Many virtual reality (VR) researchers consider exact head registration (HR) and an exact multi-sensory alignment between real world and virtual objects to be a critical factor for effective motor performance in VR. Calibration procedures, however, can be error prone, time consuming and sometimes impractical to perform. To better understand the relationship between head registration and fine motor performance, we conducted a series of reciprocal tapping tasks under four conditions: real world tapping, VR with correct HR, VR with mildly perturbed HR, and VR with highly perturbed HR. As might be expected, VR performance was worse than real world performance. There was no effect of HR perturbation on motor performance in the tapping tasks. We believe that sensorimotor adaptation enabled subjects to perform equally well in the three VR conditions despite the incorrect head registration in two of the conditions. This suggests that exact head registration may not be as critically important as previously thought, and that extensive per-user calibration procedures may not be necessary for some VR tasks.

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This is a practical and theoretical thesis in visual robotics. It describes the development and actual implementation (in a real world, real-time visual robot) of new approaches to three non-linear problems: how to ensure robustness under the harshest conditions of unforeseen reconfiguration, how to provide specialised space-variant sampling regimes according to which task is currently at hand, and how to automatically direct attention using any number of adaptive response layers in concert. Additionally, the descriptions of this practical work are preceded by the exposition of a new theoretical framework for intelligent system evaluation, which offers performance silhouettes as a schematic method. The three practical methods stem from, and are embedded in, the theoretical framework, and all have been suggested, to varying degrees, by knowledge of biological processes or capabilities- self-organisation, visual periphery sensitivity, and adaptive reduction in sensitivity, for example. The overall goal of the research is to develop extremely simple algorithms capable of operating in real-time and endowing a robot with robust essential perceptual capabilities that can operate in all environments. The outcome of the work is a visual robotic system that exhibits seemingly intelligent behaviour in complex, changing, and noisy natural environments. That it does so with minimal help from other sophisticated agents (such as computer science researchers) is a credit to its autonomy and the adaptation of its design to arbitrary environments.

Abstract — Inspired by the pioneering work by Held and Hein (1963) on the development of kitten visuo-motor systems, we explore the role of active body movement in the developmental process of the visual system by using robots. The receptive fields in an evolved mobile robot are developed during active or passive movement with a Hebbian learning rule. In accordance to experimental observations in kittens, we show that the receptive fields and behavior of the robot developed under active condition significantly differ from those developed under passive condition. A possible explanation of this difference is derived by correlating receptive field formation and behavioral performance in the two conditions. ∗ I.

Many virtual reality researchers consider exact head registration and an exact multi-sensory alignment between real world and virtual objects to be a critical factor for ef-fective motor performance in a virtual environment. Calibration procedures for head-mounted displays, however, can be error prone, time consuming and sometimes im-practical to perform. To better understand the relationship between head registration and fine motor performance, we conducted a series of reciprocal tapping tasks under four conditions: real world tapping, virtual reality with correct head registration, virtual reality with mildly perturbed head registration, and virtual reality with highly perturbed head registration. As might be expected, virtual reality performance was worse than real world performance. There was no effect of head registration perturbation on motor performance in the tapping tasks. We believe that sensorimotor adaptation enabled sub-jects to perform equally well in the three virtual reality conditions despite the incorrect head registration in two of the conditions. This suggests that exact head registration may not be as critically important as previously thought, and that extensive per-user calibration procedures may not be necessary for some virtual reality tasks. ii

Abstract. Not all empirical work in the psychology of perception has operated explicitly within a theoretical framework. But when it has, that framework has usually been provided by the inferential theory of perception. I argue that in spite of its explanatory strengths, the inferential theory of perception conceals a well-established empirical phenomenon. That phenomenon is known in ordinary parlance as ‘familiarity’. I discuss why the inferential theory of perception cannot deal with familiarity and what it reveals about the limits of the inferential theory of perception. Key Words: familiarity, Gregory, illusion decrement, inferential theory of perception In the last fifteen years or so, an alternative to cognitivism has been making some headway. Being new, the alternative is not well formed, but it is a vigorous research program, operating on many fronts. To simply call it ‘anticognitivism’ would be too broad, for that would include behaviorists and Freudians. The new anti-cognitivists want to distance themselves from those

This paper offers an approach to social cognitive development intended to address the above discrepancy, which is considered a key element for any understanding of the pathophysiology of autism

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Evidence for an eye-centered spherical representation of the visuomotor

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