Change blindness: eradication of gestalt strategies

Arrays of eight, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB) task where there was a 50% chance that one rectangle would change orientation between two successive presentations separated by an interval. CB was eliminated by cueing the target rectangle in the first stimulus, reduced by cueing in the interval and unaffected by cueing in the second presentation. This supports the idea that a representation was formed that persisted through the interval before being 'overwritten' by the second presentation (Landman et al, 2003 Vision Research 43149–164]. Another possibility is that participants used some kind of grouping or Gestalt strategy. To test this we changed the spatial position of the rectangles in the second presentation by shifting them along imaginary spokes (by ±1 degree) emanating from the central fixation point. There was no significant difference seen in performance between this and the standard task [F(1,4)=2.565, p=0.185]. This may suggest two things: (i) Gestalt grouping is not used as a strategy in these tasks, and (ii) it gives further weight to the argument that objects may be stored and retrieved from a pre-attentional store during this task

Haptics Rendering and Applications

There has been significant progress in haptic technologies but the incorporation of haptics into virtual environments is still in its infancy. A wide range of the new society's human activities including communication, education, art, entertainment, commerce and science would forever change if we learned how to capture, manipulate and reproduce haptic sensory stimuli that are nearly indistinguishable from reality. For the field to move forward, many commercial and technological barriers need to be overcome. By rendering how objects feel through haptic technology, we communicate information that might reflect a desire to speak a physically- based language that has never been explored before. Due to constant improvement in haptics technology and increasing levels of research into and development of haptics-related algorithms, protocols and devices, there is a belief that haptics technology has a promising future

Adjusting Haptic Guidance to Idiosyncratic Visuo-Haptic Matching Errors Improves Perceptual Consistency in Reaching

When subjects reach for a visual target with their unseen hand, they make systematic errors (visuo-haptic matching errors). Visuohaptic matching errors are idiosyncratic and consistent over time. Therefore, it might be useful to compensate for these subject-specific matching errors in the design of haptic guidance to make the guidance perceptually consistent with the visual information. In this study, we investigated whether compensating for visuo-haptic matching errors results in better perceptual consistency in a reaching task. Subjects (N = 12) had to reach for visual targets with the handle of a haptic device (PHANToM Premium 3.0/6DoF) held in their unseen dominant hand without guidance, with haptic guidance toward the target position, or with haptic guidance toward the position they would reach for according to their idiosyncratic visuo-haptic matching error.We found that the distance between the aiming point of the guidance and the reached end position was smaller for the guidance toward the idiosyncratic matched positions, suggesting a larger perceptual consistency. Adjusting for idiosyncratic visuo-haptic matching errors seems to have benefits over guidance to the visual target position

Activity in area V3A predicts positions of moving objects

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Tactile sensitivity in typical and atypical development

Ph. D. ThesisThe tactile sense is fundamental for typical development yet has been largely under studied in comparison to other sensory modalities of vision and audition. Some individuals exhibit unusual behavioural responses to sensory stimulation that would normally not be considered to be noxious. There has been an increase in research exploring these unusual sensory abnormalities over the last 10 years. Previously only reported anecdotally, some individuals are aversive to or withdraw from tactile stimulation. Referred to as tactile This thesis aims to explore tactile sensitivity in typically developing individuals and those individuals most likely to have sensory abnormalities, specifically Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). Chapter one summarises literature on the importance of touch for development and introduces theories of tactile defensiveness. A questionnaire study explores texture preferences and aversions in Chapter two. Since little is known about texture preference in either typically developing children or those with ASD / ADHD the purpose of the questionnaire was to create a baseline of texture preference. A further study explored preference for texture complexity. Contrary to expectation, no differences in texture preference were found between comparison groups. Since no differences in texture preference were found, it was predicted that perhaps differences in unusual tactile response may be due to heightened sensitivity to texture for those individuals with sensory abnormalities. Chapter three investigated tactile sensitivity to fine texture and predicted that individuals with ASD would be more accurate at texture discrimination than typically developing individuals. No group difference was found in texture discrimination. In Chapter four, cross-modal matching of texture was explored. It was proposed that unusual tactile response observed in individuals with ASD may be due to difficulty matching visual and tactual information. In a series of studies, results found that individuals with ASD were impaired at matching texture information cross-modally. The inability to accurately match visual-tactual texture information may contribute to the negative tactile reactions observed in individuals with ASD and may provide insight into a possible contributing factor to tactile sensitivity in atypical development.defensiveness, this unusual tactile response has been explored primarily with the use of questionnaires. Literature reports both over-responsivity (hyper) and under-responsivity (hypo) to tactile stimulation in atypical development, for example exhibiting negative response to social touch or an extreme fascination with certain tactile stimulation. Tactile defensiveness affects many facets of behaviour, including motor development, learning and social interaction. In some extreme cases, individuals with tactile defensiveness will avoid human contact. To date, there is no systematic research examining tactile sensitivity in typical or atypical development despite these negative consequences for many aspects of development

Sonic interactions in virtual environments

This book tackles the design of 3D spatial interactions in an audio-centered and audio-first perspective, providing the fundamental notions related to the creation and evaluation of immersive sonic experiences. The key elements that enhance the sensation of place in a virtual environment (VE) are: Immersive audio: the computational aspects of the acoustical-space properties of Virutal Reality (VR) technologies Sonic interaction: the human-computer interplay through auditory feedback in VE VR systems: naturally support multimodal integration, impacting different application domains Sonic Interactions in Virtual Environments will feature state-of-the-art research on real-time auralization, sonic interaction design in VR, quality of the experience in multimodal scenarios, and applications. Contributors and editors include interdisciplinary experts from the fields of computer science, engineering, acoustics, psychology, design, humanities, and beyond. Their mission is to shape an emerging new field of study at the intersection of sonic interaction design and immersive media, embracing an archipelago of existing research spread in different audio communities and to increase among the VR communities, researchers, and practitioners, the awareness of the importance of sonic elements when designing immersive environments

Sonic Interactions in Virtual Environments

This open access book tackles the design of 3D spatial interactions in an audio-centered and audio-first perspective, providing the fundamental notions related to the creation and evaluation of immersive sonic experiences. The key elements that enhance the sensation of place in a virtual environment (VE) are: Immersive audio: the computational aspects of the acoustical-space properties of Virutal Reality (VR) technologies Sonic interaction: the human-computer interplay through auditory feedback in VE VR systems: naturally support multimodal integration, impacting different application domains Sonic Interactions in Virtual Environments will feature state-of-the-art research on real-time auralization, sonic interaction design in VR, quality of the experience in multimodal scenarios, and applications. Contributors and editors include interdisciplinary experts from the fields of computer science, engineering, acoustics, psychology, design, humanities, and beyond. Their mission is to shape an emerging new field of study at the intersection of sonic interaction design and immersive media, embracing an archipelago of existing research spread in different audio communities and to increase among the VR communities, researchers, and practitioners, the awareness of the importance of sonic elements when designing immersive environments

Sonic Interactions in Virtual Environments

This open access book tackles the design of 3D spatial interactions in an audio-centered and audio-first perspective, providing the fundamental notions related to the creation and evaluation of immersive sonic experiences. The key elements that enhance the sensation of place in a virtual environment (VE) are: Immersive audio: the computational aspects of the acoustical-space properties of Virutal Reality (VR) technologies Sonic interaction: the human-computer interplay through auditory feedback in VE VR systems: naturally support multimodal integration, impacting different application domains Sonic Interactions in Virtual Environments will feature state-of-the-art research on real-time auralization, sonic interaction design in VR, quality of the experience in multimodal scenarios, and applications. Contributors and editors include interdisciplinary experts from the fields of computer science, engineering, acoustics, psychology, design, humanities, and beyond. Their mission is to shape an emerging new field of study at the intersection of sonic interaction design and immersive media, embracing an archipelago of existing research spread in different audio communities and to increase among the VR communities, researchers, and practitioners, the awareness of the importance of sonic elements when designing immersive environments