Sensory substitution for space gloves and for space robots

Sensory substitution systems for space applications are described. Physical sensors replace missing human receptors and feed information to the interpretive centers of a different sense. The brain is plastic enough so that, with training, the subject localizes the input as if it were received through the missing receptors. Astronauts have difficulty feeling objects through space suit gloves because of their thickness and because of the 4.3 psi pressure difference. Miniature force sensors on the glove palm drive an electrotactile belt around the waist, thus augmenting the missing tactile sensation. A proposed teleoperator system with telepresence for a space robot would incorporate teleproprioception and a force sensor/electrotactile belt sensory substitution system for teletouch

How a plantar pressure-based, tongue-placed tactile biofeedback modifies postural control mechanisms during quiet standing

The purpose of the present study was to determine the effects of a plantar pressure-based, tongue-placed tactile biofeedback on postural control mechanisms during quiet standing. To this aim, sixteen young healthy adults were asked to stand as immobile as possible with their eyes closed in two conditions of No-biofeedback and Biofeedback. Centre of foot pressure (CoP) displacements, recorded using a force platform, were used to compute the horizontal displacements of the vertical projection the centre of gravity (CoGh) and those of the difference between the CoP and the vertical projection of the CoG (CoP-CoGv). Altogether, the present findings suggest that the main way the plantar pressure-based, tongue-placed tactile biofeedback improves postural control during quiet standing is via both a reduction of the correction thresholds and an increased efficiency of the corrective mechanism involving the CoGh displacements

Optics-less smart sensors and a possible mechanism of cutaneous vision in nature

Optics-less cutaneous (skin) vision is not rare among living organisms, though its mechanisms and capabilities have not been thoroughly investigated. This paper demonstrates, using methods from statistical parameter estimation theory and numerical simulations, that an array of bare sensors with a natural cosine-law angular sensitivity arranged on a flat or curved surface has the ability to perform imaging tasks without any optics at all. The working principle of this type of optics-less sensor and the model developed here for determining sensor performance may be used to shed light upon possible mechanisms and capabilities of cutaneous vision in nature

The length-tension diagrams of human oblique muscles in trochlear palsy and strabismus sursoadductorius

We determined the relation between length and tension in detached oblique muscles of 16 strabismus patients that underwent surgery, before and during contraction evoked by intravenous administration of succinylcholine. We frequently found a nonlinear relation between length and tension, unlike our previous findings in recti. In superior oblique palsies, the superior oblique was found, before injection of succinylcholine, to be stiff after elongation, and did not contract after injection of succinylcholine, while the ipsilateral inferior oblique contract after injection of succinylcholine, but with a higher spring constant than did usual. In 3 cases the superior oblique contracted vividly after administration of succinylcholine despite the presence of excyclotropia, stereopsis, torticollis (2 cases) and a hypertropia that increased in adduction, in downgaze, in adduction-and-downgaze and on ipsilateral head-tilt. The finding of a vividly contracting superior oblique is incompatible with the diagnosis of a complete superior oblique palsy. We conclude that some of the cases diagnosed as congenital superior oblique palsy, having a hypertropia increasing in adduction, in downgaze, in adduction-and-downgaze and on ipsilateral head-tilt, are in fact cases of unilateral strabismus sursoadductorius (upshoot in adduction), a non-paretic motility disorder

Algunes reflexions entorn de la conceptualització de la infància i adolescència en risc social a l'Estat espanyol

L'article realitza una aproximació a les interpretacions del concepte de risc social de la infancia per part de diversos autors d'àmbit estatal, tenint també en compte els marcs legals català i espanyol. Pretén aclarir quins són els criteris valoratius emprats, tant des de l'àmbit acadèmic com del professional, per interpretar les categoritzacions de la infància i l'adolescència en processos de dificultat i precarietat social. Des d'aquesta perspectiva, s'hi analitza l'estreta relació entre factors de risc, desemparament i marginació. S'hi rebutgen les interpretacions que responsabilitzen el propi menor de la desadaptació, i s'hi defensa la hipótesi de la necessitat d'una intervenció socioeducativa que treballi per una disminució dels factors de risc en el propi medi, mantenint el seu protagonisme en aquest procés.This article is an approach to the different acceptances of the concept social risk as well as the terms neglect and maladjustment, based on the reflections made by different authors and both statal and autonomous legal framework. It intends to clarify which are the criteria of values used in academic and professional ambits in order to understand the categoriesfound in the fields of childhood and adolescence in difficult and precarious conditions. The strong relation between risk factors, neglect and margination has been analysed from this point of view. In the same way the interpretations that hold the minor himself responsible for his maladjustment are rejected and the author defends the necessity of a socio-educational intervention, which reduces the risk factors in the child's environment, and the need of paying close attention to the child's main role in this process.El artículo realiza una aproximación a las interpretaciones del concepto de riesgo social de la infancia por parte de diversos autores de ámbito estatal, teniendo también en cuenta los marcos legales catalán y español. Pretende aclarar cuáles son los criterios valorativos utilizados, tanto desde el ámbito academico como profesional, para interpretar las categorizaciones de la infancia en procesos de dificultad y precariedad. Desde esta perspectiva, se analiza la estrecha relación entre factores de riesgo, desamparamiento y marginación. Se rechazan las interpretaciones que responsabilizan al propio menor de la desadaptación y se defiende la hipótesis de la necesidad de una intervención socioeducativa que trabaje para una disminución de los factores de riesgo en el propio medio, manteniendo su protagonismo en este proceso

Dissipation and spontaneous symmetry breaking in brain dynamics

We compare the predictions of the dissipative quantum model of brain with neurophysiological data collected from electroencephalograms resulting from high-density arrays fixed on the surfaces of primary sensory and limbic areas of trained rabbits and cats. Functional brain imaging in relation to behavior reveals the formation of coherent domains of synchronized neuronal oscillatory activity and phase transitions predicted by the dissipative model.Comment: Restyled, slight changes in title and abstract, updated bibliography, J. Phys. A: Math. Theor. Vol. 41 (2008) in prin

Controlling posture using a plantar pressure-based, tongue-placed tactile biofeedback system

The present paper introduces an original biofeedback system for improving human balance control, whose underlying principle consists in providing additional sensory information related to foot sole pressure distribution to the user through a tongue-placed tactile output device. To assess the effect of this biofeedback system on postural control during quiet standing, ten young healthy adults were asked to stand as immobile as possible with their eyes closed in two conditions of No-biofeedback and Biofeedback. Centre of foot pressure (CoP) displacements were recorded using a force platform. Results showed reduced CoP displacements in the Biofeedback relative to the No-biofeedback condition. The present findings evidenced the ability of the central nervous system to efficiently integrate an artificial plantar-based, tongue-placed tactile biofeedback for controlling control posture during quiet standing

A survey of assistive technologies and applications for blind users on mobile platforms: a review and foundation for research

This paper summarizes recent developments in audio and tactile feedback based assistive technologies targeting the blind community. Current technology allows applications to be efficiently distributed and run on mobile and handheld devices, even in cases where computational requirements are significant. As a result, electronic travel aids, navigational assistance modules, text-to-speech applications, as well as virtual audio displays which combine audio with haptic channels are becoming integrated into standard mobile devices. This trend, combined with the appearance of increasingly user- friendly interfaces and modes of interaction has opened a variety of new perspectives for the rehabilitation and training of users with visual impairments. The goal of this paper is to provide an overview of these developments based on recent advances in basic research and application development. Using this overview as a foundation, an agenda is outlined for future research in mobile interaction design with respect to users with special needs, as well as ultimately in relation to sensor-bridging applications in genera