Flies are highly visually guided animals. In this thesis, I have used hoverflies as a model for studying motion vision. Flies process motion vision in three visual ganglia: the lamina, the medulla, and the lobula complex. In the posterior part of lobula complex, there are around 60 lobula plate tangential cells (LPTCs). Most of LPTCs have large receptive fields where the local direction sensitivity suggests that they function as matched filters to specific types of optic flow. LPTCs connect to descending or neck motor neurons that control wing and head movements, respectively. Therefore, in this thesis I have focused on the electrophysiological responses of LPTCs to gain understanding of visual behaviors in flies. The elementary motion detector (EMD) is a model that can explain the formation of local motion sensitivity. However, responses to higher order motion, where the direction of luminance change is uncorrelated with the direction of movement, cannot be predicted by classic EMDs. Nevertheless, behavior shows that flies can see and track bars with higher order motion cues. I showed (Paper I) that several LPTCs also respond to higher order motion. Many insects, including flies, release octopamine during flight. Therefore, adding octopamine receptor agonists can mimic physical activity. Our study (Paper II) investigated the effect of octopamine on three adaptation components. We found that the contrast gain reduction showed a frequency dependent increase after octopamine stimulation. Since the contrast gain is non-directional, it is likely presynaptic to the LPTC. We therefore believe that octopamine acts on the delay filter in the EMD. In the third paper we describe a novel LPTC. The centrifugal stationary inhibited flicker excited (cSIFE) is excited by flicker and inhibited by stationary patterns. Neither of these responses can be predicted by EMD models. Therefore, we provide a new type of motion detector that can explain cSIFE’s responses (Paper III). During bar tracking, self-generated optic flow may counteract the steering effect by inducing a contradictory optomotor response. Behavior shows that during bar fixation, flies ignore background optic flow. Our study (Paper IV) focus on the different receptive fields of two LPTCs, and relate these to the bar fixation behavior. In the neuron with a small and fronto-dorsal receptive field, we find a higher correlation with bar motion than with background motion. In contrast, the neuron with a larger receptive field shows a higher correlation with background motion.

Thesis (M.S.)--Indiana University, 2003. / Includes bibliographical references (leaves 56-64). Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Thesis (M.S.)--Indiana University, 2003. / Includes bibliographical references (leaves 56-64).

Employer monitoring of communications is prevalent and on the rise due in part to the Sarbanes-Oxley Act, the Health Insurance Privacy Protection Act, and other legislation in the U.S. and other countries. However, the critical effect of this new activity on what is communicated in companies has not been assessed. This dissertation examines the impacts of computer mediated communication systems monitoring on neutral, incriminating and exculpatory content, as well as the overall volume of communications issued on monitored and non-monitored computer mediated communication systems. Incriminating communication is cataloged in a hazard communications taxonomy for this investigation. A controlled laboratory experiment has subjects participate in an instant messaging discussion on a topic for which they are likely to be aware of information that is incriminating to their organization, or its members, or both. Consistent with self awareness theory, monitored subjects engage in significantly less overall and neutral communication. They volunteer fewer high intensity hazard communications, but are less likely to curtail low intensity hazard communications. They issue denials about more incriminating topics. Contributions to research include theory development, especially in the area of standard selection; application of self-awareness theory to the new domain of computer mediated communications monitoring; a research framework; a taxonomy and coding scheme for the new hazard communications constructs; and a relative standards influence instrument and methodology for use in studying competing standards. Implications for corporate monitoring and communications policies are discussed, and a research agenda is outlined.

No description available.

In this study we sought to determine whether infants, like adults, utilize previous experience to guide figure/ground processing. After familiarization to a shape, 5-month-olds preferentially attended to the side of an ambiguous figure/ground test stimulus corresponding to that shape, suggesting that they were viewing that portion as the figure. Infants’ failure to exhibit this preference in a control condition in which both sides of the test stimulus were displayed as figures indicated that the results in the experimental condition were not due to a preference between two figure shapes. These findings demonstrate for the first time that figure/ground processing in infancy is sensitive to top-down influence. Thus, a critical aspect of figure/ground processing is functional early in life.

This study aims at explaining the significance of the &ldquo / field&rdquo / concept in contemporary architecture and urbanism, in reference to the technical definitions of the term in different disciplines. In this context, it investigates the concepts of &ldquo / field&rdquo / in physics, psychology, art theory and criticism. It highlights the reinterpretation of the &ldquo / field&rdquo / concept in physics by eminent Gestalt psychologists, and its consequences for architecture and urbanism. Starting from the definitions of the concept of &ldquo / field&rdquo / by Kurt Koffka and Kurt Lewin, and from the Gestalt Theory that constitutes the basis of these definitions, it brings into discussion a group of related notions that have been employed in art and architectural theory and criticism: &ldquo / psychophysical field,&rdquo / &ldquo / psychological life space,&rdquo / &ldquo / figure-ground,&rdquo / &ldquo / figure-field,&rdquo / and &ldquo / field-field.&rdquo

[pt] O editorial de um jornal de grande circulação faz mais do que emitir uma opinião. Ele tem poder de transformação e, muitas vezes, até mesmo de manipulação das massas de leitores. Motivada por este saber intuitivo, esta pesquisa investigou os processos psico-pragmáticos que o poderiam explicar academicamente. Adotou a Lingüística Funcional Cognitiva como abordagem teórica, mais especificamente o Modelo dos Espaços Mentais de Fauconnier (1994; 1997), assim como a Análise do Discurso (Brown e Yule, 1983). Para fazê-lo, analisou um corpus de 20 editoriais publicados nos maiores jornais do Brasil, à luz dos seguintes princípios norteadores: mesclagem, perspectivação e jogo figura-chão e elegeu as orações subordinadas como foco investigativo. Os resultados apontam que as orações subordinadas substantivas são as que mais tipicamente ocorrem no corpus assim como indicam que elas constituem espaços de referenciação nos quais crenças se colam com o espaço da realidade, projetando opiniões como se estas fossem verdades. Apesar de sintaticamente funcionarem como chão, perceptualmente são salientes e funcionam como figuras. Através da análise utilizada, a pesquisa conseguiu mostrar sistematicamente aquilo que muitos leigos apenas intuem e poderá ser ponte para práticas pedagógicas na escola de jornalismo que envolvam um processo de reflexão crítica sobre o processo cognitivo de mesclagem que ancora a produção dos editoriais. / [en] Editorials published by major newspapers project more than facts. Rather, they have the power to transform and, many times, even to manipulate readers. Inspired by common knowledge of such nature, this research aims to investigate the psycho-pragmatic facts that could explain it academically. It adopts the framework of Cognitive Linguistics, mainly Fauconnier s (1994;1997) Mental Spaces Model, as well as Discourse Analysis (Brown and Yule, 1983). To accomplish its aims, it analyzed a corpus of 20 editorials published in major Brazilian newspapers in the light of principles such as blending, figure-ground, and perspectivization and focused on subordinate clauses. Results indicate that nominal subordinate clauses are highly frequent in the genre and that they constitute a space where beliefs blend with reality as if they were one and the same. Although they function as ground syntactically, perceptually they are figure. Therefore, the research succeeded in demonstrating academically some possible psycho-pragmatic roots for the power of editorials. Programs that educate prospective journalists may benefit from its results.

I Stockholm pratades det om klubbdöden under 2019 eftersom flera högljudda kulturaktiviteter behövt stänga i innerstaden. Den huvudsakliga anledningen var konflikter mellan boende och kulturaktiviteter om bullerstörningar som naturligt uppstår när människor ska bo, verka och leva i en tät blandstadsmiljö. I Slakthusområdet ska denna problematik bemötas för att bli en nöjes- och evenemangsknutpunkt tillsammans med höga målsättningar om bostadsbyggande i blandstad. Den tidigare forskningen visar på att god ljudmiljö är mer komplext än endast reduceringen av önskade ljud utefter mätbara decibel. I Kulturkvarteren möts förståelsen av god ljudmiljö och blandstaden vid planeringen av högljudda kulturaktiviteter och utgör därför fallet i denna studie. I form av en kvalitativ innehållsanalys studerades planeringens förutsättningar, intentioner och åtgärder för att svara på om god ljudmiljö och blandstad är förenligt vid planeringen av högljudda kulturaktiviteter. För att studera det tillämpades teorin om ljud som en resurs och ljud som oönskat buller tillsammans med teorier om vad som utgör blandstaden. Dokumentstudier innefattade Slakthusområdets planprogram och Kulturkvarterens olika plandokument. Övergripande dokument från myndigheter studerades också för att skapa en större förståelse för planeringens förutsättningar. Intervjuer utförde med en planarkitekt, miljöutredare, nationell bullersamordnare, jurist och akustiker på Boverket, Naturvårdsverket, Miljöförvaltningen och Stockholms stad. Resultaten visar på att, i Kulturkvarteren, har ett defensivt förhållningssätt utgåtts ifrån där kulturaktiviteters ljudnivåer begränsas för att möjliggöra blandstadskvaliteteter. Möjliggörandet av en större variation i funktioner, människor och aktiviteter på den lilla skalan underbygger planeringens intentioner och åtgärder för en ljudmiljö där ljudkällor ska vara i balans med varandra för att inte maskera andra ljud. Bostadens riktvärden för ljud är den centrala faktorn i förutsättningarna för ljudmiljön i blandstaden och planeringens intentioner för den urbana ljudmiljön kunde därför ses som en funktion av bulleråtgärder snarare än direkta intentioner och åtgärder. Planeringen av kulturaktiviteter innebar därför inte en god ljudmiljö där högre kulturella ljud konsolideras i blandstadsmiljön utefter ljudets mening och sociokulturella kontext. Kulturkvarteren som en plats där högre kulturellt ljud görs möjligare, i högre grad, än i resten av innerstaden kunde därför ifrågasättas. Förenligheten i god ljudmiljö och blandstad vid planeringen av högljudda kulturaktivitet i Kulturkvarteren är hög i många aspekter. Högre ljudnivåer i lokaler möjliggörs och en god ljudmiljö utomhus och i bostäder säkerställs baserat på effekten på människors fysiologiska hälsa. Det förutsätter däremot en förståelse av god ljudmiljö som tystare där högre ljud, oberoende av dess subjektiva uppskattning, ska reduceras eller kontrolleras. Förenligheten i god ljudmiljö och blandstad är därför kontextuell. Högre ljudnivåer som en resurs kan innebär goda ljudkvaliteter utifrån platsens sociokulturella aspekt och ljudets mening men det är mindre förenligt med blandstaden på grund av riktvärdenas tillämpning men även planeringen intentioner för blandstadskvaliteter på den lilla skalan. Möjliggörandet av högre kulturljud i Kulturkvarteren innebar en reglering som säkerställer att riktvärden inte överstigs och inte att högre ljudnivåer möjliggörs i den urbana miljön. Jag anser därför att god ljudmiljö måste lyftas i bredare mening för att möjliggöra en större variation av ljudmiljöer som kan skapa platser i innerstaden för de kulturaktiviteter som inte ryms under riktvärdenas mätbarhet men som tillför andra goda ljudkvaliteteter. / In Stockholm, there was a discussion about the death of clubs in 2019 due to the closure of several vibrant cultural activities in the city centre. The main reason behind this was conflicts between residents and cultural activities regarding noise disturbances that naturally occur when people live, work, and coexist in a densely populated urban environment. In the Slakthusområdet area, efforts are being made to address this issue and transform it into a hub for entertainment and events, while also setting ambitious goals for mixed-use residential development. Previous research indicates that a good sound environment is more complex than simply reducing the desired sounds based on measurable decibels. In one of Slakthusområdets areas, Kulturkvarteren, the understanding of a good sound environment meets mixed-use urban development when planning for loud cultural activities, thereby making it the case of the study. Using a qualitative content analysis approach, this study examines the conditions, intentions, and measures taken in the planning process to determine whether a good sound environment and mixed-use urban development are compatible when planning for loud cultural activities. To study this, a theoretical framework consisting of sound as a resource and sound as unwanted noise was applied. This was then studied by applying theory regarding what constitutes the mixed-use city. The study involved examining documents such as the Slakthusområdet's master plan and various planning documents related to the Kulturkvarteren. Additionally, overarching documents from relevant authorities were also studied to gain a better understanding of the planning conditions. Interviews were conducted with a planning architect, environmental assessor, national noise coordinator, lawyer, and acoustician from Boverket, Naturvårdsverket, Miljöförvaltningen, and the City of Stockholm.  The findings demonstrate that, in Kulturkvarteren, a defensive approach has been taken, wherein the sound levels of cultural activities are limited to enable mixed-use qualities. Facilitating a greater variety of functions, people, and activities on a small scale supports the intentions and measures of the planning process aimed at achieving a sound environment where sound sources are balanced to avoid masking other sounds. The residential sound standards serve as a pivotal factor in shaping the acoustic conditions in the mixed-use city, and the planning intentions for the urban sound environment can therefore be viewed as a function of noise control rather than direct intentions and measures. Consequently, the planning of cultural activities does not result in a good sound environment where higher cultural sounds are integrated into the mixed-use environment based on the meaning of sound and sociocultural context. Therefore, the notion of the Kulturkvarteren as a place where higher cultural noise levels are enabled compared to the rest of the city could be subject to scrutiny. The compatibility between a good sound environment and mixed-use in the planning of loud cultural activities in Kulturkvarteren is favourable in several aspects. Higher sound levels indoors are made possible, and a favourable sound environment is ensured outdoors and in residential areas based on the impact on people's physiological well-being. However, this presupposes an understanding of a good sound environment as being quieter, where higher sounds, regardless of their subjective appreciation, should be reduced or controlled. Therefore, the compatibility between a good sound environment and mixed-use is context dependent. Higher sound levels, as a resource, may provide favourable sound qualities based on the sociocultural aspect of the location and the meaning of sound. However, it is less compatible with the mixed-use city due to the application of sound standards and the planning intentions for mixed-use qualities on a small scale. The facilitation of higher cultural sounds in the Kulturkvarteren entailed regulation to ensure that sound standards are not exceeded, rather than enabling higher sound levels in the urban environment. Hence, I argue that a broader understanding of a good sound environment is necessary to allow for a greater variety of sound environments that can create spaces in the city centre for cultural activities that fall outside the scope of measurable sound standards but contribute to other favourable sound qualities.

No description available.