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Flies use visual cues for a variety of tasks, such as maneuvering through the environment and finding potential mates. Hoverflies, in particular, have very developed eyes and use them to be able to hover mid air and perform fast, elegant movements. The Motion Vision Group, located at the Department of Neuroscience at BMC, Uppsala, studies the motion vision system of the hoverfly brain, using electrophysiology. Experiments are performed by displaying visual stimuli on a screen in front of an immobilized fly, while recording the response from a single neuron with a thin electrode.Until now, the Motion Vision group has been using the open source program VisionEgg to generate the stimuli. VisionEgg is able to display stimuli at high frame rate and has a large set of useful features such as perspective distortion. It also has a lot of drawbacks that makes it desirable to acquire new software. The main drawbacks include it being hard to learn, use and modify, as well as being unable to generate the stimuli needed for some key experiments.This master´s thesis describes the development of software more suited to the lab´s needs. This software should be able to generate some of the stimuli that were impossible to do at the moment, as well as being easy to expand and add upon. The frame rate of the displayed stimuli has to be both high and stable in order to perform high precision experiments.The resulting program is called FlyFly and has been developed iteratively in close cooperation with its end users, ensuring a user friendly end product capable of meeting the lab´s needs. FlyFly is implemented using MatLab and the Psychophysics toolbox with the graphical user interface (GUI) designed with the Guide editor. The GUI is decoupled from the functions drawing the stimuli, making it easy to improve or remove parts altogether. FlyFly is intuitive to use and allows anyone to quickly get started. It allows easy manipulation of series of trials, and supports drawing of multiple objects simultaneously. With the current machine set-up, it displays stimuli at 160 frames per second with few or no dropped frames.FlyFly is currently being used in the lab and will be so for the foreseeable future.

This investigation examined the differences in REACT, RT, and jumping performance for the countermovement jump (CMJ) versus squat jump (SJ) when beginning the movement by responding to auditory (AUD) versus visual (VIS) stimuli. The secondary purposes of this investigation are to examine gender and physical activity level differences of the aforementioned metrics and the relationship between maximal strength, REACT, and RT. Twenty-eight participants (females = 16 and males = 12) were split into three groups (low = 6, moderate = 10, and high = 12) based on their perceived physical activity levels in accordance with ACSM physical activity requirements. Over the course of two days, participants completed an isometric midthigh pull (IMTP), CMJs, and SJs on force plates. Participants jumped as fast as possible upon receiving either an AUD or VIS stimulus in randomized order and without awareness of the stimulus type. Additionally, participants completed maximum voluntary isometric contractions (MVIC) for the tibialis anterior (TA), medial head of the gastrocnemius (GM), rectus femoris, and biceps femoris (BF) of the right leg using Electromyography (EMG) on day two. Participants then completed the CMJ and SJ protocols from day one. The findings revealed that participants displayed significantly faster reaction times (RT) to VIS stimuli than AUD stimuli. Furthermore, RT was faster during the CMJ. The low physical activity group showed faster reaction times during the CMJ. However, no significant differences were observed for the CMJ metric. Significant variations in muscle EMG root mean square (RMS) and mean power frequency (MPF) values were found for both AUD and VIS stimuli during the CMJ phases. Peak propulsive power and jump height (JH) significantly differed during the AUD stimulus for the SJ, while muscle strength did not show a significant correlation with either stimulus. This study highlights the influence of stimulus type and physical activity levels during quick reactions and explosive movements. Training methods and practice tactics may benefit from including visual cues to enhance performance, especially for athletes in sports where rapid visual processing and reaction are critical.

Este trabalho dedica-se à comparação de quatro tipos distintos de cemitério (Clássico, Jardim, Galeria e Contemporâneo) sob o enfoque da visitação, experiência e percepção de seus espaços. Para tanto, foi proposto um método de análise pelo qual se computam atributos capazes de desencadear diferentes percepções e emoções nos visitantes que os experienciam. Tal método baseou-se nas possibilidades de ações disponíveis nos espaços e nos estímulos ofertados aos visitantes que os percorrem na situação de visita, apoiando-se em análises da configuração do espaço físico e análises de simulações de percursos em cada um dos exemplos estudados. Os resultados obtidos pelo método derivam da comparação dos quatro tipos utilizando um modelo de sintaxe da forma e um modelo de percepção da forma para computar estímulos espaciais e visuais encontrados ao longo dos percursos. O resultado da análise demonstra que, em alguns aspectos, existe relativa similaridade entre os quatro tipos e,sob outros aspectos, notório contraste. O tipo contemporâneo caracteriza-se pelo maior número de aspectos distintivos ou singulares. / This work is dedicated to research, analyses and comparison of four different types of cemeteries under the focus of visit, experience and perception of such spaces, emphasizing the contemporary cemetery model. The method of analysis focuses on the attributes offered by the cemeteries and the different emotions and perceptions they cause on the visitors. This method was based on the available possibilities of action on the space and the stimulus information offered to the visitors, relying on global syntactic analysis of the samples and local space-visual analysis of predetermined paths in each of the samples analyzed. The obtained results come from the comparison of the different types of cemeteries based on the global syntactic calculation and the calculation of the spatial and visual stimulus found along the paths. The results demonstrate, in some aspects, similarity among the types and in other aspects contrast. But, ultimately, ensure distinction of the contemporary type of cemetery among the others.

Este trabalho dedica-se à comparação de quatro tipos distintos de cemitério (Clássico, Jardim, Galeria e Contemporâneo) sob o enfoque da visitação, experiência e percepção de seus espaços. Para tanto, foi proposto um método de análise pelo qual se computam atributos capazes de desencadear diferentes percepções e emoções nos visitantes que os experienciam. Tal método baseou-se nas possibilidades de ações disponíveis nos espaços e nos estímulos ofertados aos visitantes que os percorrem na situação de visita, apoiando-se em análises da configuração do espaço físico e análises de simulações de percursos em cada um dos exemplos estudados. Os resultados obtidos pelo método derivam da comparação dos quatro tipos utilizando um modelo de sintaxe da forma e um modelo de percepção da forma para computar estímulos espaciais e visuais encontrados ao longo dos percursos. O resultado da análise demonstra que, em alguns aspectos, existe relativa similaridade entre os quatro tipos e,sob outros aspectos, notório contraste. O tipo contemporâneo caracteriza-se pelo maior número de aspectos distintivos ou singulares. / This work is dedicated to research, analyses and comparison of four different types of cemeteries under the focus of visit, experience and perception of such spaces, emphasizing the contemporary cemetery model. The method of analysis focuses on the attributes offered by the cemeteries and the different emotions and perceptions they cause on the visitors. This method was based on the available possibilities of action on the space and the stimulus information offered to the visitors, relying on global syntactic analysis of the samples and local space-visual analysis of predetermined paths in each of the samples analyzed. The obtained results come from the comparison of the different types of cemeteries based on the global syntactic calculation and the calculation of the spatial and visual stimulus found along the paths. The results demonstrate, in some aspects, similarity among the types and in other aspects contrast. But, ultimately, ensure distinction of the contemporary type of cemetery among the others.

Este trabalho dedica-se à comparação de quatro tipos distintos de cemitério (Clássico, Jardim, Galeria e Contemporâneo) sob o enfoque da visitação, experiência e percepção de seus espaços. Para tanto, foi proposto um método de análise pelo qual se computam atributos capazes de desencadear diferentes percepções e emoções nos visitantes que os experienciam. Tal método baseou-se nas possibilidades de ações disponíveis nos espaços e nos estímulos ofertados aos visitantes que os percorrem na situação de visita, apoiando-se em análises da configuração do espaço físico e análises de simulações de percursos em cada um dos exemplos estudados. Os resultados obtidos pelo método derivam da comparação dos quatro tipos utilizando um modelo de sintaxe da forma e um modelo de percepção da forma para computar estímulos espaciais e visuais encontrados ao longo dos percursos. O resultado da análise demonstra que, em alguns aspectos, existe relativa similaridade entre os quatro tipos e,sob outros aspectos, notório contraste. O tipo contemporâneo caracteriza-se pelo maior número de aspectos distintivos ou singulares. / This work is dedicated to research, analyses and comparison of four different types of cemeteries under the focus of visit, experience and perception of such spaces, emphasizing the contemporary cemetery model. The method of analysis focuses on the attributes offered by the cemeteries and the different emotions and perceptions they cause on the visitors. This method was based on the available possibilities of action on the space and the stimulus information offered to the visitors, relying on global syntactic analysis of the samples and local space-visual analysis of predetermined paths in each of the samples analyzed. The obtained results come from the comparison of the different types of cemeteries based on the global syntactic calculation and the calculation of the spatial and visual stimulus found along the paths. The results demonstrate, in some aspects, similarity among the types and in other aspects contrast. But, ultimately, ensure distinction of the contemporary type of cemetery among the others.

Este trabalho descreve as pesquisas e desenvolvimentos em instrumentação eletrônica computacional, realizados para viabilizar experiências na área de neurobiofísica, tendo como objetivos principais a geração de estímulos visuais para invertebrados e a captação de sinais eletrofisiológicos gerados por sistemas biológicos sensoriais submetidos a estímulos. Trata-se de um conjunto de equipamentos que, operando de maneira integrada, são capazes de fornecer e sincronizar estímulos, realizar a aquisição dos dados de sinais neurais a serem utilizados para controle e análise em experiências in vivo\" nos estudos da visão de invertebrados no Laboratório de Neurobiofísica - DipteraLab do IFSC. A integração desta instrumentação eletrônica visa facilitar a sua utilização durante os experimentos, permitindo o acompanhamento das aquisições de dados neurais, viabilizando a realização de experimentos com alterações dos estímulos através de realimentação em tempo real. / This work describes the research and development of computational instrumentation to be used in experimental neurobiophysics. The developed electronic modules operate in an integrated manner and are used to generate visual stimuli for invertebrates and capture electrophysiological signals generated by biological systems subjected to sensory stimuli. They are able to provide synchronized stimuli and perform data acquisition of neural signals events to be used for control and analysis of vision experiments with invertebrates at the Laboratory of Neurobiophysics Dipteralab Laboratory, at the IFSC. The integration of electronic instrumentation facilitate its use during experiments allowing, through its monitoring capabilities of the neural data acquisition, the realization of experiments with real time stimuli changes through feedback. The possibility to perform pre-analyses of neural responses in behavioral closed loop experiments is also implemented.

Este trabalho descreve as pesquisas e desenvolvimentos em instrumentação eletrônica computacional, realizados para viabilizar experiências na área de neurobiofísica, tendo como objetivos principais a geração de estímulos visuais para invertebrados e a captação de sinais eletrofisiológicos gerados por sistemas biológicos sensoriais submetidos a estímulos. Trata-se de um conjunto de equipamentos que, operando de maneira integrada, são capazes de fornecer e sincronizar estímulos, realizar a aquisição dos dados de sinais neurais a serem utilizados para controle e análise em experiências in vivo\" nos estudos da visão de invertebrados no Laboratório de Neurobiofísica - DipteraLab do IFSC. A integração desta instrumentação eletrônica visa facilitar a sua utilização durante os experimentos, permitindo o acompanhamento das aquisições de dados neurais, viabilizando a realização de experimentos com alterações dos estímulos através de realimentação em tempo real. / This work describes the research and development of computational instrumentation to be used in experimental neurobiophysics. The developed electronic modules operate in an integrated manner and are used to generate visual stimuli for invertebrates and capture electrophysiological signals generated by biological systems subjected to sensory stimuli. They are able to provide synchronized stimuli and perform data acquisition of neural signals events to be used for control and analysis of vision experiments with invertebrates at the Laboratory of Neurobiophysics Dipteralab Laboratory, at the IFSC. The integration of electronic instrumentation facilitate its use during experiments allowing, through its monitoring capabilities of the neural data acquisition, the realization of experiments with real time stimuli changes through feedback. The possibility to perform pre-analyses of neural responses in behavioral closed loop experiments is also implemented.

A standard Neurofeedback approach to mitigate the working memory decline in some fragile groups (elderly, subjects affected by stroke or Alzheimer's disease) can be suboptimal for some patients. The goal of this research is to investigate which visual stimulus (among colour, geometrical shape, direction, and symbol) is the most suited for each of the six healthy participants and which brain areas are the most discriminative, during the maintenance of a presented stimulus in a retro-cue-based working memory experiment. In order to identify the most discriminative stimulus, the single-trial classification accuracies of some Support Vector Machines, trained on the theta, alpha and beta electroencephalography power bands, have been compared; while, in order to identify the most involved brain regions, three machine learning feature reduction techniques have been explored: the first based on a massive univariate analysis, the second based on multivariate filtering and wrapping, and the last one based on Frequency-based Common Spatial Pattern. The results have shown that the univariate approach, more than the others, managed to clearly identify for each participant at least one preferential type of stimulus and a brain region of discriminative electrodes during the maintenance of the stimulus. These promising results can be interpreted as a further step to optimize the Neurofeedback working memory enhancement through a personalised approach.

No / Auditory signals have been shown to exert a marked influence on visual perception in a wide range of tasks. However, the mechanisms of these interactions are, at present, poorly understood. Here we present a series of experiments where a temporal cue within the auditory domain can significantly affect the localisation of a moving visual target. To investigate the mechanism of this interaction, we first modulated the spatial positional uncertainty of the visual target by varying its size. When visual positional uncertainty was low (small target size), auditory signals had little or no influence on perceived visual location. However, with increasing visual uncertainty (larger target sizes), auditory signals exerted a significantly greater influence on perceived visual location. We then altered the temporal profile of the auditory signal by modulating the spread of its Gaussian temporal envelope. Introducing this temporal uncertainty to the auditory signal greatly reduced its effect on visual localisation judgements. These findings support the view that the relative uncertainty in individual sensory domains governs the perceptual outcome of multisensory integration.