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- Is it necessary to show virtual limbs in action observation neurorehabilitation systems?Publication . Modroño, Cristián; Bermúdez, Sergi; Cameirão, Mónica; Pereira, Fábio; Paulino, Teresa; Marcano, Francisco; Hernández-Martín, Estefanía; Plata-Bello, Julio; Palenzuela, Nereida; Núñez-Pádron, Daniel; Pérez-González, José M; González-Mora, José LAction observation neurorehabilitation systems are usually based on the observation of a virtual limb performing different kinds of actions. In this way, the activity in the frontoparietal Mirror Neuron System is enhanced, which can be helpful to rehabilitate stroke patients. However, the presence of limbs in such systems might not be necessary to produce mirror activity, for example, frontoparietal mirror activity can be produced just by the observation of virtual tool movements. The objective of this work was to explore to what point the presence of a virtual limb impacts the Mirror Neuron System activity in neurorehabilitation systems.
- Augmented Human Assistance (AHA)Publication . Bermúdez i Badia, Sergi; Odekerken-Schröder, Gaby; Mahr, Dominik; Čaić, Martina; Lee, Min Hun; Siewiorek, Dan; Smailagic, Assim; Gamboa, Hugo; Belo, David; Carnide, Maria Filomena Araújo da Costa Cruz; Baptista, Maria de Fátima Marcelina; Simão, Hugo; Avelino, João; Sousa, Honorato; Paulino, Teresa; Gonçalves, Afonso; Cardona, John Muñoz; Cameirão, Mónica S.; Bernardino, Alexandre; Gouveia, Élvio RúbioAging and sedentarism are two main challenges for social and health systems in modern societies. To face these challenges a new generation of ICT based solutions is being developed to promote active aging, prevent sedentarism and find new tools to support the large populations of patients that suffer chronic conditions as result of aging. Such solutions have the potential to transform healthcare by optimizing resource allocation, reducing costs, improving diagno ses and enabling novel therapies, thus increasing quality of life. The primary goal of the “AHA: Augmented Human Assistance” project is to de velop novel assistive technologies to promote exercise among the elderly and patients of motor disabilities. For exercise programs to be effective, it is essential that users and patients comply with the prescribed schedule and perform the ex ercises following established protocols. Until now this has been achieved by hu man monitoring in rehabilitation and therapy session, where the clinicians or therapists permanently accompany users or patient. In many cases, exercises are prescribed for home performance, in which case it is not possible to validate their execution. In this context, the AHA project is an integrative and cross-discipli nary approach of 4 Portuguese universities, the CMU, and 2 Portuguese industry partners, that combines innovation and fundamental research in the areas of hu man-computer interaction, robotics, serious games and physiological computing (see partner list in Appendix A). In the project, we capitalize on recent innova tions and aim at enriching the capabilities and range of application of assistive devices via the combination of (1) assistive robotics; (2) technologies that use well-understood motivational techniques to induce people to do their exercises in the first place, and to do them correctly and completely; (3) tailored and relevant guidance in regard to health care and social support and activities; and (4) tech nologies to self-monitoring and sharing of progress with health-care provider enabling clinicians to fine-tune the exercise regimen to suit the participant’s ac tual progress. We highlight the development of a set of exergames (serious games controlled by the movement of the user’s body limbs) specifically designed for the needs of the target population according to best practices in sports and human kinetics sciences. The games can be adapted to the limitations of the users (e.g. to play in a sitting position) so a large fraction of the population can benefit from them. The games can be executed with biofeedback provided from wearable sensors, to pro duce more controlled exercise benefits. The games can be played in multi-user settings, either in cooperative or competitive mode, to promote the social rela tions among players. The games contain regional motives to trigger memories from the past and other gamification techniques that keep the users involved in the exercise program. The games are projected in the environment through aug mented reality techniques that create a more immersive and engaging experience than conventional displays. Virtual coach techniques are able to monitor the cor rectness of the exercise and provide immediate guidance to the user, as well as providing reports for therapists. A socially assistive robot can play the role of the coach and provide an additional socio-cognitive dimension to the experience to complement the role of the therapist. A web service that records the users’ per formances and allows the authorized therapists to access and configure the exer cise program provides a valuable management tool for caregivers and clinical staff. It can also provide a social network for players, increasing adherence to the therapies. We have performed several end-user studies that validate the proposed ap proaches. Together, or in isolation, these solutions provide users, caregivers, health professionals and institutions, valuable tools for health promotion, disease monitoring and prevention.
- PASAR: an integrated model of prediction, anticipation, sensation, attention and response for artificial sensorimotor systemsPublication . Mathews, Zenon; Bermúdez i Badia, Sergi; Verschureab, Paul F.M.JA wide range of neuroscientific studies suggest the existence of cognitive mechanisms like attention, prediction, anticipation and strong vertical interactions between different hierarchical layers of the brain while performing complex tasks. Despite advances in both cognitive brain research and in the development of brain-inspired artificial cognitive systems, the interplay of these key ingredients of cognition remain largely elusive and unquantified in complex real-world tasks. Furthermore, it has not yet been demonstrated how a self-contained hierarchical cognitive system acting under limited resource constraints can quantifiably benefit from the incorporation of top–down and bottom–up attentional mechanisms. In this context, an open fundamental question is how a data association mechanism can integrate bottom–up sensory information and top–down knowledge. Here, building on the Distributed Adaptive Control (DAC) architecture, we propose a single framework for integrating these different components of cognition and demonstrate the framework’s performance in solving real-world and simulated robot tasks. Using the model we quantify the interactions between prediction, anticipation, attention and memory. Our results support the strength of a complete system that incorporates attention, prediction and anticipation mechanisms compared to incomplete systems for real-world and complex tasks. We unveil the relevance of transient memory that underlines the utility of the above mechanisms for intelligent knowledge management in artificial sensorimotor systems. These findings provide concrete predictions for physiological and psychophysical experiments to validate our model in biological cognitive systems.
- Automating senior fitness testing through gesture detection with depth sensorsPublication . Gonçalves, A. R.; Cameirão, M. S.; Bermúdez i Badia, S.; Gouveia, E. R.Sedentarism has a negative impact on health, life expectancy and quality of life, especially in older adults. The assessment of functional fitness helps evaluating the effects of ageing and sedentarism, and this assessment is typically done through validated battery tests such as the Senior Fitness Test (SFT). In this paper we present a computer-based system for assisting and automating SFT administration and scoring in the elderly population. Our system assesses lower body strength, agility and dynamic balance, and aerobic endurance making use of a depth sensor for body tracking and multiple gesture detectors for the evaluation of movement execution. The system was developed and trained with optimal data collected in laboratory conditions and its performance was evaluated in a real environment with 22 elderly end-users, and compared to traditional SFT administered by an expert. Results show a high accuracy of our system in identifying movement patterns (>95%) and consistency with the traditional fitness assessment method. Our results suggest that this technology is a viable low cost option to assist in the fitness assessment of elderly that could be deployed for at home use in the context of fitness programs.
- Virtual reality based rehabilitation speeds up functional recovery of the upper extremities after stroke: a randomized controlled pilot study in the acute phase of stroke using the rehabilitation gaming systemPublication . Cameirão, Mónica da Silva; Bermúdez i Badia, Sergi; Duarte, Esther; Verschure, Paul F. M. J.Given the incidence of stroke, the need has arisen to consider more self-managed rehabilitation approaches. A promising technology is Virtual Reality (VR). Thus far, however, it is not clear what the benefits of VR systems are when compared to conventional methods. Here we investigated the clinical impact of one such system, the Rehabilitation Gaming System (RGS), on the recovery time course of acute stroke. RGS combines concepts of action execution and observation with an automatic individualization of training. METHODS. Acute stroke patients (n = 8) used the RGS during 12 weeks in addition to conventional therapy. A control group (n = 8) performed a time matched alternative treatment, which consisted of intense occupational therapy or non-specific interactive games. RESULTS. At the end of the treatment, between-group comparisons showed that the RGS group displayed significantly improved performance in paretic arm speed that was matched by better performance in the arm subpart of the Fugl-Meyer Assessment Test and the Chedoke Arm and Hand Activity Inventory. In addition, the RGS group presented a significantly faster improvement over time for all the clinical scales during the treatment period. CONCLUSIONS. Our results suggest that rehabilitation with the RGS facilitates the functional recovery of the upper extremities and that this system is therefore a promising tool for stroke neurorehabilitation.
- NeuRow: an immersive VR environment for motor-imagery training with the use of brain-computer interfaces and vibrotactile feedbackPublication . Bermúdez i Badia, Sergi; Ferreira, André; Vourvopoulos, AthanasiosMotor-Imagery offers a solid foundation for the development of Brain-Computer Interfaces (BCIs), capable of direct brain-to-computer communication but also effective in alleviating neurological impairments. The fusion of BCIs with Virtual Reality (VR) allowed the enhancement of the field of virtual rehabilitation by including patients with low-level of motor control with limited access to treatment. BCI-VR technology has pushed research towards finding new solutions for better and reliable BCI control. Based on our previous work, we have developed NeuRow, a novel multiplatform prototype that makes use of multimodal feedback in an immersive VR environment delivered through a state-of-the-art Head Mounted Display (HMD). In this article we present the system design and development, including important features for creating a closed neurofeedback loop in an implicit manner, and preliminary data on user performance and user acceptance of the system.
- The combined impact of virtual reality neurorehabilitation and its interfaces on upper extremity functional recovery in patients with chronic strokePublication . Cameirão, Mónica S.; Bermúdez i Badia, Sergi; Duarte, Esther; Frisoli, Antonio; Verschure, Paul F. M. J.Background and Purpose—Although there is strong evidence on the beneficial effects of virtual reality (VR)-based rehabilitation, it is not yet well understood how the different aspects of these systems affect recovery. Consequently, we do not exactly know what features of VR neurorehabilitation systems are decisive in conveying their beneficial effects. Methods—To specifically address this issue, we developed 3 different configurations of the same VR-based rehabilitation system, the Rehabilitation Gaming System, using 3 different interface technologies: vision-based tracking, haptics, and a passive exoskeleton. Forty-four patients with chronic stroke were randomly allocated to one of the configurations and used the system for 35 minutes a day for 5 days a week during 4 weeks. Results—Our results revealed significant within-subject improvements at most of the standard clinical evaluation scales for all groups. Specifically we observe that the beneficial effects of VR-based training are modulated by the use/nonuse of compensatory movement strategies and the specific sensorimotor contingencies presented to the user, that is, visual feedback versus combined visual haptic feedback. Conclusions—Our findings suggest that the beneficial effects of VR-based neurorehabilitation systems such as the Rehabilitation Gaming System for the treatment of chronic stroke depend on the specific interface systems used. These results have strong implications for the design of future VR rehabilitation strategies that aim at maximizing functional outcomes and their retention. Clinical Trial Registration—This trial was not registered because it is a small clinical study that evaluates the feasibility of prototype devices.
- Combining virtual reality and a myoelectric limb orthosis to restore active movement after stroke: a pilot studyPublication . Bermúdez i Badia, Sergi; Lewis, Ela; Bleakley, ScottWe introduce a novel rehabilitation technology for upper limb rehabilitation after stroke that combines a virtual reality (VR) training paradigm with a myoelectric robotic limb orthosis. Our rehabilitation system is based on clinical guidelines and is designed to recruit specific motor networks to promote neuronal reorganization. The main hypothesis is that the restoration of active movement facilitates the full engagement of motor control networks during motor training. By using a robotic limb orthosis, we are able to restore active arm movement in severely affected stroke patients. In a pilot evaluation, we have successfully deployed and assessed our system with three chronic stroke patients by means of behavioral data and self-report questionnaires. The results show that our system is able to restore up to 60% of the active movement capability of patients. Further, we show that we can assess the specific contribution of the biceps/triceps movement of the paretic arm in a VR bilateral training task. Questionnaire data show enjoyment and acceptance of the developed rehabilitation system and its VR training task.
- Eye gaze patterns after stroke: correlates of a VR action execution and observation taskPublication . Alves, Júlio; Vourvopoulos, Athanasios; Bernardino, Alexandre; Bermúdez i Badia, SergiThe concept of a partially shared neural circuitry between action observation and action execution in healthy participants has been demonstrated through a number of studies. However, little research has been done in this regard utilizing eye movement metrics in rehabilitation contexts.In this study we approach action observation and action execution by combining a virtual environment and eye tracking technology. Participants consisted of stroke survivors, and were required to perform a simple reachand-grab and place-and-release task with both their paretic and non-paretic arm. Results showed congruency in gaze metrics between action execution and action observation, for distribution and duration of gaze events. Furthermore, in action observation, longer smooth pursuit segments were detected when observing the representation of the paretic arm, thus providing evidence that the affected circuitry may be activated during observation of the simulated action. These results can lead to novel rehabilitation methods using virtual reality technology.
- Measured and perceived physical responses in multidimensional fitness training through exergames in older adultsPublication . Munoz, J. E.; Gonçalves, A.; Gouveia, E. R.; Cameirão, M. S.; Bermúdez i Badia, S.Exergames have been used to increase physical activity levels to produce health benefits in older adults. However, only a small number of studies have quantified the physical activity levels produced by custom-made Exergames and their capacity to elicit recommended levels of exercise. This study investigates the effectiveness of custom-made Exergames, designed for multidimensional fitness training, in eliciting recommended levels of exercise. We rely on both objective (accelerometry) and subjective (perceived exertion) information collected in two different modalities of exercise, consisting of 40- minutes sessions: Exergaming and conventional training (Control). A between-subjects analysis was done involving two groups of active older adults (n=33). Participants in the Control Between condition performed physical activity in conventional group fitness training, while the intervention group used individualized Exergaming as training modality. In addition, a sub-group of the Exergaming participants also performed a conventional training session (Control-Within), which enabled a within-subjects comparison. Results show that participants spent significantly more time in moderate-to-vigorous intensities during Exergaming, interestingly, perceiving significantly lower exertion levels. The between-subjects analysis only presented statistically significant differences for the perceived exertion scale. This study helps to unveil the impact of custom-made Exergames in physical activity levels during training when compared to conventional training for the older adult population.