Human beings live and work in large and complex environments. It is often difficult for individuals to perceive and understand the structure of these environments. However, the formation of an accurate and reliable cognitive map, a mental model of the environment, is vital for optimal navigation and coordination. The need to develop a reliable cognitive map is common to the average individual as well as workers with more specialized tasks, for example, law enforcement or military personnel who must quickly learn to operate in a new area. In this dissertation, I propose the use of a wearable computer as a platform for a spatial cognition aid. This spatial cognition aid uses terrain visualization software, GPS positioning, orientation sensors, and an eyeglass mounted display to provide an overview of the surrounding environment. While there are a number of similar mobile or wearable computer systems that function as tourist guides, navigation aids, and surveying tools, there are few examples of spatial cognition aids. I present an architecture for the wearable computer based spatial cognition aid using a relationship mediation model for wearable computer applications. The relationship mediation model identifies and describes the user relationships in which a wearable computer can participate and mediate. The dissertation focuses on how the wearable computer mediates the users perception of the environment. Other components such as interaction techniques and a scalable system of servers for distributing spatial information are also discussed. Several user studies were performed to determine an effective presentation for the spatial cognition aid. Participants were led through an outdoor environment while using different presentations on a wearable computer. The spatial learning of the participants was compared. These studies demonstrated that a wearable computer can be an effective spatial cognition aid. However, factors such as such as mental rotation, cognitive load, distraction, and divided attention must be taken into account when presenting spatial information to a wearable computer user.

It is well established in mammals that chronic, long-term elevations in sex steroids are associated with improvements in spatial cognition. It is less clear the extent to which short to medium term elevations in sex steroids improve spatial cognition and change hippocampal morphology, particularly in birds. The avian hippocampus expresses both androgen receptors (AR) and oestrogen receptor alpha (ERα) and high levels of the enzyme aromatase that converts testosterone to oestrogen. I began by comparing spatial cognition, hippocampal sex steroid receptor and aromatase expression between males and females. There were no differences in spatial or visual cognition or in hippocampal sex steroid receptor expression between the sexes, although hippocampal aromatase mRNA expression was higher in males. I then addressed the effects of acute and medium-term sex steroid treatment on spatial cognition and hippocampal aromatase and sex steroid receptor expression. A single treatment of testosterone 30 minutes or four hours prior to cognitive testing improved spatial performance. Additionally, when testosterone and oestrogen were given daily for five days spatial cognition in both sexes was improved. The testosterone-induced improvement was blocked when testosterone was administered in conjunction with the aromatase inhibitor fadrozole but not when administered with saline. These findings suggest that spatial cognition is improved by an oestrogenic effect. Thirty minutes following acute testosterone treatment, plasma testosterone levels, hippocampal AR and ERα mRNA expression all increased. Five days of oestrogen treatment increased plasma oestrogen levels, hippocampal ERα mRNA and Nmethyl- D-aspartate (NMDA) receptor levels in males and females; all were positively correlated with enhanced spatial cognition on day five of treatment. Finally, I determined which genes were differentially expressed as a result of five days of oestrogen treatment. Nineteen genes, identified as being involved in learning and memory were differentially expressed in the hippocampus, eleven of which were up-regulated and eight were down-regulated. Taken together these results demonstrate that oestrogen can improve spatial cognition in birds. It is plausible that oestrogen acts to improve spatial memory in the hippocampus through upregulation of genes that control neurotransmitter release, reuptake and receptor levels.

Thesis (Ph. D.)--Miami University, Dept. of Psychology, 2009. / Title from second page of PDF document. Includes bibliographical references (p. 42-49).

Thesis (M.A.)--Miami University, Dept. of Psychology, 2005. / Title from first page of PDF document. Document formatted into pages; contains [1], iv, 35 p. : ill. Includes bibliographical references (p. 32-35).

In this thesis the spatial cognitive experiment with great tits (Parus major) as a model species is described. In this experiment tits learnt to respond to one of four response keys according the presented stimuli. Two types of stimuli were used: one of them contained configural information about response keys, but the other didn´t. The experiment tested the difference of using these two types of spatial information in great tits in two experimental designs. In the first design stimuli were presented in computer screen, in the other they were presented in the floor of experimental chamber. The thesis then discusses the performance of tits in two types of stimuli and two versions of experimental design and compares these results with pigeons in similar experiment.

In this research we introduce a novel reading system that enables Individuals with Blindness<br />or Severe Visual Impairment (IBSVI) to have equivalent spatial reading experience to their<br />sighted counterparts, in terms of being able to engage in different reading strategies e.g.<br />scanning, skimming, and active reading. IBSVI are enabled to read in a self-paced manner<br />with spatial access to the original layout of any electronic text document. This system<br />renders text on iPad-type devices, and reads aloud each word touched by the user\'s finger.<br />The user could move her finger smoothly along the lines to read continuously with the<br />support of tactile landmarks. A tactile overlay on the iPad screen helps IBSVI to navigate<br />a page, furnishing a framework of tactile landmarks to give IBSVI a sense of place on the<br />page. As the user moves her finger along the tangible pattern of the overlay, the text on the<br />screen that is touched is rendered audibly to speech. The system supports IBSVI to develop<br />and maintain a cognitive map of the structure and the layout of the page. IBSVI are enabled<br />to fuse audio, tactile landmarks, and spatial information in order to read.<br />The system\'s initial design is founded on a theoretical hypothesis. A participatory design<br />approach with IBSVI consultants was then applied to refine the initial design. The re"fined<br />design was tested in a usability study, which revealed two major issues with the tested<br />design. These issues are related to the lack of instant feedback from the system (psycho-<br />motorical problem), and the lack of conveying the semantic level of the page structure.<br />We adapted the reader design to solve the usability problems. The improved design was<br />tested in an experience sampling study. The results showed a leap in the system usability.<br />IBSVI participants successfully self-paced read spatial text. Further reading support was<br />then added to the system to improve the user experience while reading and interacting with<br />the system. We tested the latest design of the reader system with respect to its featured<br />function of enabling self-paced reading and re-finding information. A decomposition study<br />was conducted to evaluate the main components of the system; the tactile overlay, and the<br />intelligent active reading support. The results showed that both components are required<br />to achieve the best performance in terms of efficiency, effectiveness, and spatial perception.<br />We conducted an evaluation study to compare our reader system to the state-of-the-art<br />iBook with VoiceOver. The results show that our reader system is more effective than iBook<br />with VoiceOver in finding previously read information and in estimating the layout of the<br />page, implying that IBSVI were able to construct a cognitive map for the pages they read,<br />and perform advanced reading strategies. Our goal is to to enable IBSVI to access digital<br />reading materials effectively, so that they may have equal learning opportunities as their<br />sighted counterparts. / Ph. D.

Spatial orientation of pigeons on a small scale was intensivelly studied in experiments using various types of arenas or mazes. In these experiments pigeons usually searched for food hidden in the goal area and they based their orientation on available landmarks. The development of new technologies allowed to test spatial cognition of pigeons also in virtual tasks, based exclusively on a schematic representation of an arena or maze on a touch screen. In experiments of this type pigeon marks the goal by pecking and it is rewarded by food from a feeder, located near the monitor. Study presented in this diploma thesis was based on combination of both types of spatial tasks. The information crucial for locating the goal was presented to pigeons on a computer screen in form of graphic stimuli, whereas the goal itself was formed by one of the 4 holes in corners of a transparent rectangular desk, standing in front of the monitor. Experiment with similar design was not yet published in the study of spatial cognition of pigeons. Two types of abstract graphic stimuli were tested. The first stimuli provided a spatial information about the location of a goal and had a form of small rectangular frame with a white spot in one of its corners. The frame represented the space of the response desk and the white spot...

Diploma thesis generally compares individual success pigeons in spatial tasks of varying complexity (in a role that requires abstraction of visual stimuli representing spatial relationships on the touch screen using two different strategies and spatial search task the middle plate of a series of plates with different variants of location) with hierarchical status of males and group females. Specifically thesis compares individual success pigeons in spatial tasks of varying complexity. The hardest task requires a certain level of abstraction of visual stimuli representing spatial relationships using experimentally induced two strategies: mapping strategy or specific symbol association with a position in space. The role tests on the touch screen with the help of operant conditionings. Difficulty in various stages of growing, the last stage role does manage only some individuals. Conversely easier task in real space with a bird tasked with finding the midpoint between objects in different variants locations within the arena. The difficulty of the task is not growing, and it can solve some individuals who have not learned operant conditioning if the previous job. Performance in cognitive tasks could be affected by the hierarchical status of the animal in the group. Pigeons position in the hierarchy has...

Cognitive processes associated with spatial orientation can use different reference frames: egocentric, centered on observer and allocentric, centered on objects in the environment. In this thesis, we use EEG to investigate the dynamics of brain processes accompanying spatial orientation based on these reference frames. Participants were instructed to estimate distances between objects or themselves and objects located in a virtual circular arena; this task was presented in both 2D and 3D displays. Task-related EEG changes were analyzed using a time-frequency analysis and event-related potential analysis of 128-channel EEG recordings. Through time-frequency analysis we found significant power differences in delta, theta, alpha, beta and gamma bands amongst the control, egocentric and allocentric testing conditions. We noted a decrease in alpha power in occipital and parietal regions, while a significantly stronger decrease was observed for the allocentric condition compared to both egocentric and control conditions. A similar pattern was also detectable for the beta band. We also report an increase in theta and delta power in temporal, fronto-temporal and lateral frontal regions that was significantly stronger for the egocentric condition compared to control and, in some electrodes, even...

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