Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vi, 53 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 50-51).

The moments that follow a perceptual decision can be as critical as the ones leading up to it. This thesis examines rapid olfactory decisions in mice and rapid changes of mind following an initial decision in humans. To study olfactory decisions, we trained mice to discriminate different odor concentrations in a novel head-fixed paradigm. Odor concentration is an important cue for localizing odor sources, from searching for food and mates to avoiding predators. However, little is known about how olfactory systems encode odor concentration. We found that mice could discriminate the different odor concentrations in as little as 80 ms after odorant inhalation. This is an unprecedented speed for olfaction and is fast even by the standards of other sensory modalities. We attribute this new insight into olfactory perception to our choice of motor output, accurate sniff measurement, and precise stimulus control. This result suggests that odor-based decisions can be very rapid and based on information over a very brief temporal window. To study changes of mind following an initial decision, humans made decisions about a noisy visual stimulus, which they indicated by moving a handle. Although they received no additional information after initiating their movement, their hand trajectories betrayed a change of mind on some trials. We modeled these changes of mind by extending the diffusion-to-bound model, originally developed to account for both the timing and accuracy of the initial decision. We propose that noisy evidence is accumulated over time until it reaches a criterion, or bound which determines the initial decision, and that the brain exploits information that is in the processing pipeline when the initial decision is made to subsequently either reverse or reaffirm the initial decision. Sensory and motor processing latencies ensure that not all of the information available from stimulus onset to movement initiation contributes to the initial decision. This model explains both the frequency of changes of mind, as well as their dependence on both task difficulty and whether the initial decision was accurate or erroneous.

Olfactory perception is as sociocultural a phenomenon as it is a physiological one. Scents of all types and the meanings assigned to them contribute to and shape human cultures, and humans have deliberately manipulated smells to sway the opinions and value judgements of others since, at the very least, the dawn of agriculture. ‘Smellscapes’ define our environments. How we smell what we smell and why we interpret what we smell the way we do are inextricably intertwined, and this was no less true in the Classical world. When we study how people in antiquity examined the sense of smell in general and the corresponding roles of perfume in particular, we see many of the same issues and questions being raised as concern scientists today. Applying modern models to ancient practices can enhance insight into Greek and Roman cultures. This paper will discuss physiological olfactory perception as the authors in the Classical and Hellenistic periods defined and described that, and will examine the primary literature regarding perfume in order to provide a specific example of one way in which we can be initiated into the mysteries of a different and long-gone cultural sensorium through the written word.

The dominance of sight in built environmental design and management is well documented with smell overlooked by built environment professionals, considered of primarily negative influence upon experience and perception. However odour has special characteristics, retained in memory longer than visual images, and can transport people back through space and time through recollection and association. As a result, it has an important role to play in urban place experience. Few dedicated studies have examined the role of smell in environmental experience and perception. As a result, important questions are raised: What odours are commonplace in contemporary urban environments? How are they perceived? What is the relationship between odour and place perception and experience? What tools are available when designing olfactory environments? What are the ethical implications when doing so? Drawing on evidence from smellwalks and semi-structured interviews with fifty-two professionals, licensees, community representatives and business people in Doncaster, accompanied by data involving eighty-two residents, collected in Manchester, Sheffield and Clerkenwell, London by the Vivacity2020 Project, smell is argued highly influential in place experience and perception. This empirical study is one of the first to evidence odour perception as related to place perception with individuals playing an active role in perception according to past experiences and olfactory perceptual state. A potentially positive role for odour is identified in restorative experiences of the city, gained from natural and non-natural sources. A range of tools are introduced, assisting in designing with odour without reliance upon scenting practices, themselves identified problematic due to perceived physical and psychological reactions. Through adopting a pragmatic approach to findings, where experiences of odour are considered on a site by site basis and within the context of local stakeholder engagement, a new model is proposed by which olfactory design can be incorporated into everyday urban design decision making processes.

There are some discrepancies in the literature regarding the response of the "induced waves" of the olfactory bulb to odorous stimuli. This work was designed to resolve the controversy by relating the different types of response to alertness of the animal and to concentration of the odour. The envelope of 40 Hz activity from the olfactory bulbs of unanaesthetised cats was recorded on a polygraph, and found to vary with respiration. The animal's nose projected into a stream of clean air to which odorant could be added at different fixed rates for about a minute at intervals. The amplitude of induced wave activity during the stimulus was compared to that shortly before it. Odour concentrations were varied within a 5 x 10⁶ -fold range and the logarithm taken. The alertness of the cat was estimated on a 5-point scale. The data for the middle alertness category were eliminated and those of the two extreme groups subjected to statistical analysis by multiple regression. The percentage change in integrated induced wave activity during stimulus as compared to that during control in a drowsy cat was found to be independent of stimulus concentration and could be in either direction but usually increased. In an aroused cat regression to a third order polynomial was statistically significant (p < 0.02) and accounted for 0.34 of the variability. This result appears surprisingly good in view of the enormous spontaneous variation in the signal and the unreliability of the stimulus, both as to its exact concentration and in the resemblance of its presentation parameters to a square wave. It would be worth while to repeat this study with more animals, more odours and a. better olfactometer design. The shape of the regression was predicted as follows. At low concentrations an alert cat would show an olfactory response in the form of a depression of induced waves. At intermediate concentrations an alarm response would sometimes increase alertness, augmenting the induced waves. At high concentrations the trigeminal-to-autonomic noxious vapour response would intervene, mechanically reducing access of air to olfactory receptors and/ or respiration. A drowsy cat on the other hand might be subject to alerting by any suprathreshold concentration, or could ignore the stimulus with or without perceiving it. Effects of non-olfactory stimuli and spontaneous variations were in fact far more obvious than most of the "olfactory responses". / Medicine, Faculty of / Cellular and Physiological Sciences, Department of / Graduate

Software architecture (SA) smells are design problems in the internal structure and behavior of an SA. These can be seen as a specific category under the umbrella concept of technical debt (TD). TD is a central concept in software development projects and having the means to detect and measure the smells is essential to understand impairments they may cause. However, TD is only limited to the technical aspects and does not describe smells found on an enterprise level. Enterprise architecture debt (EAD) expands the concepts of TD beyond the technical aspects such that it covers the debts that can be found in all layers of an Enterprise Architecture (EA). EA smells give a measurement for EAD by providing means for identifying and detecting the smell, hence enabling a method to quantify the level of debt. The goal of this thesis is to find EA smells derived from existing SA smells. In total, three new EA smells were presented based on existing SA smells. Each new smell was described by a short description that informally summarizes the smell. This was followed by an indication of the smell’s origin and reasoning about the effects on the quality. Then, an illustrative example of the smell was provided. Finally, a detection algorithm was also provided and implemented in a prototype detection program. This thesis serves as a basis for measurements of the quality of an EA and motivation for future research in this area. It is argued that the finding of EA smells can facilitate quality assessment in an EA. / Mjukvaruarkitektursrötor (MA-rötor) är designproblem i den interna strukturen och beteende i en mjukvaruarkitektur. Dessa kan ses som en specifik kategori under samlingsbegreppet teknisk skuld (TS). TS är ett centralt begrepp inom projekt i mjukvaruutveckling och att ha en metod att upptäcka och mäta dessa rötor är viktigt för att förstå försämringar dessa kan orsaka. TS är dock enbart avgränsat till de tekniska aspekterna och beskriver inte rötorna som kan finnas på en verksamhetsnivå. Verksamhetsarkitektursskulder (VAS) expanderar konceptet av TS utöver de tekniska aspekterna så att de även täcker skulderna som kan finnas på alla nivåer i en verksamhetsarkitektur (VA). VA-rötor ger ett mätvärde för VAS, genom att förse ett sätt att upptäcka rötorna och därmed möjliggöra ett sätt att kvantifiera graden av skuld. Målet i denna avhandling är att hitta VA-rötor som är härledda från befintliga MA-rötor. Totalt har tre nya VA-rötor presenterats baserat på befintliga MA-röter. Varje ny röta har beskrivits med en kort beskrivning som informellt summerar rötan. Detta följt av en indikation av rötans ursprung och resonemang om dess effekt på kvalitén. Ett illustrativt exempel har även presenterats. Slutligen, har en algoritm för att upptäcka rötan också presenterats och implementerats i ett prototypprogram för att upptäcka rötan. Denna avhandling används som en grund för mätvärden av kvalité i en VA och motivation för framtida studier i detta område. Det argumenteras för att identifieringen av VA-rötor kan förenkla kvalitetsbedömningen av en VA.

Thesis (Ph.D.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 174-202.

This project aims to find how, why and by which means the sense of smell can create meaningful interactions in the field of escape rooms, by taking a main role in the interactions that occur in said games, by adding an additional layer of complexity and embodiment. The project finished with the finding that it is not only possible to create meaningful interactions and expand on the possibilities of smell interaction, but also by encouraging future exploration and discussion of the sense of smell as an interactive medium and material.

This project explores opportunities in designing hybrid digital/physical smell rehabilitation video games using no unique game peripherals. During a 13-week process, three major iterations were created and externally tested on a small user group. The first two iterations contained five simple minigames that served to explore different types of game concepts. For the final iteration, two minigames were fully developed, a slow- and fast-paced game. The main findings were that slow-paced better-facilitated smell training than fast-paced games; aesthetics increased the player’s focus on small training; not utilising unique game peripherals limited the design opportunities and implementation of smell mechanics.

The primary aim of this thesis was to investigate, using functional magnetic resonance imaging (fMRI), the neurophysiological basis of multisensory integration involving smell and vision. To achieve this goal, several technical challenges had to be addressed: the attainment of sufficiently high quality fMRI images in olfactory brain regions within the orbitofrontal cortex (OFC), the construction of a stimulus delivery system adequate for rapid and controlled odour delivery in the MRI environment, and optimal strategies for delivering and perceiving liquid flavour stimuli in the scanner. In two initial fMRI experiments, strategies including sensitivity encoding and passive shimming to improve OFC image quality were explored. The results demonstrated that both methods can improve signal detection in OFC, a brain area particularly sensitive to susceptibility artefacts. In a further fMRI study, the effectiveness of two methods of delivering odorants dissolved in liquids was compared. In this study, the same set of participants was required to either swallow the liquid immediately after delivery or hold it in their mouths for a brief period of time. The results indicated that while both methods allowed detection of activity in primary olfactory and gustatory cortices, activation of the OFC was not observed when participants swallowed the liquids immediately. This was presumed to be due to the increased head motion associated with swallowing. Finally, the mechanisms underlying visual-olfactory integration were investigated using a combination of behavioural and imaging methods. An initial behavioural study revealed strong colour-odour associations for certain smells associated with fruits (e.g. lemon - yellow). In a subsequent fMRI study, volunteers were presented with a selection of the most colour-associated odours from the prior behavioural study either in isolation or in the presence of congruent and incongruent colours. Analysis of the fMRI data revealed that a highly left lateralised network of brain areas comprising of the OFC and insular showed increasingly stronger responses to odour-colour combinations of higher congruency. In a follow-up fMRI study, this same network was also found to be responsible for integrating odours, not only with colours, but also with their corresponding visual images (objects). In sum, the series of fMRI studies undertaken in this thesis argue for a fundamental role of the OFC in the integration of olfactory-visual inputs in the human brain.