Schwannomatosis of the Spinal Accessory Nerve: A Case Report.

Schwannomatosis is a distinct syndrome characterized by multiple peripheral nerve schwannomas that can be sporadic or familial in nature. Cases affecting the lower cranial nerves are infrequent. Here, the authors present a rare case of schwannomatosis affecting the left spinal accessory nerve. Upon genetic screening, an in-frame insertion at codon p.R177 of the Sox 10 gene was observed. There were no identifiable alterations in NF1, NF2, LZTR1, and SMARCB1. This case demonstrates a rare clinical presentation of schwannomatosis in addition to a genetic aberration that has not been previously reported in this disease context

Inter-Brain Synchronization during Social Interaction

During social interaction, both participants are continuously active, each modifying their own actions in response to the continuously changing actions of the partner. This continuous mutual adaptation results in interactional synchrony to which both members contribute. Freely exchanging the role of imitator and model is a well-framed example of interactional synchrony resulting from a mutual behavioral negotiation. How the participants' brain activity underlies this process is currently a question that hyperscanning recordings allow us to explore. In particular, it remains largely unknown to what extent oscillatory synchronization could emerge between two brains during social interaction. To explore this issue, 18 participants paired as 9 dyads were recorded with dual-video and dual-EEG setups while they were engaged in spontaneous imitation of hand movements. We measured interactional synchrony and the turn-taking between model and imitator. We discovered by the use of nonlinear techniques that states of interactional synchrony correlate with the emergence of an interbrain synchronizing network in the alpha-mu band between the right centroparietal regions. These regions have been suggested to play a pivotal role in social interaction. Here, they acted symmetrically as key functional hubs in the interindividual brainweb. Additionally, neural synchronization became asymmetrical in the higher frequency bands possibly reflecting a top-down modulation of the roles of model and imitator in the ongoing interaction

Peripheral Nerve Tumors in Neurofibromatosis 1, Neurofibromatosis 2, and Schwannomatosis

Neurofibromatosis was first described in the nineteenth century. At the time, Friederich Daniel Von Recklinghausen detailed two cases of multiple neurofibromas. Although reports of similar cases had been published before his, Von Recklinghausen is credited with the initial description in 1882, postulating that the tumors originated from nerve sheath and plexal connective tissue. Similarly, in 1822 John Henry Wishart described what is believed to be neurofibromatosis type 2; however, it was Harvey Cushing’s description of a case of bilateral vestibular schwannomas in 1916 that highlighted and increased awareness of the disease (albeit the original presentation was thought to be in the context of neurofibromatosis type 1). Since their original description, understanding of these neurocutaneous diseases has greatly expanded. Knowledge of the genotypic mutations and molecular mechanisms underlying the disease pathophysiology has resulted in natural history enlightenment and optimal treatment refinement. However, many aspects of neurofibromatosis have yet to be explained and remain active areas of investigation. In this chapter, clinical, radiological, and surgical considerations for peripheral nerve tumor management in the context of neurocutaneous disorders are reviewed. More specifically, clinical presentations, pathological and imaging findings, as well as management for neurofibromatosis type 1, type 2, and schwannomatosis are comprehensively discussed

Radiological data of brachial plexus avulsion injury associated spinal cord herniation (BPAI-SCH) and comparison to anterior thoracic spinal cord herniation (ATSCH).

Spinal cord herniation (SCH) is a rare cause of myelopathy. When reported, SCH has most commonly been described as occurring spontaneously in the thoracic spine, and being idiopathic in nature (anterior thoracic spinal cord herniation, ATSCH) [1-3]. Several theories have been proposed to explain its occurrence, including congenital, inflammatory, and traumatic etiologies alike [1-4]. Even more rarely, SCH has been described to occur in the cervical spine in association with brachial plexus avulsion injuries (BPAI-SCH). In our accompanying article, Late Cervical Spinal Cord Herniation Resulting from Post-Traumatic Brachial Plexus Avulsion Injury, two cases of BPAI-SCH are presented and discussed in the context of the reviewed literature [5]. Here, pertinent accompanying follow-up data was collected and is presented for the cases, including postoperative radiographic outcome imaging. Furthermore, a table is presented comparing and contrasting ATSCH to BPAI-SCH. Although the two phenomena have been previously grouped together, this table highlights ATSCH and BPAI-SCH as distinct entities; more specifically, BPAI-SCH is a separate, long-term complicating feature of BPAI. This supplementary data helps treating physicians by increasing awareness and knowledge of BPAI-SCH as a distinct entity from ATSCH and cause of delayed neurological deterioration

Phonological and visual processing deficits can dissociate in developmental dyslexia: Evidence from two case studies

International audienceThe present study describes two French teenagers with developmental reading and writing impairments whose performance was compared to that of chronological age and reading age matched non-dyslexic participants. Laurent conforms to the pattern of phonological dyslexia: he exhibits a poor performance in pseudo-word reading and spelling, produces phonologically inaccurate misspellings but reads most exception words accurately. Nicolas, in contrast, is poor in reading and spelling of exception words but is quite good at pseudo-word spelling, suggesting that he suffers from surface dyslexia and dysgraphia. The two participants were submitted to an extensive battery of metaphonological tasks and to two visual attentional tasks. Laurent demonstrated poor phonemic awareness skills but good visual processing abilities, while Nicolas showed the reverse pattern with severe difficulties in the visual attentional tasks but good phonemic awareness. The present results suggest that a visual attentional disorder might be found to be associated with the pattern of developmental surface dyslexia. The present findings further show that phonological and visual processing deficits can dissociate in developmental dyslexia

Démarche de pratique réflexive au collégial dans l'enseignement de la philosophie et du français, langue d'enseignement et littérature

"La présente recherche a été subventionnée par le ministère de l'Éducation, du Loisir et du Sport dans le cadre du Programme d'aide à la recherche sur l'enseignement et l'apprentissage (PAREA)"Titre de l'écran-titre (visionné le 12 nov. 2008).Également disponible en format papier.Médiagraphi

Tumeur pancréatique rare de découverte fortuite chez un enfant en Côte d’Ivoire

La tumeur pseudo-papillaire et solide du pancréas (TPPSP) est une tumeur rare. Elle touche le plus souvent la femme jeune. Décrite la première fois par Frantz en 1959, sa pathogénie demeure peu claire. C’est une tumeur de bon pronostic qui nécessite une chirurgie radicale. Les auteurs rapportent un cas de TPPSP chez une fillette de 11 ans. La symptomatologie était aiguë, faite de syndrome de compression et d’épigastralgies. L’examen trouvait une masse solide de l’hypochondre gauche. Le scanner montrait une masse de structure mixte de la queue du pancréas. Une splénopancréatectomie gauche était réalisée. Le diagnostic était confirmé par l’examen histologique avec immunohistochimie. Le suivi à long terme ne montrait pas de récidive. Le recul est de deux ans et demi. À travers cette observation et une revue de la littérature, les auteurs discutent la contribution de la radiologie dans le diagnostic et insistent sur une chirurgie radicale dans le traitement de ces tumeurs de faible degré de malignité

Classification methods for ongoing EEG and MEG signals

Classification algorithms help predict the qualitative properties of a subject's mental state by extracting useful information from the highly multivariate non-invasive recordings of his brain activity. In particular, applying them to Magneto-encephalography (MEG) and electro-encephalography (EEG) is a challenging and promising task with prominent practical applications to e.g. Brain Computer Interface (BCI). In this paper, we first review the principles of the major classification techniques and discuss their application to MEG and EEG data classification. Next, we investigate the behavior of classification methods using real data recorded during a MEG visuomotor experiment. In particular, we study the influence of the classification algorithm, of the quantitative functional variables used in this classifier, and of the validation method. In addition, our findings suggest that by investigating the distribution of classifier coefficients, it is possible to infer knowledge and construct functional interpretations of the underlying neural mechanisms of the performed tasks. Finally, the promising results reported here (up to 97% classification accuracy on 1-second time windows) reflect the considerable potential of MEG for the continuous classification of mental state