A brain-machine interface (BMI) uses signals from the brain to control electronic devices. One application of this technology is the control of assistive devices to facilitate movement after paralysis. Ideally, the BMI would identify an intended movement and control an assistive device to produce the desired movement. To implement such a system, it is necessary to identify different movements involving a single limb and users must be able to issue commands at any instant instead of only during specific time windows determined by the BMI itself. A novel processing technique to identify voluntary movements using only four electrodes is presented. Histograms containing the spectral components of intracranial neural signals displaying power changes correlated with movement were unique for each of three movements performed with one limb. Off-line classification of the histograms allowed the identification of the performed movement with an accuracy of 89%. This movement identification system was interfaced with a neuroprosthesis for grasping, fitted to a tetraplegic individual. The user pressed a button triggering the random selection and classification of a brain signal previously recorded intracranially from a different person while performing specific arm movements. Correct identification of the movement triggered grasping functions. Movement identification accuracy was 94% allowing successful operation of the neuroprosthesis. Finally, two BMIs for the real-time asynchronous control of two-dimensional movements were created using a single electrode. One EEG-based system was tested by a healthy participant. A second system was implemented and tested using recordings from an individual undergoing clinical intracranial electrode implantation. The users modulated their 7 Hz-13 Hz oscillatory rhythm through motor imagery. A power decrease below a threshold activated a ``brain-switch''. This switch was coupled with a novel asynchronous control strategy to control a miniature remotely-controlled vehicle as well as a computer cursor. Successful operation of the EEG system required 6 hrs of training. ECoG control was achieved after only 15 minutes. The operation of the BMI was simple enough to allow users to focus on the task at hand rather than on the actual operation of the BMI.

A brain-machine interface (BMI) uses signals from the brain to control electronic devices. One application of this technology is the control of assistive devices to facilitate movement after paralysis. Ideally, the BMI would identify an intended movement and control an assistive device to produce the desired movement. To implement such a system, it is necessary to identify different movements involving a single limb and users must be able to issue commands at any instant instead of only during specific time windows determined by the BMI itself. A novel processing technique to identify voluntary movements using only four electrodes is presented. Histograms containing the spectral components of intracranial neural signals displaying power changes correlated with movement were unique for each of three movements performed with one limb. Off-line classification of the histograms allowed the identification of the performed movement with an accuracy of 89%. This movement identification system was interfaced with a neuroprosthesis for grasping, fitted to a tetraplegic individual. The user pressed a button triggering the random selection and classification of a brain signal previously recorded intracranially from a different person while performing specific arm movements. Correct identification of the movement triggered grasping functions. Movement identification accuracy was 94% allowing successful operation of the neuroprosthesis. Finally, two BMIs for the real-time asynchronous control of two-dimensional movements were created using a single electrode. One EEG-based system was tested by a healthy participant. A second system was implemented and tested using recordings from an individual undergoing clinical intracranial electrode implantation. The users modulated their 7 Hz-13 Hz oscillatory rhythm through motor imagery. A power decrease below a threshold activated a ``brain-switch''. This switch was coupled with a novel asynchronous control strategy to control a miniature remotely-controlled vehicle as well as a computer cursor. Successful operation of the EEG system required 6 hrs of training. ECoG control was achieved after only 15 minutes. The operation of the BMI was simple enough to allow users to focus on the task at hand rather than on the actual operation of the BMI.

No description available.

Les Interfaces Cerveau Ordinateur Actives (ICOs) permettent à une personne d'exercer un contrôle direct et volontaire sur un système informatique par interprétation de son activité cérébrale : certains signaux du cerveau sont capturés afin que le système reconnaisse des actions imaginées spécifiques (mouvements, images, concepts). Les ICOs actives et leurs utilisateurs doivent être entrainés. Cet entraînement rend les signaux plus aisés à reconnaître par le système.Cependant, à l'heure actuelle les ICO servent principalement dans un contexte médical pour aider les personnes en situation de handicap (moteur, ou empêchant complètement la communication avec le monde extérieur) et se trouvent rarement en dehors de laboratoires spécialisés.Les ICO ont de nombreuses limitations :• La variabilité dans les signaux: les signaux sont différents d'une personne à l'autre voire même chez un même individu à des moments différents.• Des sessions d'entraînement longues et répétitives: entre dix minutes et deux mois, sont ennuyantes et désengagent les utilisateurs du processus d'apprentissage.• Un feedback limité: les systèmes actuels proposent un feedback unimodal élémentaire qui est inadapté pour les nombreux utilisateurs. la communication est unidirectionnelle dans le sens où le système donne des instructions que l'utilisateur doit exécuter.L'objectif de cette thèse est de proposer des solutions aux problèmes sus décrits afin d'obtenir une architecture consistante qui rendra les ICO plus compatibles avec les applications d'IHM. L'idée principale est l'implantation du co-apprentissage dans la boucle ICO et l'exploration de la manière dont les utilisateurs et le système peuvent mutuellement se donner du feedback dans le but de l'amélioration de l'utilisabilité des ICO.Cette thèse se structure autour de trois innovations portant sur la boucle ICO :• Une architecture générale basée sur les principes des ICO asynchrones et sur l'entraînement incrémental combinés avec une séparation aveugle des sources et un classifieur à distance minimum. Nous évaluerons l'architecture sur une tache de pilotage de drone au long d'un mois et concluons qu'elle est en adéquation avec les besoins d'une utilisation quotidienne ludique.• Une modalité de visualisation plus intuitive pour les résultats de classification ainsi que pour les caractéristiques de distance sur la base d'une projection en coordonnées de Wachspress pour un nombre arbitraire de classes. Nous combinons la visualisation avec un feedback direct des utilisateurs leur permettant d'interactivement changer la marge de classification, le type de distance où encore de trier et de gérer les signaux d'entraînement en temps réel. Nous évaluons cette contribution sur un jeu de tir simple et découvrons qu'il y a une bonne synergie entre la modalité de visualisation et le feedback direct des utilisateurs et qu'une telle combinaison est bien plus agréable à utiliser qu'un entraînement d'ICO standard.• Enfin, nous développons une ICO fonctionnelle à base d'imagerie conceptuelle à l'aide de notre architecture ainsi que de nos systèmes de visualisation et de feedback, ce qui permet une interaction plus agréable au travers de l'imagination de catégories sémantiques et de concepts. Nous démontrons que ce type d'ICO détecte plus aisément les catégories sémantiques éloignées plutôt que les catégories sémantiques proches. Pour terminer, nous créons un nouveau protocole d'entraînement implicite pour les ICO à base d'Imagerie Conceptuelle basé sur l'amorçage sémantique et conceptuel, ce qui permet d'intégrer l'entraînement dans le scénario et l'environnement d'une jeu vidéo sans que l'utilisateur n'en soit conscient. Notre protocole mène à une meilleure immersion et à meilleur sentiment de flot vis à vis du jeu. / Active Brain Computer Interfaces (BCIs) allow people to exert direct voluntary control over a computer system: their brain signals are captured and the system recognizes specific imagined actions (movements, images, concepts). Active BCIs and their users must undergo training. This makes the signals easier to recognize by the system. This acquisition can take from 10 minutes up to 2 months. BCIs can thus be applied to many control and interaction scenarios of our everyday lives, especially in relation to entertainment (Wolpaw et al., 2002).BCIs are mostly used by disabled people in a medical setting and seldom leave the lab. First of all, high-grade equipment is expensive and non-portable. Although there are commercial ventures proposing BCI acquisition equipment to the general public, the quality is still insufficient to build accurate and robust BCIs.BCIs also suffer from numerous limitations:• Variability of the signals: signals different across people or within the same individual at different times.• Long and repetitive training sessions: between 10 minutes up to several months, disengage and bore users.• Limited feedback: simple unimodal feedback ill adapted for many users. Feedback is unidirectional and the user just has to follow instructions.All these issues limit the adoption of BCI, the lack of widespread commercial success and the use of BCI from human computer interaction applications.The objective of the thesis is to propose solutions to the above problems so as to obtain a consistent architecture that will allow BCIs to be better suitable to Human-Computer Interaction (HCI) applications. The idea is to implement co-learning in the BCI loop and to explore how users and system can give feedback to each other in order to improve BCI usability.This thesis is structured around three innovations surrounding the BCI loop:• A general architecture based on asynchronous BCI principles and on incremental training combined with an unsupervised blind-source separation filter and a minimum distance classifier. This architecture allows producing BCIs with minimal training session. We evaluate the architecture on a drone piloting task over a month and find that it is suitable for use in daily recreational applications.• A more intuitive visualization modality for classification outcomes and distance features using Wachspress coordinate projection for an arbitrary number of classes. We combine the visualization with direct feedback mechanism where users can interactively change the classification margin, change the types of features as well as edit the training trials in real-time. We evaluate our contribution on a simple shooter game and find there is a good synergy between our visualization modality and direct user feedback and that the combination is much more enjoyable to users than a standard BCI training.• Finally we develop an operational Conceptual Imagery BCI based on our architecture, visualization and feedback system that allow for more natural interactions through the imagination of sematic categories and concepts. We show that this type of BCI is more effective at detecting distinct semantic categories rather than close ones. Then, we build on this conceptual BCI to propose a smart home control system for healthy and disabled users. Finally we invent a new seamless training protocol for Conceptual Imagery that uses conceptual and semantic priming in order to integrate the training in the narrative and environment of the game without the realization of the user. Our technique leads to better flow and immersion of users in the game. We believe this training protocol can be extended to many tasks outside of games or even of Conceptual Imagery.

Cette thèse a pour but le développement d’une Interface cerveau-machine (ICM) à partir de la mesure EEG,permettant à l’utilisateur de communiquer avec un dispositif externe directement par l’intermédiaire de son activité cérébrale. Ces travaux ont été menés avec comme ligne directrice le développement d'un système d'ICM utilisable dans un contexte de vie courante, le but étant de réaliser une ICM simple d'utilisation, robuste et ergonomique, permettant le contrôle d'un effecteur avec un temps de calibration minimal.Un brain-switch ou interrupteur cérébral a été réalisé et permet à l'utilisateur d'envoyer une commande binaire. La réalisation d'une telle ICM implique le développement d'algorithmes robustes et leurs mises en œuvre expérimentales. Les travaux réalisés comportent deux volets, l'un concerne le développement de nouveaux algorithmes, l'autre concerne la réalisation de campagne de tests. / This thesis presents the development of a Brain computer Interface (BCI) based on EEG signal, allowing its user to communicates with an external device solely by the mean of brain activity. This work as been conduct with the goal of designing a robust, ergonomic and easy to use BCI system for real life applications.In this context, a brain-switch has been developed, allowing it's user to send a binary command to a homeautomation system. This goal can only be achieved by developing new methodologies and algorithms, while testing them on real life experiments. Therefore, this works is two part, the first one is focus on the design of new algorithms, the secondon the design of experimental paradigm.

A presente pesquisa é uma etnografia da recepção da publicidade do Banco Comercial e de Investimentos (BCI) exibida em espaços comerciais de televisão, rádio e outdoors em Moçambique a partir do ponto de vista dos clientes do banco. O estudo foi realizado na Cidade de Maputo, capital de Moçambique. Os seus resultados sugerem que a nova estratégia comunicacional do BCI apropria-se de “cultura local” (signos e elementos simbólicos tidos como moçambicanos) para se reposicionar no mercado bancário local. Como corolário de “apropriação” de elementos identitarios “locais”, na imaginação e nos discursos dos interlocutores da pesquisa, o BCI é entendido como um banco privado moçambicano, um banco “daqui”, um banco que respeita a “cultura moçambicana”. Os resultados da pesquisa revelam, também, que a localidade presente nos anúncios do BCI, para os clientes do banco, figura como um pretexto para a reinvenção da nação moçambicana numa época em que o país é desafiado pelo capitalismo neoliberal cada vez mais mundializado. / This research is ethnography of bank customers’ perception of advertisement of the Commercial and Investment Bank (BCI) displayed in commercial spaces of television, radio and billboards in Mozambique. The study was conducted in Maputo, capital of Mozambique. Their results suggest that the new communication strategy of the BCI appropriates “local culture” (signs and symbolic elements taken as typically Mozambican) to reposition itself in the local banking market. As a corollary of this assimilation of elements of “local” identity in the imagination and in the discourses of the bank customers, BCI is understood by them as a Mozambican private bank, a bank “from here” (“um banco daqui”), and a bank with respects towards “Mozambican culture”. The survey concludes that for the bank customers the locality present in BCI advertisements figures as an argument for the reinvention of the Mozambican nation at a time when the increasingly globalizing country is challenged by neoliberal capitalism.

Avec les progrès technologiques réalisés au cours de ces dernières décennies, la complexité et les vitesses de fonctionnement des circuits intégrés ont beaucoup été augmentées. Bien que ces évolutions aient permis de diminuer les dimensions et les tensions d’alimentations des circuits, la compatibilité électromagnétique (CEM) des composants a fortement été dégradée. Identifiée comme étant un verrou technologique, la CEM est aujourd’hui l’une des principales causes de « re-design » des circuits car les problématiques liées aux mécanismes de génération et de couplage du bruit ne sont pas suffisamment étudiées lors de leur conception.Ce manuscrit présente donc une méthodologie visant à étudier la propagation du bruit à travers les circuits intégrés par mesures et par simulations. Afin d’améliorer nos connaissances sur la propagation d’interférences électromagnétiques (IEM) et les mécanismes de couplage à travers les circuits, nous avons conçu un véhicule de test développé dans la technologie SMOS8MV® 0,25 µm de Freescale Semiconductor. Dans ce circuit, plusieurs fonctions élémentaires telles qu’un bus d’E/S et des blocs numériques ont été implémentées. Des capteurs de tensions asynchrones ont également été intégrés sur différentes alimentations de la puce pour analyser la propagation des perturbations injectées sur les broches du composant (injection DPI) et sur les conducteurs permettant d’alimenter ce dernier (injection BCI). En outre, nous proposons différents outils pour faciliter la modélisation et les simulations d’immunité des circuits intégrés (extraction des modèles de PCB, approches de modélisation des systèmes d’injection, méthode innovante permettant de prédire et de corréler les niveaux de tension/ de puissance injectés lors de mesures d’immunité conduite, flot de modélisation). Chaque outil et méthode de modélisation proposés sont évalués sur différents cas test. Enfin, pour évaluer notre démarche de modélisation, nous l’appliquons sur un bloc numérique de notre véhicule de test et comparons les résultats de simulations aux différentes mesures internes et externes réalisées sur le circuit / With technological advances in recent decades, the complexity and operating speeds of integrated circuits have greatly increased. While these developments have reduced dimensions and supply voltages of circuits, electromagnetic compatibility (EMC) of components has been highly degraded. Identified as a technological lock, EMC is now one of the main causes of circuits re-designs because issues related to generating and coupling noise mechanisms are not sufficiently studied during their design. This manuscript introduces a methodology to study propagation of electromagnetic disturbances through integrated circuits by measurements and simulations. To improve our knowledge about propagation of electromagnetic interferences (EMI) and coupling mechanisms through integrated circuits, we designed a test vehicle developed in the SMOS8MV® 0.25µm technology from Freescale Semiconductor. In this circuit, several basic functions such as I/O bus and digital blocks have been implemented. Asynchronous on-chip voltage sensors have also been integrated on different supplies of the chip to analyze propagation of disturbances injected on supply pins and wires of the component (DPI and BCI injection). In addition, we propose various tools to facilitate modeling and simulations of Integrated Circuit’s immunity (PCB model extraction, injection systems modeling approaches, innovative method to predict and correlate levels of voltage / power injected during conducted immunity measurements, modeling flow). Each tool and modeling method proposed is evaluated on different test cases. To assess our modeling approach, we finally apply it on a digital block of our test vehicle and compare simulation results to various internal and external measurements performed on the circuit

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-10-02T22:27:19Z No. of bitstreams: 1 GabrielAlvesVasiljevicMendes_DISSERT.pdf: 3791566 bytes, checksum: e847396390a6b6ca2128eefd4423f561 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-10-06T23:26:09Z (GMT) No. of bitstreams: 1 GabrielAlvesVasiljevicMendes_DISSERT.pdf: 3791566 bytes, checksum: e847396390a6b6ca2128eefd4423f561 (MD5) / Made available in DSpace on 2017-10-06T23:26:09Z (GMT). No. of bitstreams: 1 GabrielAlvesVasiljevicMendes_DISSERT.pdf: 3791566 bytes, checksum: e847396390a6b6ca2128eefd4423f561 (MD5) Previous issue date: 2017-07-31 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Brain-computer interfaces (BCIs) are specialized systems that allow users to control a computer or a machine using their brain waves. BCI systems allow patients with severe physical impairments, such as those suffering from amyotrophic lateral sclerosis, cerebral palsy and locked-in syndrome, to communicate and regain physical movements with the help of specialized equipment. With the development of BCI technology in the second half of the 20th century and the advent of consumer-grade BCI devices in the late 2000s, brain-controlled systems started to find applications not only in the medical field, but in areas such as entertainment. One particular area that is gaining more evidence due to the arrival of consumer-grade devices is the field of computer games, which has become increasingly popular in BCI research as it allows for more user-friendly applications of BCI technology in both healthy and unhealthy users. However, numerous challenges are yet to be overcome in order to advance in this field, as the origins and mechanics of the brain waves and how they are affected by external stimuli are not yet fully understood. In this sense, a systematic literature review of BCI games based on consumer-grade technology was performed. Based on its results, two BCI games, one using attention and the other using meditation as control signals, were developed in order to investigate key aspects of player interaction: the influence of graphical elements on attention and control; the influence of auditory stimuli on meditation and work load; and the differences both in performance and multiplayer game experience, all in the context of neurofeedback-based BCI games.

A presente pesquisa é uma etnografia da recepção da publicidade do Banco Comercial e de Investimentos (BCI) exibida em espaços comerciais de televisão, rádio e outdoors em Moçambique a partir do ponto de vista dos clientes do banco. O estudo foi realizado na Cidade de Maputo, capital de Moçambique. Os seus resultados sugerem que a nova estratégia comunicacional do BCI apropria-se de “cultura local” (signos e elementos simbólicos tidos como moçambicanos) para se reposicionar no mercado bancário local. Como corolário de “apropriação” de elementos identitarios “locais”, na imaginação e nos discursos dos interlocutores da pesquisa, o BCI é entendido como um banco privado moçambicano, um banco “daqui”, um banco que respeita a “cultura moçambicana”. Os resultados da pesquisa revelam, também, que a localidade presente nos anúncios do BCI, para os clientes do banco, figura como um pretexto para a reinvenção da nação moçambicana numa época em que o país é desafiado pelo capitalismo neoliberal cada vez mais mundializado. / This research is ethnography of bank customers’ perception of advertisement of the Commercial and Investment Bank (BCI) displayed in commercial spaces of television, radio and billboards in Mozambique. The study was conducted in Maputo, capital of Mozambique. Their results suggest that the new communication strategy of the BCI appropriates “local culture” (signs and symbolic elements taken as typically Mozambican) to reposition itself in the local banking market. As a corollary of this assimilation of elements of “local” identity in the imagination and in the discourses of the bank customers, BCI is understood by them as a Mozambican private bank, a bank “from here” (“um banco daqui”), and a bank with respects towards “Mozambican culture”. The survey concludes that for the bank customers the locality present in BCI advertisements figures as an argument for the reinvention of the Mozambican nation at a time when the increasingly globalizing country is challenged by neoliberal capitalism.

Denna rapport har som syfte att samla erfarenhet kring de möjligheter och den potential som finns i den EEG-teknik och de BCI-headset från NeuroSky som använts. Detta görs genom design och utveckling av ett spel som utnyttjar tekniken. Det finns redan idag ett mindre urval av sådana spel, men dessa har samtliga varit av mycket trivial karaktär och med en bristande förmåga att övertyga och engagera. Samtidigt som EEG-teknik når ut till konsumenter, ökar också allmänintresset för mental träning. Studier och rapporter visar indikationer på att sådan träning inte bara förbättrar hjärnans effektivitet, utan också kan förebygga vissa neurologiska sjukdomar som Alzheimers och demens. Forskningsrapporter pekar också på att spel med fördel kan användas för mental träning, vilket är en motivering till relevansen i att detta examensarbete representeras i form av ett spel. Hårdvaran som använts har färdiga algoritmer för avläsning av användarens koncentrations-, meditations- och blinkstyrkenivåer. Det bristande antalet olika former av input som enheterna kan leverera i sitt standardutförande, skapar begränsningar i komplexiteten på interaktionen. Trots detta har det kunnat konstateras som ett resultat av detta arbete att en betydligt rikare interaktionsmodell än den som idag ofta påträffas i tillgängliga spel, är fullt möjlig. Cortex Wars, som det utvecklade spelet heter, tänjer på gränserna genom att vara det första spelet för två samtidiga spelare; var och en med varsitt NeuroSky headset. Resultaten av arbetet visar också på att tekniken och den hårdvara som använts inte är utan problem och brister. Stabilitetsproblem finns med hårdvaran och tekniken som sådan är också väldigt känslig för yttre påverkan av exempelvis muskelaktivitet. EEG-teknik i den form som använts i arbetet har stor potential att förändra tillvaron och tillgängligheten för en stor grupp människor i flera avseenden. Här avhandlas främst spelområdet och hur detta kan tillgängliggöras på sådant vis att personer med vissa fysiska handikapp har möjlighet att spela på lika villkor som människor utan handikapp.