- •CONTENTS
- •PREFACE
- •Abstract
- •1. Introduction
- •2.1. Differential Geometry of Space Curves
- •2.2. Inverse Problem Formulation
- •2.3. Reconstruction of Unique Space Curves
- •3. Rigid Motion Estimation by Tracking the Space Curves
- •4. Motion Estimation Using Double Stereo Rigs
- •4.1. Single Stereo Rig
- •4.2. Double Stereo Rigs
- •5.1. Space-Time or Virtual Camera Generation
- •5.2. Visual Hull Reconstruction from Silhouettes of Multiple Views
- •5.2.1. Volume Based Visual Hull
- •5.2.1.1. Intersection Test in Octree Cubes
- •5.2.1.2. Synthetic Model Results
- •5.2.2. Edge Base Visual Hull
- •5.2.2.1. Synthetic Model Results
- •Implementation and Exprimental Results
- •Conclusions
- •Acknowledgment
- •References
- •Abstract
- •Introduction: Ocular Dominance
- •Demography of Ocular Dominance
- •A Taxonomy of Ocular Dominance
- •Is Ocular Dominance Test Specific?
- •I. Tests of Rivalry
- •II. Tests of Asymmetry
- •III. Sighting Tests
- •Some Misconceptions
- •Resolving the Paradox of Ocular Dominance
- •Some Clinical Implications of Ocular Dominance
- •Conclusion
- •References
- •Abstract
- •1. Introduction
- •2. Basic Teory
- •3. Bezier Networks for Surface Contouring
- •4. Parameter of the Vision System
- •5. Experimental Results
- •Conclusions
- •References
- •Abstract
- •Introduction
- •Terminology (Definitions)
- •Clinical Assessment
- •Examination Techniques: Motility
- •Ocular Motility Recordings
- •Semiautomatic Analysis of Eye Movement Recordings
- •Slow Eye Movements in Congenital Nystagmus
- •Conclusion
- •References
- •EVOLUTION OF COMPUTER VISION SYSTEMS
- •Abstract
- •Introduction
- •Present-Day Level of CVS Development
- •Full-Scale Universal CVS
- •Integration of CVS and AI Control System
- •Conclusion
- •References
- •Introduction
- •1. Advantages of Binocular Vision
- •2. Foundations of Binocular Vision
- •3. Stereopsis as the Highest Level of Binocular Vision
- •4. Binocular Viewing Conditions on Pupil Near Responses
- •5. Development of Binocular Vision
- •Conclusion
- •References
- •Abstract
- •Introduction
- •Methods
- •Results
- •Discussion
- •Conclusion
- •References
- •Abstract
- •1. Preferential Processing of Emotional Stimuli
- •1.1. Two Pathways for the Processing of Emotional Stimuli
- •1.2. Intensive Processing of Negative Valence or of Arousal?
- •2. "Blind" in One Eye: Binocular Rivalry
- •2.1. What Helmholtz Knew Already
- •2.3. Possible Influences from Non-visual Neuronal Circuits
- •3.1. Significance and Predominance
- •3.2. Emotional Discrepancy and Binocular Rivalry
- •4. Binocular Rivalry Experiments at Our Lab
- •4.1. Predominance of Emotional Scenes
- •4.1.1. Possible Confounds
- •4.2. Dominance of Emotional Facial Expressions
- •4.3. Inter-Individual Differences: Phobic Stimuli
- •4.4. Controlling for Physical Properties of Stimuli
- •4.5. Validation of Self-report
- •4.6. Summary
- •References
- •Abstract
- •1. Introduction
- •2. Algorithm Overview
- •3. Road Surface Estimation
- •3.1. 3D Data Point Projection and Cell Selection
- •3.2. Road Plane Fitting
- •3.2.1. Dominant 2D Straight Line Parametrisation
- •3.2.2. Road Plane Parametrisation
- •4. Road Scanning
- •5. Candidate Filtering
- •6. Experimental Results
- •7. Conclusions
- •Acknowledgements
- •References
- •DEVELOPMENT OF SACCADE CONTROL
- •Abstract
- •1. Introduction
- •2. Fixation and Fixation Stability
- •2.1. Monocular Instability
- •2.2. Binocular Instability
- •2.3. Eye Dominance in Binocular Instability
- •3. Development of Saccade Control
- •3.1. The Optomotor Cycle and the Components of Saccade Control
- •3.4. Antisaccades: Voluntary Saccade Control
- •3.5. The Age Curves of Saccade Control
- •3.6. Left – Right Asymmetries
- •3.7. Correlations and Independence
- •References
- •OCULAR DOMINANCE
- •INDEX
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Georg W. Alpers and Antje B.M. Gerdes |
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3. Previous Investigations of Emotional Pictures
in Binocular Rivalry
3.1. Significance and Predominance
Until recently, very few studies have examined the influence of a pictures’ significance on predominance and suppression in binocular rivalry. An early study by Engel (1956) demonstrated that upright pictures of faces predominate over inverted faces, indicating that greater salience of the familiar upright faces boost their competitive strength in binocular rivalry.
Bagby (1957) investigated the possible influence of personal relevance by showing pairs of pictures containing culturally relevant material to participants with different cultural backgrounds. In North American participants the typically American scene (a baseball player) predominated over less relevant material (a matador) while the latter predominated in participants from Mexican descent. Personal relevance and familiarity thus seem to have an influence on perception in binocular rivalry. However, it has to be acknowledged that response biases (for example whether a picture is easier to specify) have not been taken into account in these studies.
Additional studies further support that perception in binocular rivalry is modulated by personal significance of the stimuli. Kohn (1960) as well as Shelley and Toch (1962) showed that certain personality traits (e.g., aggressiveness) can influence the predominance of related stimuli (violent scenes). It was also reported that depressed participants predominantly perceive pictures with sad content compared to healthy control participants (Gilson, Brown, and Daves, 1982).
Enthusiasm for this paradigm was hampered by other disappointing results. Blake (1988) did not find predominance of meaningful texts over meaningless strings of letters. However, it is important to note that the text elements were not shown at once but as a stream of letters, thus, holistic processing was not possible. Rivalry would have had to occur between non-salient letters of salient words.
Interest in this research paradigm waned for many years after a comprehensive review by Walker (1978) highlighted the methodological problems with early studies. Walker’s main critique was that studies investigating the influence of picture content did not apply stringent definitions of predominance. He concluded that response biases might have been the main cause of the observed results.
Temporarily Blind in One Eye |
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Today, interest in this paradigm has been renewed and a number of well controlled experiments have been conducted since. Results convincingly demonstrate that pictures with a good Gestalt predominate over meaningless pictures (de Weert, Snoeren, and Koning, 2005), and that a meaningful context of pictures promotes predominance (Andrews and Lotto, 2004). Taken together, these investigations more clearly than former studies, support the hypothesis that semantic contents of pictures can affect binocular rivalry.
3.2. Emotional Discrepancy and Binocular Rivalry
Although an influence of semantic content of pictures on binocular rivalry thus seems very likely, there is little evidence that emotional salience can also promote dominance in rivalry. There are few studies in which different emotional pictures were presented stereoscopically. A recent study investigated the effect of different emotional facial expressions on their relative dominance (Coren and Russell, 1992). Here, pairs of pictures showing different facial expressions were presented to one eye each, and after a presentation time of 350 msec participants were asked what their predominant percept was. Facial expressions with strong positive or strong negative valence and high subjective arousal were more frequently perceived as predominant than faces with less extreme ratings. Overall, valence seemed to have had the strongest impact while arousal mainly influences dominance when the rivalling pictures had the same valence. It is problematic that only emotional faces were presented together and the presentation time was very short, because binocular rivalry takes time to built up. Moreover, asking the participants about their percept after the presentation introduced sources of error such as memory effects and response biases.
Another study investigated perception of different facial expressions in binocular rivalry but its aim was to document the two-dimensional structure of emotions (on scales of valence and arousal) and predominance of emotional pictures was not the center of its design (Ogawa, Takehara, Monchi, Fukui, and Suzuki, 1999). Pairs of pictures with different emotional facial expressions were presented and the perceived impression was rated for valence and arousal. A second and very similar study by the same group measured specific perceptual impressions during the presentation in addition to the dimensional structure of the evaluations (Ogawa and Suzuki, 2000). The authors conclude that there is more rivalry between pictures which are evaluated similarly on valence and arousal, while pictures with stronger valence and superior arousal are more unambiguously perceived as dominant.