Modulation of pain threshold by virtual body ownership

Background Appropriate sensorimotor correlations can result in the illusion of ownership of exogenous body parts. Nevertheless, whether and how the illusion of owning a new body part affects human perception, and in particular pain detection, is still poorly investigated. Recent findings have shown that seeing one’s own body is analgesic, but it is not known whether this effect is transferable to newly embodied, but exogenous, body parts. In recent years, results from our laboratory have demonstrated that a virtual body can be felt as one’s own, provided realistic multisensory correlations. Methods The current work aimed at investigating the impact of virtual body ownership on pain threshold. An immersive virtual environment allowed a first-person perspective of a virtual body that replaced the own. Passive movement of the index finger congruent with the movement of the virtual index finger was used in the “synchronous” condition to induce ownership of the virtual arm. The pain threshold was tested by thermal stimulation under four conditions: 1) synchronous movements of the real and virtual fingers, 2) asynchronous movements, 3) seeing a virtual object instead of an arm, and 4) not seeing any limb in real world. Results Our results show that, independently of attentional and stimulus adaptation processes, the ownership of a virtual arm per se can significantly increase the thermal pain threshold. Conclusions This finding may be relevant for the development and improvement of digital solutions for rehabilitation and pain treatment.

Mathematica in the classroom: new tools for exploring precalculus and differential calculus

Prémio de Melhor Artigo de Jovem Investigador atribuído pela empresa Timberlake, apresentado na 1ª Conferência Nacional sobre Computação Simbólica no Ensino e na Investigação - CSEI2012, que decorreu no IST nos dias 2 e 3 de Abril.

Controlled study of 50-Hz repetitive transcranial magnetic stimulation for the treatment of Parkinson disease.

OBJECTIVE: To investigate the safety and efficacy of 50-Hz repetitive transcranial magnetic stimulation (rTMS) in the treatment of motor symptoms in Parkinson disease (PD). BACKGROUND: Progression of PD is characterized by the emergence of motor deficits that gradually respond less to dopaminergic therapy. rTMS has shown promising results in improving gait, a major cause of disability, and may provide a therapeutic alternative. Prior controlled studies suggest that an increase in stimulation frequency might enhance therapeutic efficacy. METHODS: In this randomized, double blind, sham-controlled study, the authors investigated the safety and efficacy of 50-Hz rTMS of the motor cortices in 8 sessions over 2 weeks. Assessment of safety and clinical efficacy over a 1-month period included timed tests of gait and bradykinesia, Unified Parkinson's Disease Rating Scale (UPDRS), and additional clinical, neurophysiological, and neuropsychological parameters. In addition, the safety of 50-Hz rTMS was tested with electromyography-electroencephalogram (EMG-EEG) monitoring during and after stimulation. RESULTS: The authors investigated 26 patients with mild to moderate PD: 13 received 50-Hz rTMS and 13 sham stimulation. The 50-Hz rTMS did not improve gait, bradykinesia, and global and motor UPDRS, but there appeared a short-lived "on"-state improvement in activities of daily living (UPDRS II). The 50-Hz rTMS lengthened the cortical silent period, but other neurophysiological and neuropsychological measures remained unchanged. EMG/EEG recorded no pathological increase of cortical excitability or epileptic activity. There were no adverse effects. CONCLUSION: It appears that 50-Hz rTMS of the motor cortices is safe, but it fails to improve motor performance and functional status in PD. Prolonged stimulation or other techniques with rTMS might be more efficacious but need to be established in future research.

Histología de folículos post-ovulatorios de la sardina (Sardinops sagax) del Perú

El siguiente estudio se basa en la utilización de folículos post-ovulatorios como medio de estimación de desove. En este caso se abarcan los días 0, 1 y 2.

Captación de larvas de moluscos en Bahía de Paracas, Perú

Entre enero y mayo de 1986 100 colectores de larvas fueron instaldas en Bahía Paracas (13º50' S, 76º16' W) en áreas de cultivo de la concha de abanico Argopecten purpuratus con el fin de obtener semillas de bivalvos de valor económico. Mayormente con el objetivo de determinar el mejor tiempo para la instalación de los colectores entre enero de 1985 y agosto de 1986 se efectuaron determinaciones mensuales de factores abióticos (temperatura, salinidad, oxígeno, H1S) de las aguas cerca del fondo del mar, la concentración de clorofila "a" y del índice gonadosomático de adultos de A.purpuratus, además de análisis cualitativos de muestras del plancton. Las especies dominantes en número de individuos encontradas en los 82 colectores recuperados después de dos meses de exposición fueron el falso chorito Semimytilus algosus (70 %) y la almejita blanca Petricola sp. (27 %), ambas especies de valor económico. Solo de 0.8 % de la semilla era A. purpuratus, lo que se atribuyó mayormente al material inadecuado usado para los colectores, pero también a mareas rojas que ocurrieron durante el tiempo del experimento.

L'Écho de Paris

1887/03/25 (Numéro 1105).

L'Écho de Paris

1887/01/19 (Numéro 1040).

Breviarium Arelatense.

F. 1-19 Hymnaire : — Annonciation (M. G., Poet. lat., IV, 660-661, ms. B de Strecker) (8). F. 19v Capitules. F. 33 Oraisons du temporal, du sanctoral, du commun des saints, des féries. F. 67 « Preces », bénédictions à matines. F. 70-263v Antiennes, leçons et répons du temporal et du sanctoral : — s. Trophime ; cf. Gazay, dans Ann. du Midi, 1913, 19 (199) ; — « Vita b. Bardulphi » (240v) ; — s. Nicolas (262) (incompl. de la fin).

Inventaire des lettres d'anoblissement, de légitimation et de naturalité, enregistrées à la chambre des comptes de 1349 à 1655.

Contient : a Acte, en latin, du roi CHARLES VIII. Le roi y anoblit Éloi Gigaud et sa postérité. Éloi Gigaud est dit demeurer « in parrochia de Mehers, prope Castriam, in provincia Bituriae ». Plessis lez Tours, mai 1489 ; b Note concernant la famille Nicolay, de 1440 à 1588, où l'on examine à quelle date la qualité de noble à été donnée à Jean Nicolay, père du premier Nicolay qui fut « premier president aux comptes à Paris ». On a joint à cette note la copie de trois actes, en latin, des années 1452, 1469, 1522. Jean Nicolay figure dans les deux premiers, et son fils, le premier président, dans le troisième ; c Acte par lequel le roi LOUIS XIV déclare légitimés ses enfants naturels Louis-Auguste, duc du Maine, Louis-César, comte du Vexin, Louise-Françoise de Nantes. St-Germain-en-Laye, décembre 1673 ; d Le « lieu de Mouchy le Vieil », donné à « Jean, bastard de Tyen, bailly de Senlis, au mois de juin 1422 » ; e « Me Jean Bruslard,... ordonné avocat... du roy en la prevosté de Chastillon sur Marne, par lettres du roy du 28 fevrier 1423 » ; f La famille de Jeanne d'Arc. 1429 et 1473 ; g Un mandement du roi Louis XI « au seigneur de La Roche-Guyon », pour « laisser passer 60 tonneaux de vin », envoyés par ledit roi au roi d'Angleterre, Henri VI. Paris, 16 nov. 1470