie dans la perception des formes visuelles en utilisant une tâche de reconnaissance de formes. Les stimuli pouvaient être présentés en 2D, avec disparité normale (3D) ou avec disparité inversée. La performance de reconnaissance était meilleure avec les modes de présentation 2D et 3D qu’avec la 3D inversée. Cela indique que la stéréoscopie contribue à la reconnaissance de forme. La deuxième étude s’est intéressée à la contribution conjointe de l’ombrage et de la stéréoscopie dans la perception du relief des formes. Les stimuli étaient des images d’une forme 3D convexe synthétique présentée sous un point de vue menant à une ambigüité quant à sa convexité. L’illumination pouvait provenir du haut ou du bas et de la gauche ou de la droite, et les stimuli étaient présentés dichoptiquement avec soit de la disparité binoculaire normale, de la disparité inversée ou sans disparité entre les vues. Les participants ont répondu que les formes étaient convexes plus souvent lorsque la lumière provenait du haut que du bas, plus souvent avec la disparité normale qu’en 2D, et plus souvent avec absence de disparité qu’avec disparité inversée. Les effets de direction d’illumination et du mode de présentation étaient additifs, c’est-à-dire qu’ils n’interagissaient pas. Cela indique que l’ombrage et la stéréoscopie contribuent indépendamment à la perception du relief des formes. La troisième étude a évalué la contribution de la stéréoscopie à la constance de forme, et son interaction avec l’expertise perceptuelle. Elle a utilisé trois tâches de discrimination séquentielle de trombones tordus ayant subi des rotations en profondeur. Les stimuli pouvaient être présentés sans stéréoscopie, avec stéréoscopie normale ou avec stéréoscopie inversée. Dans la première moitié de l’Exp. 1, dans laquelle les variations du mode de présentation étaient intra-sujets, les performances étaient meilleures en 3D qu’en 2D et qu’en 3D inversée. Ces effets ont été renversés dans la seconde moitié de l’expérience, et les coûts de rotation sont devenus plus faibles pour la 2D et la 3D inversée que pour la 3D. Dans les Exps. 2 (variations intra-sujets du mode de présentation, avec un changement de stimuli au milieu de l’expérience) et 3 (variations inter-sujets du mode de présentation), les effets de rotation étaient en tout temps plus faibles avec stéréoscopie qu’avec stéréoscopie inversée et qu’en 2D, et plus faibles avec stéréoscopie inversée que sans stéréoscopie. Ces résultats indiquent que la stéréoscopie contribue à la constance de forme. Toutefois, cela demande qu’elle soit valide avec un niveau minimal de consistance, sinon elle devient stratégiquement ignorée. En bref, les trois études présentées dans cette thèse ont permis de montrer que la stéréoscopie contribue à la reconnaissance de forme, à la perception du relief et à la constance de forme. De plus, l’ombrage et la stéréoscopie sont intégrés linéairement. / The goals of the researches presented in this thesis were to evaluate the role of stereopsis in shape recognition, in relief perception, and in shape constancy. The first study examined the role of stereopsis in visual shape perception using a recognition task. The stimuli were presented with null binocular disparity (i.e. 2D), normal binocular disparity (3D) or reversed disparity. Recognition performance was better with 2D and 3D displays than with reversed 3D. This indicates that stereopsis contributes to shape recognition. The second study examined the joint contribution of shading and stereopsis to the relief perception of shape. The stimuli were the images of a synthetic convex 3D shape seen from viewpoints leading to ambiguity as to its convexity. Illumination either came from above, or below and from the right or the left, and stimuli were presented dichoptically with either normal binocular disparity, reversed disparity, or no disparity between the views presented at each eye. Participants responded “convex” more often when the lighting came from above than from below. Also, participants responded that the shape was convex more often with normal than with zero disparity, and more often with 2D than with reversed stereopsis. The effects of lighting direction and display mode were additive; i.e. they did not interact. This indicates that shading and stereopsis contribute independently to shape perception. The third study assessed the contribution of stereopsis to shape constancy and how it interacts with perceptual expertise using three sequential matching tasks with bent paperclips rotated in depth. Stimuli were presented without stereopsis, or with normal or reversed stereopsis. In the first half of Exp. 1, where display mode variations were within-subject, the performances were better with stereoscopic displays than with 2D or reversed stereoscopic presentations. In the second half of the experiment, the rotation costs became weaker for the 2D and reversed 3D display modes than for the 3D one. In Exps. 2 (display mode within-subject, with stimuli switched halfway into the experiment) and 3, (display mode between-subjects) the rotation effect was consistently weaker with normal stereo than with either 2D or reversed stereoscopic displays. These experiments also demonstrate an advantage of reversed stereo over 2D presentations. This indicates that stereo may contribute to shape constancy. This, however, requires stereoscopic information to be valid with a minimal degree of consistency. Otherwise, stereo may become strategically ignored. In a nutshell, the three studies presented in this thesis showed that stereo contributes to shape recognition, relief perception and shape constancy. Furthermore stereopsis and shading are integrated independently.

Yes / Purpose: Two binocular sources of information serve motion-in-depth (MID) perception: changes in disparity over time (CD), and interocular velocity differences (IOVD). While CD requires the computation of small spatial disparities, IOVD could be computed from a much lower-resolution signal. IOVD signals therefore might still be available under conditions of binocular vision impairment (BVI) with limited or no stereopsis, e.g. amblyopia. Methods: Sensitivity to CD and IOVD was measured in adults who had undergone therapy to correct optical misalignment or amblyopia in childhood (n=16), as well as normal vision controls with good stereoacuity (n=8). Observers discriminated the interval containing a smoothly-oscillating MID “test” stimulus from a “control” stimulus in a two-interval forced choice (2IFC) paradigm. Results: Of the BVI observers with no static stereoacuity (n=9), one displayed evidence for sensitivity to IOVD only, while there was otherwise no sensitivity for either CD or IOVD in the group. Generally, BVI observers with measurable stereoacuity (n=7) displayed a pattern resembling the control group: showing a similar sensitivity for both cues. A neutral-density (ND) filter placed in front of the fixing eye in a subset of BVI observers did not improve performance. Conclusions: In one BVI observer there was preserved sensitivity to IOVD but not CD, though overall only those BVI observers with at least gross stereopsis were able to detect disparity-based or velocity-based cues to MID. The results imply that these logically distinct information sources are somehow coupled, and in some cases BVI observers with no stereopsis may still retain sensitivity to IOVD. / UK Biotechnology and Biological 498 Sciences Research Council (BBSRC): BB/M002543/1 (Alex R. Wade) BB/M001660/1 (Julie 499 M. Harris) and BB/M001210/1 (Marina Bloj)

OBJETIVOS: Comparar a aniseiconia e a estereopsia em escolares anisometropes do primeiro ano do ensino fundamental corrigidos com lentes oftálmicas de estoque com curvas-base selecionadas para minimizar a diferença de tamanho interocular das imagens retínicas e com lentes iseicônicas sugeridas pelo software Aniseikonia Inspector 3 e verificar a preferência dos escolares por uma destas formas de correção. MÉTODOS: Dezenove escolares com anisometropia >= 1,5 D em meridianos correspondentes no uso de óculos com lentes oftálmicas de estoque e com lentes iseicônicas foram avaliados para aniseiconia (software niseikonia Inspector 3) e estereopsia (teste Stereo Fly test com símbolos LEA. A preferência por uma das formas de correção foi verificada após 40-50 dias de uso dos óculos. RESULTADOS: As médias e os desvios-padrão das aniseiconias vertical e horizontal no uso de óculos com lentes oftálmicas de estoque e com lentes iseicônicas foram, respectivamente, -1,05% ± 2,20% e -1,37% ± 2,36% (p=0,82739) e -0,895% ± 2,23% e -1,16% ± 2,03% (p=0,77018). Os optotipos que sugerem estereopsia < 100 segundos de arco foram identificados por por 31,6% dos escolares corrigidos com lentes iseicônicas e por 21,1% dos escolares corrigidos com lentes oftálmicas de estoque (p= 0,475). Em relação à preferência, 4/15 (26,7%) escolheram os óculos com lentes iseicônicas, 2/15 (13,3%) escolheram os óculos com lentes oftálmicas de estoque e para 9/15 (60%) a escolha foi indiferente. CONCLUSÃO: A aniseiconia induzida nos escolares anisometropes corrigidos com lentes iseicônicas sugeridas pelo software Aniseikonia Inspector 3 foi similar à obtida na correção com lentes oftálmicas de estoque com curvas-base selecionadas para minimizar a diferença de tamanho interocular das imagens retínicas / OBJECTIVES: To compare the aniseikonia and the stereopsis in children of the first-year of elementary school with anisometropia corrected with stock ophthalmic lenses with base curve selected to minimize the interocular size difference of retinal images and with size lenses suggested by the software Aniseikonia Inspector 3, and to check the preference of them for one of these forms of correction. METHODS: Nineteen school children with anisometropia >= 1.5 D in corresponding meridians, in the use of glasses with stock ophthalmic lenses and with size lenses were evaluated for aniseikonia (software Aniseikonia Inspector 3) and stereopsis (Stereo Fly test with LEA symbols). The preference for one of the forms of correction was verified after 40-50 days of wearing glasses. RESULTS: The mean and standard deviations of the vertical and horizontal aniseikonia in the use of glasses with stock ophthalmic lenses and with size lenses were, respectively,-1.05% ± 2.20% and -1.37% ± 2.36% (p = 0,82739) and -0.895% ± 2.23% and -1.16% ± 2.03% (p = 0,77018). 31.6% of the school children corrected with size lenses and 21.1% of the students corrected with stock ophthalmic lenses identified the optotypes that suggest stereopsis less than 100 seconds of arc (p = 0.475). Regarding the preference, 4/15 (26.7%) of the students chose the glasses with size lenses, 2/15 (13.3%) chose the glasses with stock ophthalmic lenses, and for 9/15 (60%) the choice was indifferent. CONCLUSION: The induced aniseikonia in school children with anisometropia corrected with size lenses suggested by the software Aniseikonia Inspector 3 was similar to that obtained in the correction with stock ophthalmic lenses with base curves selected to minimize the difference of interocular size of retinalimages

[pt] As comunicações à distância estão crescendo consideravelmente pelo uso de aplicações através da Internet e de ambientes virtuais. Interaçõoes sociais e pessoais têm recebido especial enfoque, sobretudo a videoconferência, acarretando uma grande demanda de tecnologia apropriada para esses sistemas. Resultados de pesquisas em Presença, alguns deles obtidos nesta tese, permitiram inferir os quatro pilares da proposta: 1. visualização é muito importante nas interações sociais/pessoais; 2. tecnologia simples pode promover presença social; 3. imagens de câmera são mais satisfatórias do que avatares para algumas interações sociais/pessoais; 4. estereoscopia influência presença positivamente. Sob a restrição de usar tecnologia simples e de baixo custo, a tese propõe o uso de visualização estereoscópica para webcams, em tempo real. Porque webcams são equipamentos simples com baixa resolução de imagem, a obtenção de um estéreo com qualidade torna- se um desafio. Partindo do princípio que o olho humano não se comporta da mesma forma para ver de perto e de longe, a pesquisa analisou o processamento de estéreo natural do olho humano, e com base em resultados psicofísicos e fisiológicos da visão binocular, a tese propõe um modelo para o processamento de imagens estereoscópicas a serem visualizadas em curta distância, e usa este modelo na implementação apresentada. Os resultados obtidos foram satisfatórios para a visualização de imagens estéreo com webcams, em tempo real, e principalmente, eliminaram a necessidade de reajuste de paralaxe das imagens e do reposicionamento das câmeras a cada movimentação do observador, dando assim mais liberdade de visualização ao observador. / [en] The improvement of communication among remotely located people constitutes a very comprehensive prominent subject nowadays. Among applications to attain this goal, some aim to support social and personal interactions to meet partners, friends and family in distance. Presence research results, some obtained as part of this thesis, allowed to infer the four pillars of the proposal: 1. visualization is very important in social/personal interactions, mainly when people have close social/personal relationship; 2. simple technology can afford social presence; 3. camera images are more satisfactory than avatars during some social/personal interactions; 4. stereoscopy influences presence positively. Under the constraint of using simple technology without adding any special hardware to a PC system, the thesis proposes the use of stereoscopy through webcams, in real- time, as one solution to add 3D features to camera images. Since webcams are simple equipments with low resolution, to obtain stereo images in good quality is a challenge. Considering the fact that human eyes treat short and long distance in a different way, this research analysed the natural stereo processing of human eye, and based on psychophysical and physiological features of binocular vision, the thesis proposes a model to process stereoscopic images to be visualized in short distance, and implemented it as a proof of concept. The obtained results are satisfactory for stereoscopic images visualization through webcams, in real-time, and mainly, eliminated the need of adjusting images parallax and cameras position for each viewer´s movement, allowing more freedom to the viewer.

Of all motor skills, manual reaching might be the one ability that matters most for infants’ perceptual, cognitive and social development. Reaching allows infants to learn about object properties, but also gives opportunities for socializing with others. The general aim of the present thesis was to study the importance of manual motor development in infancy from different perspectives; first, through examining stereopsis as a prerequisite for efficient reaching development, second, with regard to understanding others goal-directed reach actions by means of the mirror neuron system (MNS), and third, in relation to possible atypical development, with a specific focus on autism spectrum disorder (ASD). Study I shows that under monocular viewing conditions, infants at six, eight and 10 months of age perform slower and less accurate reaches. Longer times to object contact during monocular trials specifically imply that motor prediction is less effective when depth and distance information is compromised. Study II demonstrates that, by eight months of age, infants seem to have a MNS that functions in a similar manner to the adult MNS, thus activity can be registered over the motor cortex when infants simply observe an action they can master themselves. This activation is predictive, indicating anticipation of the goal of the observed reach. Study III indicates that infants at elevated familial risk for ASD present with reduced prospective motor control at 10 months of age. Compared to a low-risk control sample, high-risk infants perform reactive rather than predictive reach actions. Follow-up assessment at 36 months will show whether this measure can be used as a predictive diagnostic marker for ASD. The main contribution given by this work is the insight that it is important to take manual motor aspects into account when considering typical as well as atypical cognitive and social development, and in addition, that motor prediction is a key factor behind being able to timely execute and understand reaching actions.

No description available.

La evolución de la tecnología de Realidad Virtual (RV) ha contribuido en todos los campos, incluyendo la psicología. Esta evolución implica mejoras tanto en hardware como en software, que permiten experiencias más inmersivas. En un entorno de RV los usuarios pueden percibir la sensación de "presencia" y sentirse "inmersos". Estas sensaciones son posibles utilizando HMDs. Hoy en día, el desarrollo de los HMDs se ha centrado en mejorar sus características técnicas para ofrecer inmersión total. En psicología, los entornos de RV son una herramienta de investigación. Hay algunas aplicaciones para evaluar la memoria espacial que utilizan métodos básicos de interacción. Sin embargo, sistemas de RV que incorporen estereoscopía y movimiento físico todavía no se han explotado en psicología. En esta tesis, se ha desarrollado un nuevo sistema de RV que combina características inmersivas, interactivas y de movimiento. El sistema de RV (tarea en un laberinto virtual) se ha utilizado para evaluar la memoria espacial y la percepción de profundidad. Se han integrado dos tipos diferentes de interacción: una basada en locomoción que consistió en pedalear en una bicicleta fija (condición1) y otra estacionaria usando un gamepad (condición2). El sistema integró dos tipos de visualización: 1) Oculus Rift (OR); 2) Una gran pantalla estéreo. Se diseñaron dos estudios. El primer estudio (N=89) evaluó la memoria espacial a corto plazo usando el OR y los dos tipos de interacción. Los resultados indican que existían diferencias significativas entre ambas condiciones. Los participantes que utilizaron la condición2 obtuvieron mejor rendimiento que los que utilizaron la tarea en la condición1. Sin embargo, no se encontraron diferencias significativas en las puntuaciones de satisfacción e interacción entre ambas condiciones. El desempeño en la tarea correlacionó con el desempeño en las pruebas neuropsicológicas clásicas, revelando la verosimilitud entre ellas. El segundo estudio (N=59) incluyó participantes con y sin estereopsis. Este estudio evaluó la percepción de profundidad comparando los dos sistemas de visualización. Los participantes realizaron la tarea usando la condición2. Los resultados mostraron que las diferentes características del sistema de visualización no influyeron en el rendimiento en la tarea entre los participantes con y sin estereopsis. Se encontraron diferencias significativas a favor del HMD entre las dos condiciones y entre los dos grupos de participantes respecto a la percepción de profundidad. Los participantes que no tenían estereopsis y no podían percibir la profundidad cuando utilizaban otros sistemas de visualización, tuvieron la ilusión de percepción de profundidad cuando utilizaron el OR. El estudio sugiere que para las personas que no tienen estereopsis, el seguimiento de la cabeza influye en gran medida en la experiencia 3D. Los resultados estadísticos de ambos estudios han demostrado que el sistema de RV desarrollado es una herramienta apropiada para evaluar la memoria espacial a corto plazo y la percepción de profundidad. Por lo tanto, los sistemas de RV que combinan inmersión total, interacción y movimiento pueden ser una herramienta útil para la evaluación de procesos cognitivos humanos como la memoria. De estos estudios se han extraído las siguientes conclusiones generales: 1) La tecnología de RV y la inmersión proporcionada por los actuales HMDs son herramientas adecuadas para aplicaciones psicológicas, en particular, la evaluación de la memoria espacial a corto plazo; 2) Un sistema de RV como el presentado podría ser utilizado como herramienta para evaluar o entrenar adultos en habilidades relacionadas con la memoria espacial a corto plazo; 3) Los dos tipos de interacción utilizados para la navegación en el laberinto virtual podrían ser útiles para su uso con diferentes colectivos; 4) El OR permite que los usuarios sin estereopsis puedan percibir l / The evolution of Virtual Reality (VR) technology has contributed in all fields, including psychology. This evolution involves improvements in hardware and software allowing more immersive experiences. In a VR environment users can perceive the sensation of "presence" and feel "immersed". These sensations are possible using VR devices as HMDs. Nowadays, the development of the HMDs has focused on improving their technical features to offer full immersion. In psychology, VR environments are research tools because they allow the use of new paradigms that are not possible to employ in a real environment. There are some applications for assessing spatial memory that use basic methods of HCI. However, VR systems that incorporate stereoscopy and physical movement have not yet been exploited in psychology. In this thesis, a novel VR system combining immersive, interactive and motion features was developed. This system was used for the assessment of the spatial memory and the evaluation of depth perception. For this system, a virtual maze task was designed and implemented. In this system, two different types of interaction were integrated: a locomotion-based interaction pedaling a fixed bicycle (condition1), and a stationary interaction using a gamepad (condition2). This system integrated two types of display systems: 1) The Oculus Rift; 2) A large stereo screen. Two studies were designed to determine the efficacy of the VR system using physical movement and immersion. The first study (N=89) assessed the spatial short term memory using the Oculus Rift and the two types of interaction The results showed that there were statistically significant differences between both conditions. The participants who performed the condition2 got better performance than participants who performed the condition1. However, there were no statistically significant differences in satisfaction and interaction scores between both conditions. The performance on the task correlated with the performance on other classical neuropsychological tests, revealing a verisimilitude between them. The second study (N=59) involved participants who had and who had not stereopsis. This study assessed the depth perception by comparing the two display systems. The participants performed the task using the condition2. The results showed that the different features of the display system did not influence the performance on the task between the participants with and without stereopsis. Statistically significant differences were found in favor of the HMD between the two conditions and between the two groups of participants regard to depth perception. The participants who did not have stereopsis and could not perceive the depth when they used other display systems (e.g. CAVE); however, they had the illusion of depth perception when they used the Oculus Rift. The study suggests that for the people who did not have stereopsis, the head tracking largely influences the 3D experience. The statistical results of both studies have proven that the VR system developed for this research is an appropriate tool to assess the spatial short-term memory and the depth perception. Therefore, the VR systems that combine full immersion, interaction and movement can be a helpful tool for the assessment of human cognitive processes as the memory. General conclusions from these studies are: 1) The VR technology and immersion provided by current HMDs are appropriate tools for psychological applications, in particular, the assessment of spatial short-term memory; 2) A VR system like the one presented in this thesis could be used as a tool to assess or train adults in skills related to spatial short-term memory; 3) The two types of interaction (condition1 and condition2) used for navigation within the virtual maze could be helpful to use with different collectives; 4) The Oculus Rift allows that the users without stereopsis can perceive the depth perception of 3D objects and have rich 3D experiences. / L'evolució de la tecnologia de Realitat Virtual (RV) ha contribuït en tots els camps, incloent la psicologia. Aquesta evolució implica millores en el maquinari i el programari que permeten experiències més immersives. En un entorn de RV, els usuaris poden percebre la sensació de "presència" i sentir-se "immersos". Aquestes sensacions són possibles utilitzant HMDs. Avui dia, el desenvolupament dels HMDs s'ha centrat a millorar les seves característiques tècniques per oferir immersió plena. En la psicologia, els entorns de RV són eines de recerca. Hi ha algunes aplicacions per avaluar la memòria espacial que utilitzen mètodes bàsics d'interacció. Tanmateix, sistemes de RV que incorporen estereoscòpia i moviment físic no s'han explotat en psicologia. En aquesta tesi, s'ha desenvolupat un sistema de RV novell que combina immersió, interacció i moviment. El sistema (tasca en un laberint virtual) s'ha utilitzat per a l'avaluació de la memòria espacial i la percepció de profunditat. S'han integrat dos tipus d'interacció: una interacció basada en locomoció pedalejant una bicicleta fixa (condició1), i l'altra una interacció estacionària usant un gamepad (condició2). S'han integrat dos tipus de sistemes de pantalla: 1) L'Oculus Rift; 2) Una gran pantalla estereoscòpica. Dos estudis van ser dissenyats. El primer estudi (N=89) va avaluar la memòria a curt termini i espacial utilitzant l'Oculus Rift i els dos tipus d'interacció. Els resultats indiquen que hi havia diferències significatives entre les dues condicions. Els participants que van utilitzar la condició2 van obtenir millor rendiment que els participants que van utilitzar la condició1. Tanmateix, no hi havia diferències significatives dins satisfacció i puntuacions d'interacció entre les dues condicions. El rendiment de la tasca va correlacionar amb el rendiment en les proves neuropsicològiques clàssiques, revelant versemblança entre elles. El segon estudi (N=59) va implicar participants que van tenir i que van haver-hi no estereopsis. Aquest estudi va avaluar la percepció de profunditat comparant els dos sistemes de pantalla. Els participants realitzen la tasca utilitzant la condició2. Els resultats van mostrar que les diferents característiques del sistema de pantalla no va influir en el rendiment en la tasca entre els participants qui tenien i els qui no tenien estereopsis. Diferències significatives van ser trobades a favor del HMD entre les dues condicions i entre els dos grups de participants. Els participants que no van tenir estereopsis i no podien percebre la profunditat quan van utilitzar altres sistemes de pantalla (per exemple, CAVE), van tenir la il.lusió de percepció de profunditat quan van utilitzar l'Oculus Rift. L'estudi suggereix que per les persones que no van tenir estereopsis, el seguiment del cap influeix en gran mesura en l'experiència 3D. Els resultats estadístics dels dos estudis han provat que el sistema de RV desenvolupat per aquesta recerca és una eina apropiada per avaluar la memòria espacial a curt termini i la percepció de profunditat. Per això, els sistemes de RV que combinen immersió plena, interacció i moviment poden ser una eina útil per la avaluació de processos cognitius humans com la memòria Les conclusions generals que s'han extret d'aquests estudis, són les següents: 1) La tecnologia de RV i la immersió proporcionada pels HMDs són eines apropiades per aplicacions psicològiques, en particular, la avaluació de memòria espacial a curt termini; 2) Un sistema de RV com el presentat podria ser utilitzat com a eina per avaluar o entrenar adults en habilitats relacionades amb la memòria espacial a curt termini; 3) Els dos tipus d'interacció utilitzats per navegació dins del laberint virtual podrien ser útils per al seu ús amb diferent col.lectius; 3) L'Oculus Rift permet que els usuaris que no tenen estereopsis puguen percebre la percepció de profunditat dels objectes 3D i tenir / Cárdenas Delgado, SE. (2017). VR systems for memory assessment and depth perception [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/94629 / TESIS

No description available.