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---------------------------------------------------------------Alejandro Gustavo Sabatini

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------------------------ver PARADIGMAS DE LA INTERACCIÓN en el archivo 2.A.0.-Paradigmas de la Interaccion
---------------------------------ver estudio de Interfaces en el archivo 2.A.1.1.2.7.-Interaccion - Interface en Realidad Virtual
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El AlloSphere es un espacio esférico en el que inmersivos entornos virtuales permiten a los investigadores convertir grandes conjuntos
de datos en las experiencias de la vista y el sonido. Por ejemplo, permite a los investigadores "volar" a través de un átomo de hidrógeno,
mientras que la audición sonido de campo tiene las características de la función de onda de su único electrón para ayudar a describir
los procesos invisibles de la naturaleza.

La instalación consiste en una esfera de 30-pies de diámetro construido dentro de un cubo de 3-historia que es casi libre de eco. Dentro
de la cámara son dos hemisferios esférica que están fabricados en aluminio microperforado para que pueda ser ópticamente opacos y
acústicamente transparente. A 7 metros de ancho puente cruza el centro con el apoyo a los usuarios. Proyectores de vídeo de alta
resolución puede proyectar imágenes a través de toda la superficie interna transparente que permite la proyección estéreo 3D óptica.

Ver video en la siguiente URL http://www.allosphere.ucsb.edu/


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TENDENCIAS TECNOLÓGICAS

Crean un dispositivo de realidad virtual que estimula los cinco sentidos

Científicos del Reino Unido acaban de presentar el prototipo del primer dispositivo de realidad virtual de la historia que estimulará
los cinco sentidos, y no sólo la vista y el oído. Los investigadores esperan que este sistema, que aún está en fase de desarrollo,
llegue a ser más barato y llevadero que los actualmente existentes. Sus posibles aplicaciones van desde viajar a lugares remotos
sin necesidad de moverse de casa y con un realismo total, hasta ayudar a los médicos a operar a pacientes que estén en otros
lugares del mundo. Asimismo, los investigadores pretenden evaluar el impacto que en la sociedad tendría el hecho de que
pudiéramos sumergirnos en la realidad virtual con el mismo realismo con que lo hacemos en el mundo.





http://www.newscientist.com/article/dn16794-ultimate-virtual-reality-will-trigger-five-senses.html?DCMP=OTC-rss&nsref=online-news

Imagine a virtual experience that you can't distinguish from reality. Researchers from the University of York and the University of Warwick, both UK, are working on plans for a device able to manipulate five of a person's senses, to given them the sensation of being somewhere else. But while systems to control what a person sees and hears are well-established, touch, smell and taste are much harder to control realistically. The video above shows how the team intend to do that, for example by capturing smells from the real world to be "played back" later. However, they warn that a working prototype is still at least 15 to 20 years away

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Una sencilla técnica consigue hacer creer a la gente que está en otro cuerpo:

La manipulación de la perspectiva visual y multisensorial genera la ilusión de que el cuerpo ajeno es el propio

La percepción del cuerpo como estancia de nuestra conciencia responde a la integración continua de señales multisensoriales y motoras en marcos de referencia ego-céntricos, explican científicos del Karolinska Insitutet de Suecia (KI). Sin embargo, experimentos realizados han demostrado que estos marcos de referencia pueden variar si se usan “trampas” perceptivas. El resultado de diversos experimentos realizados en el KI ha sido soprendente: cualquier persona puede sentir que se encuentra en el cuerpo de otro, bien quieto, bien realizando un acto voluntario. La ilusión tendría aplicaciones en varios campos, sobre todo en el de la realidad virtual, donde aumentaría el realismo.



La idea de que un individuo cambie su cuerpo por el de otra persona ha estado en la imaginación de escritores y artistas durante décadas. Esta idea es reflejo de una pregunta fundamental: ¿por qué experimentamos la certeza de que nos encontramos dentro de nuestro organismo?

Ahora, un equipo de neurocientíficos cognitivos del Karolinska Institutet (KI) , una universidad médica de Suecia, ha conseguido que la gente perciba los cuerpos de maniquíes y de otras personas como si fueran el suyo propio.

Tal y como han explicado los investigadores en un artículo aparecido en la revista PlosOne Artículo PloSOne, la manipulación de la perspectiva visual, en combinación con la recepción de información multisensorial, fue suficiente para generar la ilusión de que un cuerpo ajeno podía ser el propio.

Compartiendo la visión

En un comunicado publicado por el KI, se explica que fueron realizados varios experimentos distintos.

En uno de ellos, se adaptaron dos cámaras a la cabeza de un maniquí de tienda. Estas cámaras estaban conectadas a dos pequeñas pantallas, que a su vez fueron situadas en frente de los ojos de una persona. De esta manera, dicha persona podía ver lo que “veía” el maniquí.

Cuando los ojos-cámara del muñeco y la cabeza de la persona eran dirigidos hacia abajo, el sujeto veía el cuerpo del maniquí en el mismo lugar en el que, normalmente, veía el suyo propio.

La ilusión del “cuerpo cambiado” se creó cuando los científicos tocaron el estómago de la persona y también el del maniquí con sendas varillas al mismo tiempo. Entonces, el sujeto pudo ver que el estómago del maniquí estaba siendo tocado, al tiempo que sentía (sin verlo) que también le estaban tocando su propio estómago.

Como resultado, el participante humano informó de haber tenido la sensación de que el cuerpo del maniquí era su propio cuerpo.

Cuestión de impresiones sensoriales

Según declaraciones del investigador Henrik Ehrsson, director del proyecto, estos resultados demuestran lo fácil que es cambiar la percepción cerebral de la identidad física.

Sólo con manipular las impresiones sensoriales, es posible hacer creer a una persona no sólo que está fuera de su propio cuerpo, sino también que está en otros cuerpos.

En otro de los experimento, las cámaras fueron colocadas en la cabeza de dos personas, en lugar de en un maniquí. Cuando ambos participantes (que tenían ante sus ojos las pantallas que reflejaban lo que la otra persona veía), se miraron el uno al otro para saludarse dándose la mano, en realidad lo que veían enfrente eran sus propios cuerpos.

Sin embargo, según los científicos, en este caso, estos voluntarios experimentaban la visión de sí mismos dándose la mano desde el exterior como si fuera otra persona la que se les acercaba.

En este caso, la impresión sensorial generó que sintieran que la persona que venía a saludarles era “otro cuerpo”, en lugar de verse a sí mismos.

No podemos identificarnos con objetos

En otro de los experimentos realizados, tal y como explica el artículo de PlosOne, se utilizaron un maniquí y un objeto rectangular para saber si el individuo podía “creer” que era cualquier forma física.

Los resultados demostraron que había grandes diferencias en el nivel de respuesta de los participantes entre una y otra forma. Es decir, que las personas sólo pueden experimentar como propios –aunque no lo sean- cuerpos similares al suyo o de apariencia humana, señalan los investigadores.

Pero, dentro de este límite, la ilusión funciona cuando las personas difieren mucho físicamente, e incluso cuando son de sexos opuestos.

Según los científicos, estos resultados demuestran que las personas podemos percibir el cuerpo de otros, o un cuerpo artificial, como propio. Y que esto ocurre tanto cuando los participantes no se mueven como cuando están ejecutando un movimiento voluntario (darse la mano).


Trampas perceptivas y aplicaciones

Las condiciones necesarias para que se produzca esta ilusión perceptiva serían un acople continuo entre la información visual y la información somatosensorial sobre el estado del cuerpo; el uso de un cuerpo “alternativo” de apariencia suficientemente humanoide y, por último, la adopción de la perspectiva visual de dicho cuerpo alternativo.

Los resultados obtenidos con estos experimentos suministrarían un nuevo método de traslación del centro de conciencia percibido por las personas de un cuerpo a otro, lo que tendría importantes aplicaciones científicas, industriales y clínicas, aseguran los investigadores.

En la psicología social, por ejemplo, podría servir como herramienta de investigación de los desórdenes de percepción de la propia imagen física. En la realidad virtual, por otra parte, las aplicaciones de este experimento podrían aumentar la capacidad de control del usuario, la sensación de realismo y el sentimiento de “presencia” dentro de dicha realidad alternativa.

En definitva, los experimentos han demostrado lo fácil que es “mover” el centro de conciencia del ser humano de un cuerpo a otro. La cuestión sobre la relación entre nuestra conciencia y el cuerpo es antigua y ha sido discutida desde siempre por filósofos, psicólogos y teólogos.

La integración continua de señales multisensoriales y motoras en marcos de referencia ego-céntricos mantendrían el co-alienamiento entre la experiencia del yo y el cuerpo físico. Pero este acoplamiento perfecto puede modificarse haciendo “trampas” perceptivas.
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If I Were You: Perceptual Illusion of Body Swapping
Valeria I. Petkova*, H. Henrik Ehrsson Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden Abstract The concept of an individual swapping his or her body with that of another person has captured the imagination of writers and artists for decades. Although this topic has not been the subject of investigation in science, it exemplifies the fundamental question of why we have an ongoing experience of being located inside our bodies. Here we report a perceptual illusion of body-swapping that addresses directly this issue. Manipulation of the visual perspective, in combination with the receipt of correlated multisensory information from the body was sufficient to trigger the illusion that another person's body or an artificial body was one's own. This effect was so strong that people could experience being in another person's body when facing their own body and shaking hands with it. Our results are of fundamental importance because they identify the perceptual processes that produce the feeling of ownership of one's body.
Introduction We all experience our body to be part of ourselves. The question of how this comes about has been discussed by philosophers and psychologists for centuries [1], [2], [3], [4]. Recent advances in experimental science have made it possible for cognitive neuroscientists to begin to investigate how we perceive our body as an object distinct from the external world [2], [5], [6], [7], [8]. Having the experience of being the owner of one's body is clearly adaptive, and its function probably relates to the problem of localising and correctly identifying oneself in the sensory environment [9], [10], a problem faced by all central nervous systems [11]. Consider a fight between two or more individuals. Survival depends on rapid identification and accurate localisation of one's own body. From neurology we know that these functions can break down as people with pathological conditions affecting frontal and parietal lobes can sometimes fail to recognise their limbs as belonging to themselves [12], [13], [14]. Similarly, damage to, or abnormal physiology of, frontal, parietal and temporal regions can be associated with feelings of being outside the body [15], [16]. Although these neurological observations suggest that certain brain regions might be responsible for generating the habitual experience of being located within one's body and of owning it, they tell us little about the underlying processes. If we want to understand why our centre of awareness, or sense of ‘self’, is located inside our body, illusions of bodily self-perception could be invaluable. The study of illusions is a classical approach adopted in psychology to learn more about the basic processes that underlie normal perception. Indeed, some important initial insights into the mechanisms underlying self-perception of one's own body have been gained through illusions. One such is the so called ‘Rubber Hand Illusion’ where people have the experience that a prosthetic hand is actually their own hand [17]. In this illusion, synchronous touches applied to a rubber hand in full view of the participant, and the real hand, which is hidden behind a screen, produce the sensations that the touch originates from the rubber hand and a feeling of ownership of the artificial hand. This suggests that the temporal and spatial patterns of visual and somatosensory signals play an important role in how we come to experience that a limb is part of our own body [5], [7], [18], [19]. Another important factor in determining how we perceive our own body is the adoption of the first person perspective [6], [20]. When we look at ourselves directly, our limbs and body always present themselves in certain orientations because our eyes are fixed to our skull. By changing the visual perspective, it is possible to induce the feeling of being in a different place [21], [22], [23] or, even, illusory ‘out-of-body experiences’ where people seem to lose ownership of their own body when observing it from the point of view of another person (which we refer to as the third person perspective) [6]. On the basis of this previous knowledge, we hypothesized that it would be possible to induce illusions of owning an entire body other than one's own by the experimental manipulation of the visual perspective in conjunction with correlated visual and sensory signals being supplied to the respondent's body. Our experiments reveal that healthy volunteers can indeed experience other people's bodies, as well as artificial bodies, as being their own. This effect is so robust that, while experiencing being in another person's body, a participant can face his or her biological body and shake hands with it without breaking the illusion. The existence of this illusion (and the identification of the factors triggering it) represents a major advance because it informs us about the processes that make us feel that we own our body in its entirety.
Discussion: The results of our experiments demonstrate that healthy volunteers can perceive another person's body, or an artificial humanoid body, to be their own. This works both when the participant does not move and when he or she is executing voluntary movements. The critical conditions for eliciting this perceptual illusion are: (i) a continuous match between visual and somatosensory information about the state of the body; (ii) the usage of a sufficiently humanoid body; and (iii) the adoption of a first person visual perspective of the body. Particularly strong evidence for this was the counter-intuitive demonstration that one can face one's physical body and shake hands with it whilst experiencing the illusion of being within another person's body. These findings are of fundamental importance because they identify the perceptual processes that make us feel that we own our entire body. Our results also provide a new method to move a person's perceived centre of awareness from one body to another, which could have important scientific, industrial and clinical applications (as will be discussed below). Objective evidence for the illusion of owning an entire body was obtained by demonstrating that physical threats to the ‘new’ body elicited increased sweating (skin conductance responses) when people experienced the illusion. Similarly, threats to the ‘new body’ evoked greater skin conductance responses than threats to the ‘old’ physical one during the illusory body swapping. The SCR elicited by physical threats is a particularly good objective measure of body ownership. Emotional defence reactions, such as fear and autonomic arousal, have emerged in the course of evolution to enable one to protect one's own body from physical damage [26], [27]. The causal chain between threat-evoked SCR and the feeling of body ownership has been clarified in earlier work. There is a direct linear relationship between the strength of ownership of a hand and the degree of anxiety experienced when the hand is being subjected to physical threats [25]. This relationship is mirrored by the activity in multisensory areas, related to ownership, and areas in the emotional system, related to anxiety and pain anticipation [25]. The SCR is the peripheral correlate of activity in brain structures related to emotions, and is, therefore, greater when an owned rubber hand is physically injured than when it is not experienced as part of one's body [24]. Thus the differences in threat-evoked SCR that we observed in response to our experimental manipulations reflected the perceptual illusion of owning an entire body. The design of our experiments, employing multiple control conditions, ruled out potentially confounding factors such as attention to unexpected sensory events, the emotional salience of the stimuli presented, or associative learning (see Results for details). The central relevance of the present findings is that they inform us about how we come to experience that we own our bodies and why we have an on-going feeling of being located inside them (sometimes called ‘embodiment’ [28]). In the present illusions, the visual, tactile, proprioceptive information and the predicted sensory feedback from these modalities during active movements were temporally and spatially congruent in an ego-centric reference frame centred on a new body. Thus, the matching of multisensory and motor signals from the first person perspective is sufficient to create a full sense of ownership of one's own entire body. This conclusion certainly contrasts with the traditional text-book wisdom which emphasises that body perception is a direct result of bottom-up processing of afferent signals from muscles, joints and skin. Earlier work on body ownership has exclusively studied a single limb, the arm, using the traditional rubber hand illusion. Thus, until now, it was not known whether the principles underlying changes in ownership would generalise to other body parts, or to an entire body. Many multisensory brain areas seem to have particularly large representations of the hands and upper limbs [29], [30], and visual information is particularly important for guiding human hand actions [31], [32], [33], [34] and localising the arms in space [35]. The present data show that correlations of visual and tactile signals coming to a single body part (the abdomen or a hand) are sufficient to cause a feeling of ownership of the entire body (referred to as ‘whole-body ownership’). Thus the effect of correlated visual and tactile events on one limb generalises to non-stimulated body parts. This implies that visual and somatosensory signals from different body parts are analysed and interpreted together, i.e. that there are inter-dependences between the multisensory integration of different body parts. The central body representation is a ‘map of connected nodes’ where limbs and body segments form a continuous whole. It is this structure of the body representation coupled with the fact that the perceptual systems tend to produce single resolutions when resolving sensory conflicts [36], [37], [38] that makes whole-body illusions possible. The feeling of ownership of an entire body is , therefore, the result of a consistent pattern of spatially and temporally congruent multisensory signals from all body parts and the integration of this information in ego-centric reference frames centred on the various limbs and segments (that is, arm-centred, head-centred, etc). Our data also directly demonstrate that visual information from the first person perspective is critical for the experience of owning a body. In our ‘body swap’ experiment (Experiment #5) there was a direct conflict between the perspective seen from the new body and the sight of the real body observed from a third person perspective. The synchronized movements of the two people squeezing each other's hands did not provide evidence in favour of either body being one's own, so the critical determinant for ownership in this set-up was the visual perspective. The first person perspective was clearly dominant since most participants experienced being in the new body. This dominance of the first person perspective probably explains why people did not show a very strong response when their actual body was threatened in the asynchronous condition. The incongruent tactile and muscular information in the asynchronous condition led to a decrease in the strength of the illusion, but could not completely abolish it, as reported by many participants. Importantly, the effect of varying the timing of the seen and the felt hand movements was significant only from the first-person perspective. The reason for this probably relates to the fact that central processing of multisensory signals from the body operates in egocentric reference frames [18], [30], [32], [39], [40], [41], [42], [43] which presupposes the first person perspective. But why is bodily perception so malleable? The function of body ownership is probably related to the problem of localizing and correctly identifying the body in space. In this process, speed and accuracy are of utmost importance. According to recent statistical models of perception, the interpretation of multisensory signals could be sped up and made more precise by incorporating memory information (‘priors’) in the decision process [44], [45], [46]. In this framework, the body-swap illusions would arise as a result of the brain's tendency to rely heavily on a lifetime of experiences of seeing the world from the first person perspective with eyes that are fixed at a specific position on the skull, and the fact that the body typically produces certain patterns of sensory signals from the different modalities. Thus it is likely that the multisensory mechanisms involved in producing the present illusions are continuously engaged to refine the central estimate of the location of one's own body in natural situations. This implies that, in the experiments reported here, the spatial dimensions experienced as being occupied by one's own body, and the co-localisation of this sensed body and the physical body, are produced by this perceptual integration mechanism. This would explain why we have an on-going experience of being located inside our bodies. The present illusions are consistent with the physiological and anatomical organisation of the multisensory brain. It is possible that bimodal and multimodal cells in premotor and posterior parietal areas could play important roles by mediating critical multisensory integration [7], [41], [42], [43], [47]. These areas are part of a system that controls actions and they contain many neurons that integrate visual, tactile and proprioceptive information in head and body-part centred reference frames [7], [41], [42], [43], [47]. Furthermore, these multisensory cells are sensitive to the temporal and spatial congruency of multisensory signals [47]. Thus, this neuronal system has the capacity to perform the binding of visual, tactile, proprioceptive and motor signals in ego-centric coordinate systems centred on the new body. The sensory experience of one's own body from the first person perspective is different from recognising oneself in mirrors, TV screens or other image representations as observed from a third person perspective. When we recognise ourselves in a mirror, for example, we do not have the experience that we are actually in the mirror, or that there has been a change in ownership of our body. It is therefore likely that the present illusions involve different processes than those probed in earlier experiments on self-recognition in mirrors [48] or self-recognition of bodies [8], [49] and body parts observed from a third person perspective. A key difference probably is that, in the body-swap illusions, the visual, tactile and proprioceptive information is mapped directly onto the multisensory neuronal populations that represent one's own body in ego-centric coordinates. The present findings could have groundbreaking industrial and clinical applications. Experiencing swapping bodies with other individuals could provide a valuable tool for research on body image disorders or self-identity in social psychology. Likewise, experiencing ‘becoming’ a humanoid robot in tele-robotics and feeling ownership of simulated bodies in virtual reality applications would probably enhance user control, realism, and the feeling of ‘presence’ [21], [22], [23], [50]. With respect to the tele-operator literature, it is interesting to note that there are many anecdotal reports of people feeling a robotic arm to be like their own when the robot arm is viewed from a first person perspective via cameras mounted on the robot and when the movements of the robot's arms reproduce the person's movements in real time [51]. The present paper provides the experimental data and a cognitive-neuroscience-informed model for explaining how illusory ownership of limbs and entire bodies might be evoked in tele-operator systems (see also Slater et al. [50]). In conclusion, these experiments have demonstrated how remarkably easy it is to ‘move’ a human centre of awareness from one body to another. This speaks directly to the classical question of the relationship between human consciousness and the body, which has been discussed by philosophers, psychologists, and theologians for centuries [1], [3], [4], [11]. The continuous integration of multisensory and motor signals in ego-centric reference frames thus maintains the co-alignment between the experienced self and the physical body. Methods:
For each of the five experiments, we recruited separate groups of naïve healthy volunteers. In the first experiment, we tested thirty-two young adults (sixteen females, mean age 25±6 years). The second experiment involved ten individuals (two females, mean age 25±4 years), the third one consisted of a group of thirteen participants (eight females, mean age 27±6.5 years), and the fourth one was another group of twelve volunteers (four females, mean age 29±6 years). For the fifth experiment, twenty participants (13 females, mean age = 27±6.5 years) were recruited. All participants gave their written informed consent prior to participating in the relevant experiment. The studies were approved by the local Ethical Committee of Karolinska Institute.
In all experiments, participants wore a set of head-mounted displays, HMD, (Cybermind Visette Pro PAL, Cybermind Interactive, Maastricht, the Netherlands; Display Resolution = 640×480; true stereoscopic vision) with a wide field-of-view (diagonal field of view = 71.5°). These were connected to two synchronized colour CCTV cameras (Protos IV, Vista, Wokingham, Berkshire, UK) attached side-by-side to special helmets. The spacing between the cameras was adjusted for each participant to ensure that it matched the distance between their eyes (8–10 cm). The CCTV signals were relayed directly to the HMDs, without any software conversion, and thus were presented without noticeable delay. In experiments one, two, three, and four, the participants could clearly recognise the mannequin as a mannequin and in experiment five, they could see their own body and that of the other person.
The skin conductance responses were recorded with a Biopac System MP150 (Goleta, USA). Two electrodes were attached to the index and middle fingers of the participants' left hands using Signa electrode gel (Parker Laboratories, INC., New Jersey, USA). The data were registered with a Biopac System MP150 (100 samples per second) and processed with the Biopac software Acqknowledge for Windows ACK100W. The participant wore the electrodes for a few minutes before starting the recording. The parameters of the recording were as follows: The gain switch was set to 5 µmho/V and the CAL2 Scale Value was set to 5. The timing of the threat events was indicated in the raw data files during the recordings by the experimenter pressing a key.
In experiments 2 to 5 we used the following experimental designs: Experiment #2 consisted of three sessions, each of which consisted of four one minute long periods of synchronous or asynchronous stroking (each stroke was approximately 3 cm long; about 60 strokes were applied per minute). At the end of each period, the mannequin was threatened either with a knife or with a spoon. The order of the stimulation conditions and the type of object used as threat were randomized across sessions and participants [e.g. (Sk As Ak Ss) (As Ss Sk Ak) (As Sk Ak Ss), where S and A stand for synchronous or asynchronous stimulation and k and s stand for knife or spoon threat, respectively]. The data obtained from threatening the body with the spoon in the asynchronous condition was used as a low level control and is not displayed in the figures. In Experiment # 3 we used a similar protocol. It again consisted of three sessions, each of which consisted of four one minute long periods of synchronous or asynchronous stroking of the hands or of the abdomen. At the end of each period, the abdomen of the mannequin was threatened with a knife; the type of stimulation and its location (i.e. hands vs. abdomen) were randomized across sessions and participants [e.g. (Sh Aa Ah Sa) (Aa Sa Sh Ah) (Aa Sh Ah Sa), where S and A stand for synchronous or asynchronous stimulation and h and a represent the place where the stimulation was applied, i.e., to the hands or the abdomen, respectively]. Experiment # 4 was conducted according to similar protocol to that used in the second and third experiments (three, four minute long sessions, with four conditions). The conditions were synchronous or asynchronous visual and tactile stimulation of the mannequin's body or of an object that did not look like a human body. This object was a dark green rectangular box of the same height and width as the mannequin's body. The touches on the object were applied at the same height as on the mannequin's body (thus at the same distance from the cameras) and the knife was moved along its short side in the same way it was moved along the mannequin's abdomen. During the short breaks between the sessions when the mannequin was replaced by the object, the goggles were switched off to prevent the participants seeing what change was taking place. Experiment # 5, where the experimenter and the participants squeezed each other's hands, consisted of four sessions lasting two minutes apiece. During the whole experiment we played a metronome out loud at 40 beats per minute to assist in providing a steady and regular rhythm of the squeezing of the hand motion. In each session we threatened the real arm or the “owned” new arm twice. Two sessions corresponded to the illusion condition, with synchronous hand squeezing being conducted, and two sessions to the asynchronous condition. The two sessions used in the experiment were repeated twice in a pseudo-randomized order [(1, 2, 2, 1) or (2, 1, 1, 2)] to minimize the effect of presentation order. Within each session we randomized the order of which hand was threatened (either the experimenter's hand or the participant's hand). Further, the order of sessions and presentations were balanced across individuals. Within each session we threatened the hands once every 25 to 35 seconds, with the exact timing being varied to avoid anticipatory effects.
Each time that the knife or spoon was slid along the mannequin's abdomen (experiments 2, 3 and 4) or the knife moved above the wrists (experiment 5) took approximately 3 seconds. The motion was performed so that the knife and the spoon were always moved along the horizontal axis from left to right in the field of view of the HMDs. During the movement the object was inserted slightly into the mannequin's abdomen in a small gap between the upper and lower parts of the mannequin's body. To make this possible we placed two circular sticky patches (0.5 cm high, 1 cm diameter) between the torso and the lower part of the body of the mannequin, thereby, creating a cleft in the lower part of the abdomen of the mannequin that was not visible from the perspective of the cameras (Figure 9a). The objects used to provide the threat were moved along the abdomen in such a way that it looked as if the object was ‘cutting’ into the dummy's body from the perspective of the cameras (Figure 9b/c). In the fourth experiment the knife was run in full contact with the rectangular object, but we could not induce the visual effect of cutting into it because of its flat surface. For this particular experiment we adjusted the way that the knife threat was applied to the mannequin so that the knife was moved along touching the dummy's body, but without appearing to cut into it. Great care was taken to move the knife or the spoon in exactly the same way from trial to trial. The SCR was identified as the peak in the conductance that occurs up to 5 seconds after the onset of the threat stimuli. The amplitude of the increase in conductance was measured as the difference between the maximal and minimal value of the response identified in this time-window. We calculated the average of the all responses including the trials where no response was apparent, thus, analysing the magnitude of the SRC [52]. Participants who did not show a reliable threat-evoked SCR (‘null responders’), i.e. had zero responses in more than two-thirds of the trials, were excluded from the analysis.
The data obtained from the five different experiments were tested using the Kolmogorov-Smirnov test to determine whether they fitted the requirements for a normal distribution. Only the data from the first and the fourth experiments passed the normality test, therefore we used parametric statistical tests to process the data obtained in those two experiments and the data from the other three experiments were tested with non-parametric statistical tests. In all statistical tests, we set alpha to 5%.
Author Contributions

References

1. James W, editor. (1890) Prinicples of Psychology:. H Holt and Company.
2. Jeannerod M (2003) The mechanism of self-recognition in humans. Behavioural Brain Research 142: 1–15. Find this article online
3. Merleau-Ponty M, editor. (1945) Phénoménologie de la perception. Paris: Gallimard.
4. Metzinger T, editor. (2003) Being No One: The Self-Model Theory of Subjectivity:. MIT Press.
5. Botvinick M (2004) Neuroscience. Probing the neural basis of body ownership. Science 305: 875–877. Find this article online
6. Ehrsson HH (2007) The Experimental Induction of Out-of-Body Experiences. Science 317: 1048–. Find this article online
7. Ehrsson HH, Spence C, Passingham RE (2004) That's My Hand! Activity in Premotor Cortex Reflects Feeling of Ownership of a Limb. Science 305: 875–877. Find this article online
8. Lenggenhager B, Tadi T, Metzinger T, Blanke O (2007) Video Ergo Sum: Manipulating Bodily Self-Consciousness. Science 317: 1096–1099. Find this article online
9. Graziano M, Botvinick M (2002) How the brain represents the body: insights from neurophysiology and psychology. In: Prinz W, Hommel B, editors. Common Mechanisms in Perception and Action: Attention and Performance XIX. Oxford: Oxford University Press.
10. Makin TR, Holmes NP, Ehrsson HH (2008) On the other hand: Dummy hands and peripersonal space. Behavioural Brain Research 191: 1–10. Find this article online
11. Churchland PS (2002) Self-Representation in Nervous Systems. Science 296: 308–310. Find this article online
12. Baier B, Karnath H-O (2008) Tight Link Between Our Sense of Limb Ownership and Self-Awareness of Actions. Stroke 39: 486–488. Find this article online
13. Critchley M (1953) The Parietal Lobes. London: Edward Arnold.
14. Meador KJ, Loring DW, Feinberg TE, Lee GP, Nichols ME (2000) Anosognosia and asomatognosia during intracarotid amobarbital inactivation. Neurology 55: 816–820. Find this article online
15. Blanke O, Landis T, Spinelli L, Seeck M (2004) Out-of-body experience and autoscopy of neurological origin. Brain 127: 243–258. Find this article online
16. Blanke O, Ortigue S, Landis T, Seeck M (2002) Neuropsychology: Stimulating illusory own-body perceptions. Nature 419: 269–270. Find this article online
17. Botvinick M, Cohen J (1998) Rubber hands ‘feel’ touch that eyes see. Nature 391: 756–756. Find this article online
18. Costantini M, Haggard P (2007) The rubber hand illusion: Sensitivity and reference frame for body ownership. Consciousness and Cognition 16: 229–240. Find this article online
19. Tsakiris M, Haggard P (2005) The Rubber Hand Illusion Revisited: Visuotactile Integration and Self-Attribution. Journal of Experimental Psychology: Human Perception and Performance 31: 80–91. Find this article online
20. Gibson JJ, editor. (1979) The ecological approach to visual perception. Hillsdale, New Jersey Lawrence Erlbaum Associates, Publishers.
21. Minsky M (1980) Telepresence. Omni 45: Find this article online
22. Sanchez-Vives MV, Slater M (2005) From presence to consciousness through virtual reality. Nat Rev Neurosci 6: 332–339. Find this article online
23. Slater M, Frisoli A, Tecchia F, Guger C, Lotto B, et al. (2007) Understanding and realizing presence in the Presenccia project. IEEE Comput Graph Appl 27: 90–93. Find this article online
24. Armel KC, Ramachandran VS (2003) Projecting sensations to external objects: evidence from skin conductance response. Proceedings of the Royal Society B: Biological Sciences 270: 1499–1506. Find this article online
25. Ehrsson HH, Wiech K, Weiskopf N, Dolan RJ, Passingham RE (2007) Threatening a rubber hand that you feel is yours elicits a cortical anxiety response. Proceedings of the National Academy of Sciences 104: 9828–9833. Find this article online
26. Craig AD (2002) How do you feel? Interoception: the sense of the physiological condition of the body. Nat Rev Neurosci 3: 655–666. Find this article online
27. Craig AD (2003) Interoception: the sense of the physiological condition of the body. Current Opinion in Neurobiology 13: 500–505. Find this article online
28. Lenggenhager B, Smith S, Blanke O (2006) Functional and neural mechanisms of embodiment: importance of the vestibular system and the temporal parietal junction. Rev Neurosci 17: 643–657. Find this article online
29. Graziano M, Cooke D (2006) Parieto-frontal interactions, personal space, and defensive behavior. Neuropsychologia 44: 845–859. Find this article online
30. Rizzolatti G, Scandolara C, Matelli M, Gentilucci M (1981) Afferent properties of periarcuate neurons in macaque monkeys. I. Somatosensory responses. Behavioural Brain Research 2: 125–146. Find this article online
31. Castiello U (2005) The neuroscience of grasping. Nat Rev Neurosci 6: 726–736. Find this article online
32. Graziano MSA (1999) Where is my arm? The relative role of vision and proprioception in the neuronal representation of limb position. Proceedings of the National Academy of Sciences of the United States of America 96: 10418–10421. Find this article online
33. Jeannerod M (1984) The timing of natural prehension movements. Journal of motor behaviour 16: 235–254. Find this article online
34. Jeannerod M, Arbib MA, Rizzolatti G, Sakata H (1995) Grasping objects: the cortical mechanisms of visuomotor transformation. Trends in Neurosciences 18: 314–320. Find this article online
35. Welch RB, Warren DH (1986) Intersensory interactions. In: Kaufman L, Thomas JP, editors. Handbook of Perception and Human Performance. New York: K.R. Boff. pp. 25.21–25.36.
36. Lackner J (1988) Some proprioceptive influences on the perceptual representation of body shape and orientation. Brain 111: 281–297. Find this article online
37. Levelt WJM, editor. (1965) On binocular rivalry. The Hague: Van Gorcum.
38. Naito E, Roland PE, Ehrsson HH (2002) I Feel My Hand Moving: A New Role of the Primary Motor Cortex in Somatic Perception of Limb Movement. Neuron 36: 979–988. Find this article online
39. Andersen RA, Snyder LH, Bradley DC, Xing J (1997) Multimodal representation of space in the posterior parietal cortex and its use in planning movements. Annual Review of Neuroscience 20: 303–330. Find this article online
40. Duhamel J-R, Bremmer F, BenHamed S, Graf W (1997) Spatial invariance of visual receptive fields in parietal cortex neurons. Nature 389: 845–848. Find this article online
41. Fogassi L, Gallese V, Fadiga L, Luppino G, Matelli M, et al. (1996) Coding of peripersonal space in inferior premotor cortex (area F4). J Neurophysiol 76: 141–157. Find this article online
42. Graziano MSA, Cooke DF, Taylor CSR (2000) Coding the Location of the Arm by Sight. Science 290: 1782–1786. Find this article online
43. Graziano MSA, Hu XT, Gross CG (1997) Visuospatial Properties of Ventral Premotor Cortex. J Neurophysiol 77: 2268–2292. Find this article online
44. Deneve S, Pouget A (2004) Bayesian multisensory integration and cross-modal spatial links. J Physiol Paris 98: 249–258. Find this article online
45. Koerding KP, Beierholm U, Ma WJ, Quartz S, Tenenbaum JB, et al. (2007) Causal Inference in Multisensory Perception. Plos One. Find this article online
46. Wolpert DM (2007) Probabilistic models in human sensorimotor control. Human Movement Science 26: 511–524. Find this article online
47. Avillac M, Ben Hamed S, Duhamel J-R (2007) Multisensory Integration in the Ventral Intraparietal Area of the Macaque Monkey. J Neurosci 27: 1922–1932. Find this article online
48. Altschuler EL, Ramachandran VS (2007) A simple method to stand outside oneself. Perception 36: 632–634. Find this article online
49. Stratton GM (1899) The spatial harmony of touch and sight. Mind 8: 492–505. Find this article online
50. Slater M, Perez-Marcos D, Ehrsson HH, Sanchez-Vives MV (2008) Towards a digital body: The virtual arm illusion. Frontiers in Human Neuroscience. Find this article online
51. Cole J, Sacks O, Waterman I (2000) On the immunity principle: a view from a robot. Trends in Cognitive Sciences 4: 167–167. Find this article online
52. Dawson M, Schell A, Filion D (2007) The electrodermal system. In: Cacioppo J, Tassinary L, Berntson G, editors. The handbook of psychophysiology. Cambridge: Cambridge University Press. pp. 152–191.

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Una aplicación permite utilizar la misma identidad virtual en chats, SMS y televisión

La aplicación, que se ha presentado en el último número de la revista Mobile Networks & Applications , es una arquitectura informática que permite crear personajes virtuales, denominados 'avatares', compatibles con los chat, los teléfonos móviles y la televisión de tal modo que a todos estos medios se accede desde la identidad no real .
http://www.laflecha.net/canales/blackhats/una-aplicacion-permite-utilizar-la-misma-identidad-virtual-en-chats-sms-y-television?_xm=newsletter
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La sociología de los mundos virtuales en Internet
En el mundo real, rastrear toda la red social de una persona, que podría incluir cientos de contactos que sirven para diferentes propósitos, es casi imposible. Pero en juegos virtuales online como EverQuest II, donde decenas de miles de personas dejan huellas digitales a medida que chatean con otros, realizan misiones juntas, forman grupos y compran y venden bienes, los sociólogos han descubierto una mina de oro de datos sobre redes sociales.

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http://www.openinterface.org/home/

OPENINTERFACE





Presenccia

http://presenccia.org/
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http://jvwresearch.org/index.php?_cms=default,0,0

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