679 research outputs found

    Rehabilitative devices for a top-down approach

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    In recent years, neurorehabilitation has moved from a "bottom-up" to a "top down" approach. This change has also involved the technological devices developed for motor and cognitive rehabilitation. It implies that during a task or during therapeutic exercises, new "top-down" approaches are being used to stimulate the brain in a more direct way to elicit plasticity-mediated motor re-learning. This is opposed to "Bottom up" approaches, which act at the physical level and attempt to bring about changes at the level of the central neural system. Areas covered: In the present unsystematic review, we present the most promising innovative technological devices that can effectively support rehabilitation based on a top-down approach, according to the most recent neuroscientific and neurocognitive findings. In particular, we explore if and how the use of new technological devices comprising serious exergames, virtual reality, robots, brain computer interfaces, rhythmic music and biofeedback devices might provide a top-down based approach. Expert commentary: Motor and cognitive systems are strongly harnessed in humans and thus cannot be separated in neurorehabilitation. Recently developed technologies in motor-cognitive rehabilitation might have a greater positive effect than conventional therapies

    Integrating EEG and MEG signals to improve motor imagery classification in brain-computer interfaces

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    We propose a fusion approach that combines features from simultaneously recorded electroencephalographic (EEG) and magnetoencephalographic (MEG) signals to improve classification performances in motor imagery-based brain-computer interfaces (BCIs). We applied our approach to a group of 15 healthy subjects and found a significant classification performance enhancement as compared to standard single-modality approaches in the alpha and beta bands. Taken together, our findings demonstrate the advantage of considering multimodal approaches as complementary tools for improving the impact of non-invasive BCIs

    Hybridizing 3-dimensional multiple object tracking with neurofeedback to enhance preparation, performance, and learning

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    Le vaste domaine de l’amĂ©lioration cognitive traverse les applications comportementales, biochimiques et physiques. Aussi nombreuses sont les techniques que les limites de ces premiĂšres : des Ă©tudes de pauvre mĂ©thodologie, des pratiques Ă©thiquement ambiguĂ«s, de faibles effets positifs, des effets secondaires significatifs, des couts financiers importants, un investissement de temps significatif, une accessibilitĂ© inĂ©gale, et encore un manque de transfert. L’objectif de cette thĂšse est de proposer une mĂ©thode novatrice d’intĂ©gration de l’une de ces techniques, le neurofeedback, directement dans un paradigme d’apprentissage afin d’amĂ©liorer la performance cognitive et l’apprentissage. Cette thĂšse propose les modalitĂ©s, les fondements empiriques et des donnĂ©es Ă  l’appui de ce paradigme efficace d’apprentissage ‘bouclé’. En manipulant la difficultĂ© dans une tĂąche en fonction de l’activitĂ© cĂ©rĂ©brale en temps rĂ©el, il est dĂ©montrĂ© que dans un paradigme d’apprentissage traditionnel (3-dimentional multiple object tracking), la vitesse et le degrĂ© d’apprentissage peuvent ĂȘtre amĂ©liorĂ©s de maniĂšre significative lorsque comparĂ©s au paradigme traditionnel ou encore Ă  un groupe de contrĂŽle actif. La performance amĂ©liorĂ©e demeure observĂ©e mĂȘme avec un retrait du signal de rĂ©troaction, ce qui suggĂšre que les effets de l’entrainement amĂ©liorĂ© sont consolidĂ©s et ne dĂ©pendent pas d’une rĂ©troaction continue. Ensuite, cette thĂšse rĂ©vĂšle comment de tels effets se produisent, en examinant les corrĂ©lĂ©s neuronaux des Ă©tats de prĂ©paration et de performance Ă  travers les conditions d’état de base et pendant la tĂąche, de plus qu’en fonction du rĂ©sultat (rĂ©ussite/Ă©chec) et de la difficultĂ© (basse/moyenne/haute vitesse). La prĂ©paration, la performance et la charge cognitive sont mesurĂ©es via des liens robustement Ă©tablis dans un contexte d’activitĂ© cĂ©rĂ©brale fonctionnelle mesurĂ©e par l’électroencĂ©phalographie quantitative. Il est dĂ©montrĂ© que l’ajout d’une assistance- Ă -la-tĂąche apportĂ©e par la frĂ©quence alpha dominante est non seulement appropriĂ©e aux conditions de ce paradigme, mais influence la charge cognitive afin de favoriser un maintien du sujet dans sa zone de dĂ©veloppement proximale, ce qui facilite l’apprentissage et amĂ©liore la performance. Ce type de paradigme d’apprentissage peut contribuer Ă  surmonter, au minimum, un des limites fondamentales du neurofeedback et des autres techniques d’amĂ©lioration cognitive : le manque de transfert, en utilisant une mĂ©thode pouvant ĂȘtre intĂ©grĂ©e directement dans le contexte dans lequel l’amĂ©lioration de la performance est souhaitĂ©e.The domain of cognitive enhancement is vast, spanning behavioral, biochemical and physical applications. The techniques are as numerous as are the limitations: poorly conducted studies, ethically ambiguous practices, limited positive effects, significant side-effects, high financial costs, significant time investment, unequal accessibility, and lack of transfer. The purpose of this thesis is to propose a novel way of integrating one of these techniques, neurofeedback, directly into a learning context in order to enhance cognitive performance and learning. This thesis provides the framework, empirical foundations, and supporting evidence for a highly efficient ‘closed-loop’ learning paradigm. By manipulating task difficulty based on a measure of cognitive load within a classic learning scenario (3-dimentional multiple object tracking) using real-time brain activity, results demonstrate that over 10 sessions, speed and degree of learning can be substantially improved compared with a classic learning system or an active sham-control group. Superior performance persists even once the feedback signal is removed, which suggests that the effects of enhanced training are consolidated and do not rely on continued feedback. Next, this thesis examines how these effects occur, exploring the neural correlates of the states of preparedness and performance across baseline and task conditions, further examining correlates related to trial results (correct/incorrect) and task difficulty (slow/medium/fast speeds). Cognitive preparedness, performance and load are measured using well-established relationships between real-time quantified brain activity as measured by quantitative electroencephalography. It is shown that the addition of neurofeedback-based task assistance based on peak alpha frequency is appropriate to task conditions and manages to influence cognitive load, keeping the subject in the zone of proximal development more often, facilitating learning and improving performance. This type of learning paradigm could contribute to overcoming at least one of the fundamental limitations of neurofeedback and other cognitive enhancement techniques : a lack of observable transfer effects, by utilizing a method that can be directly integrated into the context in which improved performance is sought

    Towards Improving Learning with Consumer-Grade, Closed-Loop, Electroencephalographic Neurofeedback

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    Learning is an enigmatic process composed of a multitude of cognitive systems that are functionally and neuroanatomically distinct. Nevertheless, two undeniable pillars which underpin learning are attention and memory; to learn, one must attend, and maintain a representation of, an event. Psychological and neuroscientific technologies that permit researchers to “mind-read” have revealed much about the dynamics of these distinct processes that contribute to learning. This investigation first outlines the cognitive pillars which support learning and the technologies that permit such an understanding. It then employs a novel task—the amSMART paradigm—with the goal of building a real-time, closed-loop, electroencephalographic (EEG) neurofeedback paradigm using consumergrade brain-computer interface (BCI) hardware. Data are presented which indicate the current status of consumer-grade BCI for EEG cognition classification and enhancement, and directions are suggested for the developing world of consumer neurofeedback

    An integrative framework for tailoring virtual reality based motor rehabilitation after stroke

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    Stroke is a leading cause of life-lasting motor impairments, undermining the quality of life of stroke survivors and their families, and representing a major chal lenge for a world population that is ageing at a dramatic rate. Important technologi cal developments and neuroscientific discoveries have contributed to a better under standing of stroke recovery. Virtual Reality (VR) arises as a powerful tool because it allows merging contributions from engineering, human computer interaction, reha bilitation medicine and neuroscience to propose novel and more effective paradigms for motor rehabilitation. However, despite evidence of the benefits of these novel training paradigms, most of them still rely on the choice of particular technologi cal solutions tailored to specific subsets of patients. Here we present an integrative framework that utilizes concepts of human computer confluence to 1) enable VR neu rorehabilitation through interface technologies, making VR rehabilitation paradigms accessible to wide populations of patients, and 2) create VR training environments that allow the personalization of training to address the individual needs of stroke patients. The use of these features is demonstrated in pilot studies using VR training environments in different configurations: as an online low-cost version, with a myo electric robotic orthosis, and in a neurofeedback paradigm. Finally, we argue about the need of coupling VR approaches and neurocomputational modelling to further study stroke and its recovery process, aiding on the design of optimal rehabilitation programs tailored to the requirements of each user.info:eu-repo/semantics/publishedVersio

    Brain-Computer Interface and Motor Imagery Training: The Role of Visual Feedback and Embodiment

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    Controlling a brain-computer interface (BCI) is a difficult task that requires extensive training. Particularly in the case of motor imagery BCIs, users may need several training sessions before they learn how to generate desired brain activity and reach an acceptable performance. A typical training protocol for such BCIs includes execution of a motor imagery task by the user, followed by presentation of an extending bar or a moving object on a computer screen. In this chapter, we discuss the importance of a visual feedback that resembles human actions, the effect of human factors such as confidence and motivation, and the role of embodiment in the learning process of a motor imagery task. Our results from a series of experiments in which users BCI-operated a humanlike android robot confirm that realistic visual feedback can induce a sense of embodiment, which promotes a significant learning of the motor imagery task in a short amount of time. We review the impact of humanlike visual feedback in optimized modulation of brain activity by the BCI users

    Brain enhancement through cognitive training: A new insight from brain connectome

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    Owing to the recent advances in neurotechnology and the progress in understanding of brain cognitive functions, improvements of cognitive performance or acceleration of learning process with brain enhancement systems is not out of our reach anymore, on the contrary, it is a tangible target of contemporary research. Although a variety of approaches have been proposed, we will mainly focus on cognitive training interventions, in which learners repeatedly perform cognitive tasks to improve their cognitive abilities. In this review article, we propose that the learning process during the cognitive training can be facilitated by an assistive system monitoring cognitive workloads using electroencephalography (EEG) biomarkers, and the brain connectome approach can provide additional valuable biomarkers for facilitating leaners' learning processes. For the purpose, we will introduce studies on the cognitive training interventions, EEG biomarkers for cognitive workload, and human brain connectome. As cognitive overload and mental fatigue would reduce or even eliminate gains of cognitive training interventions, a real-time monitoring of cognitive workload can facilitate the learning process by flexibly adjusting difficulty levels of the training task. Moreover, cognitive training interventions should have effects on brain sub-networks, not on a single brain region, and graph theoretical network metrics quantifying topological architecture of the brain network can differentiate with respect to individual cognitive states as well as to different individuals' cognitive abilities, suggesting that the connectome is a valuable approach for tracking the learning progress. Although only a few studies have exploited the connectome approach for studying alterations of the brain network induced by cognitive training interventions so far, we believe that it would be a useful technique for capturing improvements of cognitive function

    Post-stroke Rehabilitation of Severe Upper Limb Paresis in Germany – Toward Long-Term Treatment With Brain-Computer Interfaces

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    Severe upper limb paresis can represent an immense burden for stroke survivors. Given the rising prevalence of stroke, restoration of severe upper limb motor impairment remains a major challenge for rehabilitation medicine because effective treatment strategies are lacking. Commonly applied interventions in Germany, such as mirror therapy and impairment-oriented training, are limited in efficacy, demanding for new strategies to be found. By translating brain signals into control commands of external devices, brain-computer interfaces (BCIs) and brain-machine interfaces (BMIs) represent promising, neurotechnology-based alternatives for stroke patients with highly restricted arm and hand function. In this mini-review, we outline perspectives on how BCI-based therapy can be integrated into the different stages of neurorehabilitation in Germany to meet a long-term treatment approach: We found that it is most appropriate to start therapy with BCI-based neurofeedback immediately after early rehabilitation. BCI-driven functional electrical stimulation (FES) and BMI robotic therapy are well suited for subsequent post hospital curative treatment in the subacute stage. BCI-based hand exoskeleton training can be continued within outpatient occupational therapy to further improve hand function and address motivational issues in chronic stroke patients. Once the rehabilitation potential is exhausted, BCI technology can be used to drive assistive devices to compensate for impaired function. However, there are several challenges yet to overcome before such long-term treatment strategies can be implemented within broad clinical application: 1. developing reliable BCI systems with better usability; 2. conducting more research to improve BCI training paradigms and 3. establishing reliable methods to identify suitable patients

    Design of Cognitive Interfaces for Personal Informatics Feedback

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