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We describe a method to solve the stereo correspondence using controlled eye (or camera) movements. These eye movements essentially supply additional image frames which can be used to constrain the stereo matching. Because the eye movements are small, traditional methods of stereo with multiple frames will not work. We develop an alternative approach using a systematic analysis to define a probability distribution for the errors. Our matching strategy then matches the most probable points first, thereby reducing the ambiguity for the remaining matches. We demonstrate this algorithm with several examples.

Japanese particles have been studied syntactically and semantically in connection with preceding words for constructing sentence, and studied in terms of predicate in connection with core meaning of the noun. However, the role of particles in the field of reading has not clearly been explained. This dissertation investigates the role of Japanese particles for L2 and L1 readers reading aloud through the following questions: (1) In what ways do L 2 and L1 Japanese readers miscue on particles? (2) Why do L2 and L1 Japanese readers elongate the phoneme of the particle? (3) How do L2 and L1 Japanese readers' eye movements show fixation points on particles? (4) How do L2 and L1's Japanese readers' miscues of particles relate to the L2 and L1 readers' eye movements? (5) How do L2 and L1 readers' fixation points on particles relate to elongation? (6) How do L2 and L1 Japanese readers' fixation points relate to miscues and elongation? Five L2 and four L1 readers read a Japanese story that included 121 particles. By looking at miscues, the results show the segmentation process using particles. This segmentation process minimizes the number of particle miscues. Substitution, omission, and insertion miscues occur in a complex manner because they are related to finding word boundaries. Elongation occurs as a process of prediction and confirmation for making sense. L2 readers use elongation with miscues more often than L1 readers. In eye movement research, L2 reader's miscues are more highly connected to eye fixation than are L1 readers' miscues. Eye fixation points and elongation are used for prediction and confirmation for making sense. However, L1 readers' miscues mainly consist of fixation without elongation. L2 readers use more particles while L1 readers use more flexible construction with the meaning of adjacent words playing an important role. Readers do not just fixate, but also elongate particles to get information. The result shows that readers use miscues on particles, elongation, and eye fixations as complex processes to construct a meaningful text.

Theories of age-related memory decline debate whether the problem lies at the level of encoding or consciously accessing information at the level of retrieval. Deficits at encoding may be due to the inability to bind relations among objects. The present research implements eye movement monitoring into an associative memory task to explore age-related memory at encoding and retrieval. Eye movements of older and younger adults are compared. Three solitary items were presented during the study phase, and test responses were whether the spatial relation of these objects to one another was intact or manipulated when subsequently presented all together. Observed differences at the level of encoding in addition to the level of retrieval clarifies that there is not a deficit in consciously accessing encoded representations. Further, differences in relational binding at the level of encoding were observed, which supports the association deficit theory of memory and aging.

The experiments studied the ability to perceive visual, events of a very simple kind: the appearance and disappearance of isolated dots in random dot patterns. The aim of the investigation was to explore the limits of this ability and clarify the relationship, between event perception and sensory storage. The first series of experiments studied the ability to detect the appearance and disappearance of single dots. Under appropriate conditions such changes can be detected in a pattern containing 1024 dots with 98% accuracy. This level of accuracy was largely maintained over manipulation of the number of dots in the pattern, pattern size and separation between dots. Performance was unaffected by whether pattern luminance was uniform or not. It is argued that to explain this performance the notion of sensory integration must be augmented by the concept of sensory differentiation. The ability to detect events was further investigated as a function of pattern complexity and ISI. The storage underlying event detection has a very high capacity and a short duration. The second series of experiments investigated the ability to perceive patterns of events. Letters defined by either appearances or disappearances were accurately identified; thus a pattern which was not visible was made visible by its disappearance. A measure of localization was obtained by requiring subjects to judge whether three events were aligned. It is concluded that both onset and offset of a pattern convey information about form but that acuity for events is poorer than for sustained stimuli. The possibility that event perception is achieved by integration at short stimulus durations was investigated by varying the durations of the patterns before and after the events. Little evidence for event perception by integration was found; increasing the durations of the patterns either improved performance or had little or no effect on it. The final experiment examined a conflict between the present results and studies of visual integration. The ability to perceive mixtures of appearances and disappearances was investigated and found to be poorer than the ability to process either type of event alone. The ability to detect and locate events is highly developed. This ability seems well adapted to the detection and perception of significant change in the natural environment. In contrast to the increasing scepticism concerning the function of sensory storage it is concluded that event perception is an important visual function in which sensory storage is clearly implicated.

Theories of age-related memory decline debate whether the problem lies at the level of encoding or consciously accessing information at the level of retrieval. Deficits at encoding may be due to the inability to bind relations among objects. The present research implements eye movement monitoring into an associative memory task to explore age-related memory at encoding and retrieval. Eye movements of older and younger adults are compared. Three solitary items were presented during the study phase, and test responses were whether the spatial relation of these objects to one another was intact or manipulated when subsequently presented all together. Observed differences at the level of encoding in addition to the level of retrieval clarifies that there is not a deficit in consciously accessing encoded representations. Further, differences in relational binding at the level of encoding were observed, which supports the association deficit theory of memory and aging.

Treatise (D.M.A.) -- Florida State University, 2004. / Advisor: Douglas Fisher, Florida State University, School of Music. Title and description from treatise home page (viewed 9-29-04). Document formatted into pages; contains 73 pages. Includes biographical sketch. Includes bibliographical references.

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Humans must regularly locate task-relevant objects when interacting with the world around them. Previous research has identified different types of information that the visual system can use to help locate objects in real-world scenes, including low-level image features and scene context. However, previous research using object arrays suggest that there may be another type of information that can guide real-world search: target knowledge. When a participant knows what a target looks like they generate and store a visual representation, or template, of it. This template then facilitates the search process. A complete understanding of real-world search needs to identify how a target template guides search through scenes. Three experiments in Chapter 2 confirmed that a target template facilitates realworld search. By using an eye-tracker target knowledge was found to facilitate both scanning and verification behaviours during search, but not the search initiation process. Within the scanning epoch a target template facilitated gaze directing and shortened fixation durations. These results suggest that target knowledge affects both the activation map, which selects which regions of the scene to fixate, and the evaluation process that compares a fixated object to the internal representation of the target. With the exact behaviours that a target template facilitates now identified, Chapter 3 investigated the role that target colour played in template-guided search. Colour is one of the more interesting target features as it has been shown to be preferred by the visual system over other features when guiding search through object arrays. Two real-world search experiments in Chapter 3 found that colour information had its strongest effect on the gaze directing process, suggesting that the visual system relies heavily on colour information when searching for target-similar regions in the scene percept. Although colour was found to facilitate the evaluation process too, both when rejecting a fixated object as a distracter and accepting it as the target, this behaviour was found to be influenced comparatively less. This suggests that the two main search behaviours – gaze directing and region evaluation – rely on different sets of template features. The gaze directing process relies heavily on colour information, but knowledge of other target features will further facilitate the evaluation process. Chapter 4 investigated how target knowledge combined with other types of information to guide search. This is particularly relevant in real-world search where several sources of guidance information are simultaneously available. A single experiment investigated how target knowledge and scene context combined to facilitate search. Both information types were found to facilitate scanning and verification behaviours. During the scanning epoch both facilitated the eye guidance and object evaluation processes. When both information sources were available to the visual system simultaneously, each search behaviour was facilitated additively. This suggests that the visual system processes target template and scene context information independently. Collectively, the results indicate not only the manner in which a target template facilitates real-world search but also updates our understanding of real-world search and the visual system. These results can help increase the accuracy of future realworld search models by specifying the manner in which our visual system utilises target template information, which target features are predominantly relied upon and how target knowledge combines with other types of guidance information.

The traditional view of vision is that neurons in early cortical areas process information about simple features (e.g. orientation and spatial frequency) in small, spatially localised regions of visual space (the neuron's receptive field). This piecemeal information is then fed-forward into later stages of the visual system where it gets combined to form coherent and meaningful global (higher-level) representations. The overall aim of this thesis is to examine and quantify this higher level processing; how we encode global features in natural images and to understand the extent to which our perception of these global representations is determined by the local features within images. Using the tilt after-effect as a tool, the first chapter examined the processing of a low level, local feature and found that the orientation of a sinusoidal grating could be encoded in both a retinally and spatially non-specific manner. Chapter 2 then examined these tilt aftereffects to the global orientation of the image (i.e., uprightness). We found that image uprightness was also encoded in a retinally / spatially non-specific manner, but that this global property could be processed largely independently of its local orientation content. Chapter 3 investigated if our increased sensitivity to cardinal (vertical and horizontal) structures compared to inter-cardinal (45° and 135° clockwise of vertical) structures, influenced classification of unambiguous natural images. Participants required relatively less contrast to classify images when they retained near-cardinal as compared to near-inter-cardinal structures. Finally, in chapter 4, we examined category classification when images were ambiguous. Observers were biased to classify ambiguous images, created by combining structures from two distinct image categories, as carpentered (e.g., a house). This could not be explained by differences in sensitivity to local structures and is most likely the result of our long-term exposure to city views. Overall, these results show that higher-level representations are not fully dependent on the lower level features within an image. Furthermore, our knowledge about the environment influences the extent to which we use local features to rapidly identify an image.