Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 156-168).

In low-level vision, the representation of scene properties such as shape, albedo, etc., are very high dimensional as they have to describe complicated structures. The approach proposed here is to let the image itself bear as much of the representational burden as possible. In many situations, scene and image are closely related and it is possible to find a functional relationship between them. The scene information can be represented in reference to the image where the functional specifies how to translate the image into the associated scene. We illustrate the use of this representation for encoding shape information. We show how this representation has appealing properties such as locality and slow variation across space and scale. These properties provide a way of improving shape estimates coming from other sources of information like stereo.

This article describes a model for including scene/context priors in attention guidance. In the proposed scheme, visual context information can be available early in the visual processing chain, in order to modulate the saliency of image regions and to provide an efficient short cut for object detection and recognition. The scene is represented by means of a low-dimensional global description obtained from low-level features. The global scene features are then used to predict the probability of presence of the target object in the scene, and its location and scale, before exploring the image. Scene information can then be used to modulate the saliency of image regions early during the visual processing in order to provide an efficient short cut for object detection and recognition.

The human visual system is adept at detecting and encoding statistical regularities in its spatio-temporal environment. Here we report an unexpected failure of this ability in the context of perceiving inconsistencies in illumination distributions across a scene. Contrary to predictions from previous studies [Enns and Rensink, 1990; Sun and Perona, 1996a, 1996b, 1997], we find that the visual system displays a remarkable lack of sensitivity to illumination inconsistencies, both in experimental stimuli and in images of real scenes. Our results allow us to draw inferences regarding how the visual system encodes illumination distributions across scenes. Specifically, they suggest that the visual system does not verify the global consistency of locally derived estimates of illumination direction.

In the absence of cues for absolute depth measurements as binocular disparity, motion, or defocus, the absolute distance between the observer and a scene cannot be measured. The interpretation of shading, edges and junctions may provide a 3D model of the scene but it will not inform about the actual "size" of the space. One possible source of information for absolute depth estimation is the image size of known objects. However, this is computationally complex due to the difficulty of the object recognition process. Here we propose a source of information for absolute depth estimation that does not rely on specific objects: we introduce a procedure for absolute depth estimation based on the recognition of the whole scene. The shape of the space of the scene and the structures present in the scene are strongly related to the scale of observation. We demonstrate that, by recognizing the properties of the structures present in the image, we can infer the scale of the scene, and therefore its absolute mean depth. We illustrate the interest in computing the mean depth of the scene with application to scene recognition and object detection.

Ralph Vaughan Williams (1872-1958) was one of the most prolific British composers of the twentieth century, yet his operas are virtually unknown in the standard operatic repertoire. Singers and teachers of singing are often challenged in finding operatic arias composed in the English language, because the standard operatic repertoire simply does not have as many works originally written in English as are found in Italian, German, or French. If there are arias from Vaughan Williams’ operas that are accessible to the young singing voice, they should not remain unknown. This study was executed in hopes of identifying for singers and teachers of singing, the arias, duets and scenes for male voice that can stand alone outside performances of the operas. The implications of this research project are that singers and teachers of singing have a newly found wealth of repertoire to utilize in performance as well as in the learning environment. Not only are these findings beautiful music from one of the twentieth century’s most prominent composers, but they are perhaps more importantly, accessible to the young and developing singer.

Recent research has revealed many similarities between episodic memory, scene construction, and imagination of the future. It has been suggested that scene construction is the common process underlying memory and imagination, but no study to date has directly compared all three abilities. The present study compared retrieval time, ratings of detail and vividness for episodic memories, remembered scenes and imagined future events cued by landmarks of high and low familiarity. Memories, scenes, and imagined episodes based on a more familiar landmark as a cue were more quickly retrieved, more detailed, and more vivid. This study was the first to demonstrate the effects of frequent encounters with a cue on memory, scene construction and imagination of the future. Additionally, consistent results across conditions, as well as stronger effects in the scene construction condition, provide further evidence of a possible interdependence of episodic memory, imagination of the future, and scene construction.

Current theories of auditory attention are largely based upon studies examining either the presentation of a single auditory stimulus or requiring the identification and labeling of stimuli presented sequentially. Whether or not these theories apply in more complex ecologically-valid environments where multiple sound sources are simultaneously active is still unknown. This study examined the pattern of neuromagnetic responses elicited when participants had to perform a search in an auditory language-based `scene` for a stimulus matching an imperative target held in working memory. The analysis of source waveforms revealed left lateralized patterns of activity that distinguished target present from target absent trials. Similar source waveform amplitudes were found when the target was presented in the left or right hemispace. The results suggest that auditory search for speech sounds engage a left lateralized process in the superior temporal gyrus.

Recent research has revealed many similarities between episodic memory, scene construction, and imagination of the future. It has been suggested that scene construction is the common process underlying memory and imagination, but no study to date has directly compared all three abilities. The present study compared retrieval time, ratings of detail and vividness for episodic memories, remembered scenes and imagined future events cued by landmarks of high and low familiarity. Memories, scenes, and imagined episodes based on a more familiar landmark as a cue were more quickly retrieved, more detailed, and more vivid. This study was the first to demonstrate the effects of frequent encounters with a cue on memory, scene construction and imagination of the future. Additionally, consistent results across conditions, as well as stronger effects in the scene construction condition, provide further evidence of a possible interdependence of episodic memory, imagination of the future, and scene construction.

Current theories of auditory attention are largely based upon studies examining either the presentation of a single auditory stimulus or requiring the identification and labeling of stimuli presented sequentially. Whether or not these theories apply in more complex ecologically-valid environments where multiple sound sources are simultaneously active is still unknown. This study examined the pattern of neuromagnetic responses elicited when participants had to perform a search in an auditory language-based `scene` for a stimulus matching an imperative target held in working memory. The analysis of source waveforms revealed left lateralized patterns of activity that distinguished target present from target absent trials. Similar source waveform amplitudes were found when the target was presented in the left or right hemispace. The results suggest that auditory search for speech sounds engage a left lateralized process in the superior temporal gyrus.