26 research outputs found
Les discours associatifs autour de l'autisme en ligne : entre conflictualité et institutionnalisation
In France, the public discourse on autism is almost solely carried by parent-led organizations. However, they are now confronted with the arising discourses of autistic-led organizations. This thesis aims to answer the following question: what are the characteristics of the discourses held by French associations focusing on autism on their websites? This work analyses the enunciation of eight french organizations from a perspective of Discourse Analysis. Beyond the common features bringing together those organizations together within one discursive formation, this work highlights some significant differences between the discourses held by those two groups. Thus, if the discourses of autistic-led organizations are militant and polyphonic, we observe the beginning of an institutionalization of the speeches held by parent-led organizations. This process led the latter to conceal the dissensions existing between them, autistic-led organizations and psychoanalysis. This work thus highlights an important transformation in the french public discourse held on autism in recent years.En France, la parole publique sur l’autisme est presque exclusivement portée par des associations de familles. Cependant, elles se trouvent aujourd’hui confrontées aux discours de nouveaux acteurs émergents, les associations dirigées par des personnes elles-mêmes autistes. Ce mémoire s’attache à identifier les caractéristiques des différents discours que tiennent les associations relatives à l’autisme sur leurs sites web officiels. Il s’intéresse à huit associations françaises en utilisant des outils issus de l’Analyse de discours. Au-delà des points communs qui les réunissent au sein d’une même formation discursive, il met en évidence d’importantes différences entre les discours de ces groupes pourtant proches. Ainsi, si les associations de personnes autistes produisent des discours militants et polyphoniques, on constate le début d’une institutionnalisation des discours des associations de familles, qui se traduit par l’effacement des dissensions existant entre elles, les associations de personnes autistes et la psychanalyse. Ce travail de mémoire vient donc souligner une transformation importante du discours public tenu sur l’autisme au cours de ces dernières années
Development of Biosignal Recording Board System with Agile Control of Circuit Characteristics for Various Biosignals
L'instrumentation d'imagerie medicale tridimentionnelle au LETI
communication to : 29. Meeting of the French Society of Hospital Physicists, Lille (FR), 7-9 June 1991SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : RM 1626 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc
WIMAGINE: Wireless 64-Channel ECoG Recording Implant for Long Term Clinical Applications
International audienc
A Long-Term BCI Study With ECoG Recordings in Freely Moving Rats
International audienceBackgroundBrain Computer Interface (BCI) studies are performed in an increasing number of applications. Questions are raised about electrodes, data processing and effectors. Experiments are needed to solve these issues. ObjectiveTo develop a simple BCI set-up to easier studies for improving the mathematical tools to process the ECoG to control an effector. MethodWe designed a simple BCI using transcranial electrodes (17 screws, three mechanically linked to create a common reference, 14 used as recording electrodes) to record Electro-Cortico-Graphic (ECoG) neuronal activities in rodents. The data processing is based on an online self-paced non-supervised (asynchronous) BCI paradigm. N-way partial least squares algorithm together with Continuous Wavelet Transformation of ECoG recordings detect signatures related to motor activities. Signature detection in freely moving rats may activate external effectors during a behavioral task, which involved pushing a lever to obtain a reward. ResultsAfter routine training, we showed that peak brain activity preceding a lever push (LP) to obtain food reward was located mostly in the cerebellar cortex with a higher correlation coefficient, suggesting a strong postural component and also in the occipital cerebral cortex. Analysis of brain activities provided a stable signature in the high gamma band (approximate to 180Hz) occurring within 1500 msec before the lever push approximately around -400 msec to -500 msec. Detection of the signature from a single cerebellar cortical electrode triggers the effector with high efficiency (68% Offline and 30% Online) and rare false positives per minute in sessions about 30 minutes and up to one hour (approximate to 2 online and offline). ConclusionsIn summary, our results are original as compared to the rest of the literature, which involves rarely rodents, a simple BCI set-up has been developed in rats, the data show for the first time long-term, up to one year, unsupervised online control of an effector
WIMAGINE<sup>®</sup>: 64-channel ECoG recording implant for human applications
International audienc
Deep brain stimulation: BCI at large, where are we going to?
Brain-computer interfaces (BCIs) include stimulators, infusion devices, and neuroprostheses. They all belong to functional neurosurgery. Deep brain stimulators (DBS) are widely used for therapy and are in need of innovative evolutions. Robotized exoskeletons require BCIs able to drive up to 26 degrees of freedom (DoF). We report the nanomicrotechnology development of prototypes for new 3D DBS and for motor neuroprostheses. For this complex project, all compounds have been designed and are being tested. Experiments were performed in rats and primates for proof of concepts and development of the electroencephalogram (EEG) recognition algorithm
Long-term sheep implantation of WIMAGINE®, a Wireless 64-channel electrocorticogram recorder
International audienceThis article deals with the long-term preclinical validation of WIMAGINE® (Wireless Implantable Multi-channel Acquisition system for Generic Interface with Neurons), a 64-channel wireless implantable recorder that measures the electrical activity at the cortical surface (electrocorticography, ECoG). The WIMAGINE® implant was designed for chronic wireless neuronal signal acquisition, to be used e.g., as an intracranial Brain–Computer Interface (BCI) for severely motor-impaired patients. Due to the size and shape of WIMAGINE®, sheep appeared to be the best animal model on which to carry out long-term in vivo validation. The devices were implanted in two sheep for a follow-up period of 10 months, including idle state cortical recordings and Somato-Sensory Evoked Potential (SSEP) sessions. ECoG and SSEP demonstrated relatively stable behavior during the 10-month observation period. Information recorded from the SensoriMotor Cortex (SMC) showed an SSEP phase reversal, indicating the cortical site of the sensorimotor activity was retained after 10 months of contact. Based on weekly recordings of raw ECoG signals, the effective bandwidth was in the range of 230 Hz for both animals and remarkably stable over time, meaning preservation of the high frequency bands valuable for decoding of the brain activity using BCIs. The power spectral density (in dB/Hz), on a log scale, was of the order of 2.2, –4.5 and –18 for the frequency bands (10–40), (40–100), and (100–200) Hz, respectively. The outcome of this preclinical work is the first long-term in vivo validation of the WIMAGINE® implant, highlighting its ability to record the brain electrical activity through the dura mater and to send wireless digitized data to the external base station. Apart from local adhesion of the dura to the skull, the neurosurgeon did not face any difficulty in the implantation of the WIMAGINE® device and post-mortem analysis of the brain revealed no side effect related to the implantation. We also report on the reliability of the system; including the implantable device, the antennas module and the external base station
MIRME : microsystèmes en IRM endoluminale appliqués au diagnostic pour le traitement des pathologies cardiovasculaires et digestives
International audienc