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Entrainment is the rhythmic coordination of movement with a signal or other person. Most studies on entrainment have looked at synchronization with auditory or visual signals, whereas much less is known about how entrainment emerges mutually between individuals, especially when they are in physical contact with one another. In this dissertation, I empirically explored dance partnering as an ecological model for understanding interpersonal entrainment through haptic interaction. I began by performing a statistical meta-analysis of functional neuroimaging articles devoted to the most common experimental paradigm for entrainment, namely externally-paced finger tapping to an acoustic rhythmic stimulus (Chapter 2). The results showed that the cerebellar vermis was a strong neural marker of entrainment, as it was more activated by externally-paced tapping than by self-paced tapping, whereas the basal ganglia was activated by both types of rhythmic movements. Next, I used functional magnetic resonance imaging (fMRI) with a group of participants trained at couple dancing in order to explore the neural basis of haptic mutual entrainment, with a focus on the dynamics of leading and following (Chapter 3). While mutual interaction overall engaged brain networks involved in somatosensation, internal-body sensation and social cognition, leading showed enhanced activity principally in areas for motor control and self-initiated action, whereas following showed enhanced activity mainly in sensory and social-cognition areas. Finally, I used 3D motion capture to explore multisensory coupling for mutual entrainment at the group level during folk dancing (Chapter 4). The results showed that dancers relied most extensively on haptic coupling to synchronize as a group, whereas auditory and visual coupling were dependent on the spatiotemporal context. These studies advance our understanding of the neural and behavioural mechanisms underlying joint actions in which entrainment emerges mutually through haptic interaction. / Thesis / Doctor of Philosophy (PhD) / Entrainment is the rhythmic coordination of movement with a signal or other person. Most studies on entrainment have looked at synchronization with auditory or visual signals, whereas much less is known about how entrainment emerges mutually between individuals, especially when they are in physical contact with one another. I began my research by performing a statistical analysis of the literature examining the brain basis of synchronization with auditory signals, identifying a key brain area for entrainment. Next, using a group of participants trained at couple dancing, I explored the brain areas engaged when two individuals in physical contact improvised movement together, focusing on who is leading or following the interaction. Finally, I explored how folk dancers use multiple sensory signals (auditory, visual and tactile) to synchronize as a group. These studies advance our understanding of the neural and behavioural mechanisms by which people mutually entrain through physical interaction.

Increasing demands, shrinking financial and human resources, and increased infrastructure deterioration have made the task of maintaining the infrastructure systems more challenging than ever before. Life-cycle cost analysis (LCCA) is an important tool for transportation infrastructure management, which is used extensively to support project level decisions, and is increasingly being applied to enhance network level analysis. However, traditional LCCA tools cannot practically and effectively utilize expert knowledge and handle ambiguous uncertainties. The main objective of this dissertation was to develop enhanced LCCA models using soft computing (mainly fuzzy logic) techniques. The proposed models use available "real-world" information to forecast life-cycle costs of competing maintenance and rehabilitation strategies and support infrastructure management decisions. A critical review of available soft computing techniques and their applications in infrastructure management suggested that these techniques provide appealing alternatives for supporting many of the infrastructure management functions. In particular, LCCA often utilizes information that is uncertain, ambiguous and incomplete, which is obtained from both existing databases and expert opinion. Consequently, fuzzy logic techniques were selected to enhance life-cycle cost analysis of transportation infrastructure investments because they provide a formal approach for the effective treatment of these types of information. The dissertation first proposes a fuzzy-logic-based decision-support model, whose inference rules can be customized according to agency's management policies and expert opinion. The feasibility and practicality of the proposed model is illustrated by its implementation in a life-cycle cost analysis algorithm for comparing and selecting pavement maintenance, rehabilitation and reconstruction (MR&R) policies. To enhance the traditional probabilistic LCCA model, the fuzzy-logic-based model is then incorporated into the risk analysis process. A fuzzy logic approach for determining the timing of pavement MR&R treatments in a probabilistic LCCA model for selecting pavement MR&R strategies is proposed. The proposed approach uses performance curves and fuzzy-logic triggering models to determine the most effective timing of pavement MR&R activities. The application of the approach in a case study demonstrates that the fuzzy-logic-based risk analysis model for LCCA can effectively produce results that are at least comparable to those of the benchmark methods while effectively considering some of the ambiguous uncertainty inherent to the process. Finally, the research establishes a systematic method to calibrate the fuzzy-logic based rehabilitation decision model using real cases extracted from the Long Term Pavement Performance (LTPP) database. By reinterpreting the model in the form of a neuro-fuzzy system, the calibration algorithm takes advantage of the learning capabilities of artificial neural networks for tuning the fuzzy membership functions and rules. The practicality of the method is demonstrated by successfully tuning the treatment selection model to distinguish between rehabilitation (light overlay) and do-nothing cases. / Ph. D.

Individuals that are diagnosed with a neurodiverse condition (including, among other things, ADHD, autism, dyslexia, and Tourette syndrome) are not feeling included in organizations in today’s society. The feeling of not being included stems from experiencing discrimination, from bullying and harassment, and not given the same opportunities regarding succeeding at work. The discrimination experienced by neurodiverse individuals in work environments is partly a result of the managers' limited knowledge about the various neurodiverse conditions and how to include them in organizations. In Sweden between 10-15% have a neurodiverse condition, 3% of adults have ADHD, 1-2% have autism, 0,5% have Tourette’s syndrome and 5-8% have dyslexia which indicates that the problem with including neurodiverse individuals is affecting a portion of the population as well as the organizations themselves. This study’s purpose is to examine what managers’ ideas are about how to promote inclusion for neurodivergent employees in Swedish organizations. To conduct this research a literature review was carried out to gather knowledge about neurodiversity and the conditions the term entails, inclusion and the problems of employment for individuals with neurodiversity and it guided the research to a gap in previously written studies. An interview guide was created to use during the semi-structured interviews, a total of five interviews were performed both through online video chats and in person to gather relevant, in-depth information to answer the research question. The results indicated that managers are on the right track in progressing towards promoting inclusion of neurodivergent individuals during the stages of attracting, orientation and familiarization, and in training. However, the interviews also indicated that managers could devote more efforts in adapting towards neurodivergent individuals in the stages of recruitment process, performance tracking, progression plans, and in evaluating processes. Interestingly, as seen in the findings regarding the stages of creating awareness and keeping employees, the managers understand the importance of educating themselves and other employees regarding neurodiversity within their organization. Although, the overall findings indicates that their knowledge regarding neurodiversity is insufficient, even though they are advocating for the significance of including neurodivergent individuals in organizations. A possible reason for the lacking adjustment in inclusion practices towards neurodivergent individuals is that organizations need further resources in terms of human resources as well as the economic aspects of it. Finally, the study shows that the majority of the managers had not reflected anything regarding potentially negative outcomes from the signals that inclusion practices can produce and be perceived by other employees within the organization, which can be crucial in understanding how to successfully implement inclusion practices for neurodivergent individuals

No / In this paper we propose a unified approach for integrating implicit and explicit knowledge in neurosymbolic systems as a combination of neural and neuro-fuzzy modules. In the developed hybrid system, training data set is used for building neuro-fuzzy modules, and represents implicit domain knowledge. The explicit domain knowledge on the other hand is represented by fuzzy rules, which are directly mapped into equivalent neural structures. The aim of this approach is to improve the abilities of modular neural structures, which are based on incomplete learning data sets, since the knowledge acquired from human experts is taken into account for adapting the general neural architecture. Three methods to combine the explicit and implicit knowledge modules are proposed. The techniques used to extract fuzzy rules from neural implicit knowledge modules are described. These techniques improve the structure and the behavior of the entire system. The proposed methodology has been applied in the field of air quality prediction with very encouraging results. These experiments show that the method is worth further investigation.

When adults with neurological conditions can access occupational therapy (OT) services, they have better outcomes. Unfortunately, many people who are living in the community with these conditions do not participate in OT services. This can compound deficits, lead to re-hospitalization, and negatively impact independence and quality of life. The issues with access for this population, specifically adults aged 18-65, can largely be attributed to lack of awareness of the role and scope of OT, lack of availability of specialized services, and issues with affordability. Evolve Occupational Therapy (Evolve OT) is a program designed specifically for this group, adults with neurological conditions aged 18-65 who have difficulty accessing OT services. This innovative approach to service delivery provides an alternative access pathway, treatment, and payment models that are intentionally designed to increase participation in and utilization of OT services. With this program, it is expected that patients will report increased satisfaction with participation, increased quality of life, and outcomes will hopefully effect change amongst policymakers.

Au cœur de la cognition, du comportement et des émotions, le cerveau demeure un organe encore méconnu. L'une des approches les plus novatrices utilisées pour son exploration est l'imagerie calcique, qui offre la possibilité de suivre en temps réel l'activité neuronale. Initialement pratiquée sur des animaux immobilisés, la miniaturisation des composants optiques et des capteurs d'images a permis le développement de nouveaux outils, appelés mini-endoscopes ou microendoscopes, permettant désormais ce type d'études sur des animaux libres de se déplacer. Les mini-endoscopes possédant des résolutions cellulaires (3 µm à 15 µm), ils présentent des limites quant à l'observation de structures plus fines telles que les dendrites et les épines dendritiques (∼ 0.4 µm). Dans cette thèse, après avoir présenté un nouveau design d'endoscope fonctionnant à deux couleurs, nous exposons trois solutions novatrices visant à améliorer la résolution des mini-endoscopes. La première implique l'intégration d'une lentille à cristaux liquides ajustable, connue sous le nom de lentille fovéale. Cette lentille permet de modifier localement la distance focale lorsqu'elle est positionnée dans la voie d'imagerie. Nous avons obtenu un ajustement allant jusque 244 µm. Nous démontrons également la génération de spots lumineux dans le champ de vue en utilisant une seconde lentille fovéale placée dans la voie d'excitation. La seconde solution vise à corriger les aberrations optiques présentes dans le système microendoscopique, en particulier celles introduites par les lentilles à gradient d'indice. Pour ce faire, nous utilisons une lentille ajustable à base de cristaux liquides dont l'électrode circulaire est segmentée en huit électrodes indépendantes, permettant de remodeler la forme du front d'onde optique en introduisant des retards de phase. Nous faisons la caractérisation complète de cette lentille et faisons la démonstration de son efficacité en générant des fronts d'ondes aléatoires. La troisième solution repose sur l'utilisation de techniques de super-résolution pour surpasser la limite de diffraction. À cette fin, nous avons développé un module à base de cristaux liquides permettant de générer les différents motifs d'illumination nécessaires à l'application de la technique de l'illumination structurée. / At the core of cognition, behavior, and emotions, the brain remains a largely undiscovered organ. One of the most innovative approaches used for its exploration is calcium imaging, providing the ability to monitor neuronal activity in real time. Initially conducted on immobilized animals, the miniaturization of optical components and image sensors has led to the development of new tools, known as mini-endoscopes or microendoscopes, enabling such studies on freely moving animals. While mini-endoscopes have cellular resolutions (3 µm to 15 µm), they have limitations in observing finer structures such as dendrites and dendritic spines (∼ 0.4 µm). In this thesis, after introducing a new two-color endoscope design, we present three innovative solutions aimed at improving mini-endoscope resolution. The first involves integrating an adjustable liquid crystal lens, known as a foveal lens, to locally modify the focal distance when positioned in the imaging path. We achieved adjustments up to 244 µm. We also demonstrate the generation of bright spots in the field of view using a second foveal lens placed in the excitation path. The second solution aims to correct optical aberrations in the microendoscopic system, especially those introduced by gradient index lenses. To achieve this, we use an adjustable liquid crystal lens with a circular electrode segmented into eight independent electrodes, allowing the reshaping of the optical wavefront by introducing phase delays. We conduct a comprehensive characterization of this lens and demonstrate its effectiveness by generating random wavefronts. The third solution relies on the use of super-resolution techniques to overcome the diffraction limit. For this purpose, we developed a liquid crystal-based module to generate various illumination patterns necessary for the application of structured illumination techniques.

Titre de l'écran-titre (visionné le 6 novembre 2023) / Ce présent projet de maîtrise porte sur l'étude du couplage neurovasculaire, soit la relation entre l'activité neuronale et la dilatation/constriction des vaisseaux sanguins, car une dysfonction dans le couplage neurovasculaire est une des caractéristiques de certaines pathologies cérébrales telles que la maladie d'Alzheimer, l'hypertension intracrânienne et l'AVC ischémique, mais aucune technique d'imagerie existe pour mesurer l'activité neuronale et l'oxygénation vasculaire cérébrale simultanément et indépendamment. Ce projet de recherche a pour buts principaux de développer un modèle animal de souris et un protocole d'imagerie pour étudier le couplage neurovasculaire in vivo injectées d'un adénovirus associé (AAV) à l'aide d'un microscope 2-photons. Cette modalité d'imagerie, permet d'exciter et d'imager des structures fluorescentes à haute résolution spatiale. Cette méthode de microscopie a l'avantage de produire des images contenant l'information venant uniquement du plan focal, et de permettre une plus grande profondeur de pénétration par rapport aux autres techniques de microscopie standards. Dans ce projet, un modèle animal a été développé et optimisé pour exprimer la protéine fluorescente GCaMP6s dans le corps cellulaire des neurones excitateurs et inhibiteurs chez des souris adultes. Ce modèle animal exprime aussi le fluorophore Texas Red qui est un marqueur de plasma sanguin. Les paramètres du microscope 2-photons ont été déterminés pour imager et mesurer l'activité neuronale ainsi que pour imager la vasculature cérébrale simultanément et indépendamment dans le cortex somatosensoriel qui est relié aux mouvements des moustaches. Les mesures acquises démontrent que cette technique d'imagerie et ce modèle animal permettent d'obtenir de l'information sur l'activité neuronale avec et sans stimulation sur des souris anesthésiées ou éveillées. Les stimulations externes appliquées à la souris imagée sont des bouffées d'air envoyées sur les moustaches d'un côté du museau de la souris. Des images de la structure vasculaire ont été obtenues avec le faisceau gaussien du microscope 2-photons, mais aussi avec le faisceau de Bessel qui permet d'acquérir des images volumiques. L'étude du couplage neurovasculaire de ce modèle animal a été faite au microscope 2-photons en corrélant l'intensité des signaux émis par GCaMP6s et par Texas Red. De plus, la microscopie à champ large a été exploitée pour quantifier l'hémodynamique dans l'ensemble du cortex, puis ainsi vérifier la corrélation entre l'oxygénation du sang et l'activité neuronale. Finalement, la possibilité de mesurer le débit sanguin au microscope 2-photons et de détecter l'activité neuronale au microscope à champ large a été évaluée. / This present master's project focuses on the study of neurovascular coupling, i.e. the relationship between neuronal activity and the dilation/constriction of blood vessels, because a dysfunction in neurovascular coupling is one of the characteristics of certain cerebral pathologies like Alzheimer's disease, intracranial hypertension and ischemic stroke, but no imaging technique exists to measure neuronal activity and cerebral vascular oxygenation simultaneously and independently. The main goals of this research project are to develop an animal mouse model injected with an associated adenovirus (AAV) and an imaging protocol to study neurovascular coupling in vivo using 2-photon microscopy. This imaging modality makes it possible to excite and image fluorescent structures at high spatial resolution. This method of microscopy has the advantage of producing images containing information coming only from the focal plane, and of allowing a greater depth of penetration compared to other standard microscopy techniques. In this project, an animal model was developed and optimized to express the fluorescent protein GCaMP6s in the cell body of excitatory and inhibitory neurons in adult mice. This animal model also expresses the Texas Red fluorophore which is a blood plasma marker. The parameters of the 2-photon microscope were determined to image and measure neuronal activity as well as to image the cerebral vasculature simultaneously and independently in the somatosensory cortex which is connected to the movements of the whiskers. The measurements acquired demonstrate that this imaging technique and this animal model make it possible to obtain information on neuronal activity with and without stimulation in anesthetized or awake mice. The external stimuli applied to the imaged mouse are puffs of air delivered to the whiskers on one side of the mouse's muzzle. Images of the vascular structure were obtained with the Gaussian beam of the 2-photon microscope, but also with the Bessel beam which makes it possible to acquire volumetric images. The study of the neurovascular coupling of this animal model was made under a 2-photon microscope by correlating the intensity of the signals emitted by GCaMP6s and by Texas Red. In addition, wide-field microscopy has been used to quantify hemodynamics throughout the cortex, and thus verify the correlation between blood oxygenation and neuronal activity. Finally, the possibility of measuring blood flow under a 2-photon microscope and detecting neuronal activity under a wide-field microscope was evaluated.

Un des défis majeurs en neurosciences est d’acquérir des images de neurones profondément dans le cerveau tout en gardant un champ de vue raisonnable et en causant le moins de dommage possible au tissu. Le premier projet décrit dans ce mémoire consiste en un système endoscopique à balayage laser. En utilisant des composantes micro-optique au bout d’une fibre monomode de 125 µm de diamètre, un laser vient être focalisé sur le côté de cette fibre à environ 60 µm de celle-ci. Un micro capillaire de verre de 250 µm de diamètre externe et 150 µm de diamètre interne sert de guide pour cette fibre dans l’échantillon. Le point focal possède un diamètre entre 2 et 3 µm et peut être balayé sur une même ligne horizontale à une vitesse de 30 Hz et sur un angle de 90o par un système construit spécialement pour suivre la géométrie cylindrique de l’endoscope. Un actuateur piezoélectrique déplace la fibre verticalement avec une résolution microscopique sur un intervalle de 400 µm pour compléter une image cylindrique. Le fait de collecter le signal de fluorescence sur le côté de la fibre facilite son utilisation lors de l’acquisition et permet d’acquérir des images sur des zones non affectées par la chirurgie. De plus, le champ de vue du système est contrôlé par l’angle de balayage et la translation verticale de la fibre, donc complètement indépendant du diamètre de celle-ci. En utilisant des longueurs de fibres à gradient d’indice différentes, il est également possible de modifier le champ de vue du système, sans modifier son diamètre. Il a été possible avec ce système d’acquérir des images de microglies dans le mésencéphale d’une souris CX3CR1-GFP. Le système est prêt à être utilisé pour de l’imagerie calcique sur une ligne de pixel. L’imagerie de cerveaux entiers peut révéler une panoplie d’informations permettant de mieux comprendre le développement neuronal à l’échelle microscopique, mais également macroscopique. De plus, visualiser le cerveau comme un tout permet de mieux conceptualiser comment différentes maladies l’affectent dans son ensemble plutôt que de s’intéresser qu’à certaines structures spécifiques. En ce moment, il existe deux défis quant à l’imagerie de cerveau de souris complet : 1) le temps d’acquisition souvent très long (plusieurs heures) et 2) la création d’une grande quantité de données qui requiert une gestion ordonnée et spécifique pour ce genre d’application. Pour pallier à ces défis, on présente dans ce mémoire un système d’imagerie volumétrique à excitation 1-photon ayant une résolution raisonnable, capable d’acquérir un cerveau de souris entier avec sectionnement optique en quelques minutes. Il s’agit d’une combinaison entre un système à grand champ et l’algorithme HiLo. Le champ de vue est ... / Imaging cells and axons in deep brain with minimal damage while keeping a sizable field of view remains a challenge, because it is difficult to optimize one without sacrificing the other. We propose a scanning method reminiscent of laser scanning microscopy to get a reasonable field of view with minimal damage deep in the brain. By using micro-optics at the tip of our 125 µm-diameter singlemode fiber inside a 250 µm capillary, we can create a focal spot on the side of the fiber at a distance of approximately 60 µm. The focal spot has a 2 µm diameter and can be scanned at up to 30 hertz by a custom scanning device over a 90 degree angular sweep on a single line. A piezoelectric actuator moves up and down the fiber to achieve a cylindrical scanning pattern. By having this side illumination, there is no need for surgical exposure of the tissue, making our method simple and easy to achieve. The field of view is controlled by the angular and vertical sweeps, unrelated to the fiber diameter. Furthermore, by modifying the length of the grin lens, we could directly increase or decrease the field of view of our optical system, without any change on the probe diameter. We have succeeded in imaging microglia in the midbrain of a CX3CR1-GFP mouse. The system is also ready for calcium imaging on single pixel lines. Imaging whole mouse brains can provide a wealth of information for understanding neuronal development at both the microscopic and macroscopic scale. Furthermore, visualizing entire brain samples allow us to better conceptualize how different diseases affect the brain as a whole, rather than only investigating a certain structure. Currently, two main challenges exist in achieving whole mouse brain imaging: 1) Long image acquisition sessions (on the order of several hours) and 2) Big data creation and management due to the large, high-resolution image volumes created. To overcome these challenges, we present a fast 1-photon system with a slightly decreased resolution allowing whole brain, optically sectioned imaging on the order of minutes by using a mathematical algorithm termed “HiLo”. Our large field of view (25 mm2 ) allows us to see an entire newborn mouse brain in a single snapshot with a resolution of about 2 µm in lateral direction and 4 µm in axial direction. This resolution still allows visualization of cells and some large axonal projections. This technological advancement will first and foremost allow us to rapidly image large volume samples and store them in a smaller format without losing the integral information, which is mainly stained-cell quantity and location. Secondly, the design will allow for increased successful high-resolution imaging by screening ...

Ce présent projet de maîtrise porte sur le développement et l'optimisation d'une technique d'imagerie volumétrique rapide à grand champ, appelée la microscopie HiLo, pour imager l'activité calcique du cerveau de poisson-zèbres transgéniques GCaMP au stade juvénile. La microscopie HiLo peut effectivement amener divers avantages au domaine, tels que les faibles coûts et la facilité de conception et d'alignement, tout en procurant des performances d'imagerie similaires aux techniques déjà utilisées dans le domaine. Elle produit des images sectionnées optiquement en combinant deux images à grand champ pour extraire les informations provenant uniquement du plan focal : une à illumination uniforme et l'autre à illumination à tavelures laser. Le contraste des tavelures laser est un paramètre intéressant pour moduler l'épaisseur du sectionnement optique selon les besoins. Dans ce projet, un module Python est développé pour aider à la conception optique, ce qui est employé pour concevoir et construire le microscope HiLo avec les composantes optiques optimales. Le microscope est testé de multiple façon expérimentalement, définissant ses paramètres d'imagerie et démontrant ses performances. Un des aspects les plus intéressants du système est l'incorporation d'une lentille à focale variable pour produire des images volumétriques ainsi qu'un réducteur de tavelures laser pour alterner entre les deux types d'illumination. Beaucoup de travail est fait en ce qui concerne leur optimisation et synchronisation dans le système HiLo. L'algorithme permettant de produire des images sectionnées optiquement avec les deux images brutes à grand champ est développé en langage de programmation Python pour faciliter son utilisation future. Finalement, l'utilisation du microscope HiLo pour acquérir des images d'activité calcique du cerveau de poisson-zèbres permet de conclure que cette technique est prometteuse pour obtenir de l'information sur les connectivités du cerveau selon différents stimuli et stades de développement compte tenu de sa rapidité d'acquisition, son sectionnement optique et son faible coût. / The goal of this master's project is to optimize and develop a widefield imaging technique called HiLo microscopy for fast volumetric calcium imaging in a juvenile transgenic zebrafish brain expressing GCaMP. HiLo microscopy brings multiple advantages to the field, such as the low cost and the ease to design and align it and its performance is comparable to techniques already used in the field. The HiLo technique produces optically sectioned images by combining two raw widefield images to extract the information coming exclusively from the focal plane only. The first of the two images is acquired with a uniform illumination and the second is acquired with a speckle illumination. The speckle contrast is an interesting parameter to tune the optical sectioning thickness because they are indicators of objects' depth position. In this project, a Python module is developed to simulate optical design and calculations, which is then used to design the HiLo microscope with the most optimal optical components. The microscope's function is also tested with many different experiments that define its imaging parameters and demonstrates its performances. Some of the most interesting aspects of this system are the use of an electrically tunable lens to scan the sample in depth and a laser speckle reducer that is used to switch between the uniform and speckle illumination patterns. A significant amount of work is done to optimize and synchronize the components in the system. Next, the algorithm used to produce the optically sectioned images is also developed in this project with the Python programming language to facilitate its future usage. Finally, the HiLo microscope is used to produce calcium imaging acquisitions of zebrafish brains, which show that HiLo microscopy is promising to obtain connectivity information of the brain with different stimuli and at different developmental stages due to its fast acquisition speed, optical sectioning and low cost.