Page 1. Visual-Vestibular Sensor Integration Follows a Max-Rule: Results from Psychophysical Expe... more Page 1. Visual-Vestibular Sensor Integration Follows a Max-Rule: Results from Psychophysical Experiments in Virtual Reality MPI FOR BIOLOGICAL CYBERNETICS Markus von der Heyde, Bernhard E. Riecke, Douglas W. Cunningham, & Heinrich H. Bülthoff Methods ...
Given that observing one&... more Given that observing one's body is ubiquitous in experience, it is natural to assume that people accurately perceive the relative sizes of their body parts. This assumption is mistaken. In a series of studies, we show that there are dramatic systematic distortions in the perception of bodily proportions, as assessed by visual estimation tasks, where participants were asked to compare the lengths of two body parts. These distortions are not evident when participants estimate the extent of a body part relative to a noncorporeal object or when asked to estimate noncorporal objects that are the same length as their body parts. Our results reveal a radical asymmetry in the perception of corporeal and noncorporeal relative size estimates. Our findings also suggest that people visually perceive the relative size of their body parts as a function of each part's relative tactile sensitivity and physical size. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
ABSTRACT {INTRODUCTION: The prevailing notion of visually induced illusory self-motion perception... more ABSTRACT {INTRODUCTION: The prevailing notion of visually induced illusory self-motion perception (vection) is that the illusion arises from bottom-up perceptual processes. Therefore, past research has focused primarily on examining how physical parameters of the visual stimulus (contrast, number of vertical edges etc.) affect vection. In this study, we examined the influence of a top-down process: Spatial presence in the simulated scene. Spatial presence was manipulated by presenting either a photorealistic image of the Tübingen market place or modified versions of the same stimulus. Modified stimuli were created by either slicing the original image horizontally and randomly reassembling it or by scrambling image parts in a mosaic-like manner. We expected scene modification to decrease spatial presence and thus impair vection. METHODS: Ten naive observers viewed stimuli projected onto a curved projection screen subtending a field of view (FOV) of 54x40.5$textasciicircumtextbackslashcirc$. We measured vection onset times and had participants rate the convincingness of the self-motion illusion for each trial using a 0-100% scale. In addition, we assessed spatial presence using standard presence questionnaires. RESULTS: As expected, scene modification led to both reduced presence scores and impaired vection: Modified stimuli yielded longer vection onset times and lower convincingness ratings than the intact market scene (t(9)=-2.36
We report the effect of cross modal performance on the recognition of familiar objects arranged i... more We report the effect of cross modal performance on the recognition of familiar objects arranged in a scene. In two separate experiments, participants had to learn the position of objects in a scene either by viewing the objects (visual learning) or by feeling the objects (haptic learning). After learning, the experimenter swapped two of seven object positions and the participant's
It is generally believed that the acuity of the peripheral visual field is too poor to allow accu... more It is generally believed that the acuity of the peripheral visual field is too poor to allow accurate object recognition and, that to be identified, most objects need to be brought into foveal vision by using saccadic eye movements. However, most measures of form vision in the periphery have been done at eccentricities below 10∞ and have used relatively artificial
A novel method for feature extraction has been applied to a problem of three-dimensionalobject re... more A novel method for feature extraction has been applied to a problem of three-dimensionalobject recognition (Intrator and Gold, 1991). The method is related to recent statistical theory(Huber, 1985; Friedman, 1987) and is derived from a biologically motivated computationaltheory (Bienenstock et al., 1982). Results of an initial study replicating recent psychophysicalexperiments (Bulthoff and Edelman, 1990) demonstrated the utility of the proposed
Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics, 2012
ABSTRACT The human in manual control of a dynamical system can use both feedback and feedforward ... more ABSTRACT The human in manual control of a dynamical system can use both feedback and feedforward control strategies and will select a strategy based on performance and required effort. Literature has shown that feedforward control is used during tracking tasks in response to predictable targets. The influence of an external disturbance signal on the utilization of a feedforward control strategy has never been investigated, however. We hypothesized that the human will use a combined feedforward and feedback control strategy whenever the predictable target signal is sufficiently strong, and a predominantly feedback strategy whenever the random disturbance signal is dominant. From the data of a human-in-the-loop experiment we conclude that feedforward control is used in all the considered experimental conditions, including those where the disturbance signal is dominant and feedforward control does not deliver a marked performance advantage.
In the course of evolution flies have developed specialized visuomotor programs for tasks like co... more In the course of evolution flies have developed specialized visuomotor programs for tasks like compensating for course deviations, obstacle avoidance, and tracking, which are based on the analysis of visual motion information. In order to test models of the obstacle avoidance behavior in flies, we use computer-simulated agents that evolve parts of their sensor system and sensorimotor coupling with genetic
This paper describes a purely visual navigation scheme based on two elementary mechanisms (piloti... more This paper describes a purely visual navigation scheme based on two elementary mechanisms (piloting and guidance) and a graph structure combining individual navigation steps controlled by these mechanisms. In robot experiments in real environments, both mechanisms have been tested, piloting in an open environment and guidance in a maze with restricted movement opportunities. The results indicate that navigation and path
... performance will cease to be viewpoint invariant; other structural-description theories make ... more ... performance will cease to be viewpoint invariant; other structural-description theories make somewhat similar predictions-see Tarr, 1995). ... Accord-ing to view-based theories,viewpoint-invariant performance is the result of locally diagnostic features. ...
Page 1. Visual-Vestibular Sensor Integration Follows a Max-Rule: Results from Psychophysical Expe... more Page 1. Visual-Vestibular Sensor Integration Follows a Max-Rule: Results from Psychophysical Experiments in Virtual Reality MPI FOR BIOLOGICAL CYBERNETICS Markus von der Heyde, Bernhard E. Riecke, Douglas W. Cunningham, & Heinrich H. Bülthoff Methods ...
Given that observing one&... more Given that observing one's body is ubiquitous in experience, it is natural to assume that people accurately perceive the relative sizes of their body parts. This assumption is mistaken. In a series of studies, we show that there are dramatic systematic distortions in the perception of bodily proportions, as assessed by visual estimation tasks, where participants were asked to compare the lengths of two body parts. These distortions are not evident when participants estimate the extent of a body part relative to a noncorporeal object or when asked to estimate noncorporal objects that are the same length as their body parts. Our results reveal a radical asymmetry in the perception of corporeal and noncorporeal relative size estimates. Our findings also suggest that people visually perceive the relative size of their body parts as a function of each part's relative tactile sensitivity and physical size. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
ABSTRACT {INTRODUCTION: The prevailing notion of visually induced illusory self-motion perception... more ABSTRACT {INTRODUCTION: The prevailing notion of visually induced illusory self-motion perception (vection) is that the illusion arises from bottom-up perceptual processes. Therefore, past research has focused primarily on examining how physical parameters of the visual stimulus (contrast, number of vertical edges etc.) affect vection. In this study, we examined the influence of a top-down process: Spatial presence in the simulated scene. Spatial presence was manipulated by presenting either a photorealistic image of the Tübingen market place or modified versions of the same stimulus. Modified stimuli were created by either slicing the original image horizontally and randomly reassembling it or by scrambling image parts in a mosaic-like manner. We expected scene modification to decrease spatial presence and thus impair vection. METHODS: Ten naive observers viewed stimuli projected onto a curved projection screen subtending a field of view (FOV) of 54x40.5$textasciicircumtextbackslashcirc$. We measured vection onset times and had participants rate the convincingness of the self-motion illusion for each trial using a 0-100% scale. In addition, we assessed spatial presence using standard presence questionnaires. RESULTS: As expected, scene modification led to both reduced presence scores and impaired vection: Modified stimuli yielded longer vection onset times and lower convincingness ratings than the intact market scene (t(9)=-2.36
We report the effect of cross modal performance on the recognition of familiar objects arranged i... more We report the effect of cross modal performance on the recognition of familiar objects arranged in a scene. In two separate experiments, participants had to learn the position of objects in a scene either by viewing the objects (visual learning) or by feeling the objects (haptic learning). After learning, the experimenter swapped two of seven object positions and the participant's
It is generally believed that the acuity of the peripheral visual field is too poor to allow accu... more It is generally believed that the acuity of the peripheral visual field is too poor to allow accurate object recognition and, that to be identified, most objects need to be brought into foveal vision by using saccadic eye movements. However, most measures of form vision in the periphery have been done at eccentricities below 10∞ and have used relatively artificial
A novel method for feature extraction has been applied to a problem of three-dimensionalobject re... more A novel method for feature extraction has been applied to a problem of three-dimensionalobject recognition (Intrator and Gold, 1991). The method is related to recent statistical theory(Huber, 1985; Friedman, 1987) and is derived from a biologically motivated computationaltheory (Bienenstock et al., 1982). Results of an initial study replicating recent psychophysicalexperiments (Bulthoff and Edelman, 1990) demonstrated the utility of the proposed
Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics, 2012
ABSTRACT The human in manual control of a dynamical system can use both feedback and feedforward ... more ABSTRACT The human in manual control of a dynamical system can use both feedback and feedforward control strategies and will select a strategy based on performance and required effort. Literature has shown that feedforward control is used during tracking tasks in response to predictable targets. The influence of an external disturbance signal on the utilization of a feedforward control strategy has never been investigated, however. We hypothesized that the human will use a combined feedforward and feedback control strategy whenever the predictable target signal is sufficiently strong, and a predominantly feedback strategy whenever the random disturbance signal is dominant. From the data of a human-in-the-loop experiment we conclude that feedforward control is used in all the considered experimental conditions, including those where the disturbance signal is dominant and feedforward control does not deliver a marked performance advantage.
In the course of evolution flies have developed specialized visuomotor programs for tasks like co... more In the course of evolution flies have developed specialized visuomotor programs for tasks like compensating for course deviations, obstacle avoidance, and tracking, which are based on the analysis of visual motion information. In order to test models of the obstacle avoidance behavior in flies, we use computer-simulated agents that evolve parts of their sensor system and sensorimotor coupling with genetic
This paper describes a purely visual navigation scheme based on two elementary mechanisms (piloti... more This paper describes a purely visual navigation scheme based on two elementary mechanisms (piloting and guidance) and a graph structure combining individual navigation steps controlled by these mechanisms. In robot experiments in real environments, both mechanisms have been tested, piloting in an open environment and guidance in a maze with restricted movement opportunities. The results indicate that navigation and path
... performance will cease to be viewpoint invariant; other structural-description theories make ... more ... performance will cease to be viewpoint invariant; other structural-description theories make somewhat similar predictions-see Tarr, 1995). ... Accord-ing to view-based theories,viewpoint-invariant performance is the result of locally diagnostic features. ...
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