Representation Of Body Research Articles

Temporal visuomotor synchrony induces embodiment towards an avatar with biomechanically impossible arm movements

Visuomotor synchrony in time and space induces a sense of embodiment towards virtual bodies experienced in first-person view using Virtual Reality (VR). Here, we investigated whether temporal visuomotor synchrony affects avatar embodiment even when the movements of the virtual arms are spatially altered from those of the user in a non-human-like manner. In a within-subjects design VR experiment, participants performed a reaching task controlling an avatar whose lower arms bent in inversed and biomechanically impossible directions from the elbow joints. They performed the reaching task using this “unnatural avatar” as well as a “natural avatar,” whose arm movements and positions spatially matched the user. The reaching tasks were performed with and without a one second delay between the real and virtual movements. While the senses of body ownership and agency towards the unnatural avatar were significantly lower compared to those towards the natural avatar, temporal visuomotor synchrony did significantly increase the sense of embodiment towards the unnatural avatar as well as the natural avatar. These results suggest that temporal visuomotor synchrony is crucial for inducing embodiment even when the spatial match between the real and virtual limbs is disrupted with movements outside the pre-existing cognitive representations of the human body.

Review

Art can be particularly an effective means of building transnational understanding across cultural divides. Specifically, the act of making art to express conflict, sexuality and identity is significant as Arab women have frequently been marginalised and excluded from such a site of visibility and meaning. Contemporary Arab women artists not only contribute to global feminist theory but also deal with their aesthetic, visual and personal concerns. The Body in Twilight: Representation of the Human Body, Sexuality and Struggle in Contemporary Arab Art is a book by the Syrian professor of visual art and design Fassih Keiso. In this book, Keiso explores the representation of the human body in contemporary Arab art and its relationship to issues of sexuality and struggle. He argues that the representation of the body in Arab art reflects broader societal changes and struggles and that the use of the body as a site of resistance and political commentary is a common theme in contemporary Arab art. Despite the lack of images of artworks by the artists discussed in this book, the book provides a compelling contribution to comparative gender and feminist art and the broader international art on the centrality of sexuality in politics and society.

Dripping in molasses: Black feminist nostalgia and Kara Walker’s A Subtlety

ABSTRACT Kara Walker is best known for her depictions of sexualized violence and gendered racism during slavery in the form of black paper silhouettes. Scholars such as Salamishah Tillet argue that Walker's art, along with art by some of her post-civil rights contemporaries, offers ‘aesthetic interventions’ to problematic racial histories as part of a larger project of memory reclamation and justice. Walker's A Subtlety, Or the Marvelous Sugar Baby, an Homage to the unpaid and overworked Artisans who have refined our Sweet tastes from the cane fields to the Kitchens of the New World on the Occasion of the demolition of the Domino Sugar Refining Plant is another such interventionist project. Debuting in the Williamsburg neighbourhood of Brooklyn, New York in May of 2014, A Subtlety explores how a figure like mammy ‘survives as a cultural force that influences and reflects a national conscience’ (Wallace Sanders [2008]. Mammy: a century of race, gender, and southern memory. Ann Arbor, MI: University of Michigan Press, 12). And yet, to say that the historical rootedness of the title, sugar sphinx sculpture, and molasses-covered walls and cherub-faced small figures throughout the installation were ambiguous to some spectators, is an understatement. Hundreds of photographs and videos were uploaded to social media sites with people making gestures towards the figure that some critics deemed highly inappropriate. This paper explores how A Subtlety both understands and undermines representations of Black women's bodies and how Black artists in the African diaspora contend with complex cultural signs of the past in the present. Utilizing studies of Black feminist theory and visual culture, I argue that Walker’s A Subtlety – and her art more broadly – offers theoretical and geographic space to ponder where Black pleasure and collective memory can exist in systems of misogynoir, as well as in the Black nostalgic imagination.

Experimental protocol to investigate cortical, muscular and body representation alterations in adolescents with idiopathic scoliosis.

Adolescent idiopathic scoliosis (AIS) is the most common form of scoliosis. AIS is a three-dimensional morphological spinal deformity that affects approximately 1-3% of adolescents. Not all factors related to the etiology of AIS have yet been identified. The primary aim of this experimental protocol is to quantitatively investigate alterations in body representation in AIS, and to quantitatively and objectively track the changes in body sensorimotor representation due to treatment. Adolescent girls with a confirmed diagnosis of mild (Cobb angle: 10°-20°) or moderate (21°-35°) scoliosis as well as age and sex-matched controls will be recruited. Participants will be asked to perform a 6-min upright standing and two tasks-named target reaching and forearm bisection task. Eventually, subjects will fill in a self-report questionnaire and a computer-based test to assess body image. This evaluation will be repeated after 6 and 12 months of treatment (i.e., partial or full-time brace and physiotherapy corrective postural exercises). We expect that theta brain rhythm in the central brain areas, alpha brain rhythm lateralization and body representation will change over time depending on treatment and scoliosis progression as a compensatory strategy to overcome a sensorimotor dysfunction. We also expect asymmetric activation of the trunk muscle during reaching tasks and decreased postural stability in AIS. Quantitatively assess the body representation at different time points during AIS treatment may provide new insights on the pathophysiology and etiology of scoliosis.

Short-term effects of a multidisciplinary inpatient intensive rehabilitation treatment on body image in anorexia nervosa

BackgroundPositive changes in weight gain and eating pathology were reported after inpatient treatments for anorexia nervosa (AN). However, changes in the physical body do not always mirror changes in the imagined body. Here, the effect of a treatment focused on body image (BI) was described.MethodsThis retrospective observational study had a quasi-experimental pre-post design without the control group. During the treatment, participants (N = 72) undertake a variety of activities focused on BI. The main outcome was tested through the Body Uneasiness Test.ResultsAt the end of the treatment, BI uneasiness decreased with a significant increase in weight gain.ConclusionThis study highlights the positive short-term effect of a multidisciplinary inpatient intensive rehabilitation treatment on BI in AN. We encourage to design of psychological treatments focusing on the cognitive and emotional bodily representation (i.e. the body in the mind) to increase physical well-being.

An Overview of the Body Schema and Body Image: Theoretical Models, Methodological Settings and Pitfalls for Rehabilitation of Persons with Neurological Disorders.

Given the widespread debate on the definition of the terms "Body Schema" and "Body Image", this article presents a broad overview of the studies that have investigated the nature of these types of body representations, especially focusing on the innovative information about these two representations that could be useful for the rehabilitation of patients with different neurological disorders with motor deficits (especially those affecting the upper limbs). In particular, we analyzed (i) the different definitions and explicative models proposed, (ii) the empirical settings used to test them and (iii) the clinical and rehabilitative implications derived from the application of interventions on specific case reports. The growing number of neurological diseases with motor impairment in the general population has required the development of new rehabilitation techniques and a new phenomenological paradigm placing body schema as fundamental and intrinsic parts for action in space. In this narrative review, the focus was placed on evidence from the application of innovative rehabilitation techniques and case reports involving the upper limbs, as body parts particularly involved in finalistic voluntary actions in everyday life, discussing body representations and their functional role.

Errors and inaccuracies about celestial bodies in the Greek texts of children’s fiction books about atmospheric pollution

This paper examines children’s fiction books on air pollution in terms of the accuracy of their content in the representation of celestial bodies. The qualitative content analysis identifies and records in the text of 18 books passages containing errors and inaccuracies about celestial bodies. The passages are organized and presented in a category system while also being linked to the possible alternative ideas they may generate in children. The results show that the Earth, the planets, the Sun, and the stars are only sometimes represented based on scientific standards. Finally, the common errors and inaccuracies are presented. At the same time, suggestions are made for using these books in teaching and learning in science and environmental education in order to avoid misconceptions from their students.

Embodied perspective-taking enhances interpersonal synchronization: A body-swap study

Humans exhibit a strong tendency to synchronize movements with each other, with visual perspective potentially influencing interpersonal synchronization. By manipulating the visual scenes of participants engaged in a joint finger-tapping task, we examined the effects of 1st person and 2nd person visual perspectives on their coordination dynamics. We hypothesized that perceiving the partner's movements from their 1st person perspective would enhance spontaneous interpersonal synchronization, potentially mediated by the embodiment of the partner's hand. We observed significant differences in attractor dynamics across visual perspectives. Specifically, participants in 1st person coupling were unable to maintain de-coupled trajectories as effectively as in 2nd person coupling. Our findings suggest that visual perspective influences coordination dynamics in dyadic interactions, engaging error-correction mechanisms in individual brains as they integrate the partner's hand into their body representation. Our results have the potential to inform the development of applications for motor training and rehabilitation.

The left–right reversed visual feedback of the hand affects multisensory interaction within peripersonal space

The interaction between vision and touch, known as the crossmodal congruency effect, has been extensively investigated in several research studies. Recent studies have revealed that the crossmodal congruency effect involves body representations. However, it is unclear how bodily information (e.g., location, posture, motion) is linked to visual and tactile inputs. Three experiments were conducted to investigate this issue. In Experiment 1, participants performed a crossmodal congruency task in which both their hand appearance and the motor trajectories were left–right reversed. The results showed that the crossmodal congruency effect was not observed in the reversal condition, whereas participants showed significant crossmodal congruency in the control condition, in which there was no visual manipulation of the hand. In Experiments 2 and 3, where either the hand appearance or motor trajectory was left–right reversed individually, a significant crossmodal congruency effect was observed. This study demonstrated that visual manipulation of hand appearance and motor trajectories both affected the crossmodal congruency effect, although neither showed a dominant effect that solely altered the crossmodal congruency effect. The present results provide insights into the relationship between visual-tactile interactions and bodily information.

Disturbed body schema, perceptual body image, and attitudinal body image in patients with borderline personality disorder.

Borderline personality disorder (BPD) is a severe mental disorder that affects attitudes toward the body. However, whether this condition also affects body schema and perceptual body image remains unclear. Previous questionnaire-based studies found dissatisfaction with one's body in patients with BPD. In addition to attitudinal body image, our study investigates whether body schema and perceptual body image are disturbed in patients with BPD. Our study included 31 patients diagnosed with BPD (25 women) and 30 healthy individuals (19 women) (Mage = 29 for both groups). The SCID-5-PD interview was used to determine personality disorder. Attitudinal body image was measured using the Body Attitude Test (BAT) factors. Body schema and perceptual body image were measured by two conditions of a body representation task, the body portraying method (BPM). BPD patients achieved higher scores in all three BAT factors and were more susceptible to misinformation in both conditions of BPM. Based on the results, BPD patients appear to have more negative attitudes toward their bodies and worse perceptual body image and body schema. The novel finding of our study is that, besides the previously found attitudinal dissatisfaction with the body, individuals with BPD also show disturbances at the levels of body schema and perceptual body image. Our findings concerning disturbances in body schema and perceptual body need further research into their etiological factors and provide new therapeutic targets for the treatment of BPD.

Masculine nations, queer bodies and the in/visibilities of gender

ABSTRACT This article explores the overlapping systems of gender and nation and particularly the connections of masculinities with national construction. Based on the analysis of the video ‘Por España’ performed by the queer artist Samantha Hudson, I discuss how in/visibilities affect the recognizability of queer bodies in relation to national construction and unveil how hegemonic masculinities have been the norm. Queer ‘inappropriate’ bodies have been left aside from the hegemonic representations of the national bodies in the military, in politics or in sport. Queer visible bodies attached to national symbols oppose the still prevalent masculinist models of patriotism in a context of growing right-wing masculinities and antigender right-wing populisms. Changing the rules of what bodies can appear in public in relation to national symbols can affect the construction of the collective ‘we’ and turn invisibility into recognition and political agency. In/visibilities are ambivalent and paradoxical: they trigger empowerment and agency but also stigma, repression and control. Sticking queer bodies to national sentiments (‘Por España’) and symbols (bulls, Spanish flags, folklore, food, dress and so on) is an invitation to see other bodies, genders and sexualities and to imagine other nations that question the traditional geometries of power and their visibility regimes.

The Pleasures and Power in a Trans Identity: A “Found Poem” Found in a Discussion About Fashion

This poem represents the qualitative findings from a study on transgender individual’s relationship to fashion. Eight transgender young adults were interviewed about their gender identity and presentation, as well as their use of clothing and fashion style to represent themselves. Within these interviews, all participants shared the pleasures and power they derive from their transgender identities. Using direct quotes, and intentionally arranging phrases and stories found within the interview transcripts, the authors created this found poem. A research poem was chosen to best represent this data as it allows the participants to maintain their power using their voices directly to more authentically represent their pleasures and joys in their identities. Themes that emerged, and are represented by the six color groups of stanzas, which include making connections to others and the queer community (red); gaining a unique perspective of the world (orange); finding opportunities and enjoying fluidity (yellow); enhancing pleasure in the body and physical representation of gender (green); creating power in visibility and representation (blue); and embracing the delight and freedom in a trans identity (purple).

Luce Irigarays Body Theory and Film Rouge: Female Image of Courtesan Ruhua

The representation of charming female bodies is a distinct characteristic of feminine movies directed by Guan Jinpeng. Rouge, one of his representative works, illustrates the hope and despair of a courtesan named Ruhua. Although several studies revealed the political metaphor of her body image, few researchers put emphasis on the female sentiment behind it. Therefore, by means of textual analysis, this study explores the life experience of Ruhua mirrored by her body image based on three theoretical perspectives proposed by Luce Irigaray in The Sex Which is Not One, including market value, sexual pleasure and class oppression of the female body. The research finding is that in Rouge, lens languages such as compositions, lights and clothes are conceived elaborately to depict Ruhuas body feelings, which not only implies her disadvantaged position in terms of wealth, sex and power but also reflects her individual consciousness against her dominated body as she is craving for maintaining a relatively equal relationship with her lover. The body narrative in Rouge subverts traditional films made by other male directors that commodify the female body under the male gaze and sets an example for the future feminine movie of how the depiction of the female body destroys gender power.

The (cognitive) future of motor control and learning.

An ongoing debate exists regarding the compatibility of dynamic systems theory (DST) and symbol processing accounts (SPA), where SPA assume abstract representations and processing. Another aspect under discussion is if either one appropriately describes and explains motor control and the modification of motor skills. Both frameworks have their strengths and weaknesses. DST provides mechanistic explanations and takes system complexity and the environment into account without reference to mental entities. System behaviour is described mathematically and considered deterministic. In contrast, SPA propose that abstract content, that is, mental representations of the (own) body, and task requirements are critically important for movement control. It is argued that neither approach nor an (unaccomplished) unification of these frameworks can achieve a comprehensive understanding of motor control and learning. In this perspective article, it is argued that further effective sources of motor learning, such as emotional support and motivational guidance, have the potential to improve and preserve motor skills indirectly and should, thus, be recognised. Qualitative approaches focussing on understanding the athlete and the situation might be appropriate for applied work.

Hypnotic suggestion versus sensory modulation of bodily awareness.

Bodily awareness arises from somatosensory, vestibular, and visual inputs but cannot be reduced to these incoming sensory signals. Cognitive factors are known to also impact bodily awareness, though their specific influence is poorly understood. Here we systematically compared the effects of sensory (bottom-up) and cognitive (top-down) manipulations on the estimated size of body parts. Toward this end, in a repeated-measures design, we sought to induce the illusion that the right index finger was elongating by vibrating the biceps tendon of the left arm whilst participants grasped the tip of their right index finger (Lackner illusion; bottom-up) and separately by hypnotic suggestion (top-down), with a sham version of the Lackner illusion as an active control condition. The effects of these manipulations were assessed with perceptual and motor tasks to capture different components of the representation of body size. We found that hypnotic suggestion significantly induced the illusion in both tasks relative to the sham condition. The magnitudes of these effects were stronger than those in the Lackner illusion condition, which only produced a significantly stronger illusion than the sham condition in the perceptual task. We further observed that illusion magnitude significantly correlated across tasks and conditions, suggesting partly shared mechanisms. These results are in line with theories of separate but interacting representational processes for perception and action and highlight the influence of cognitive factors on low-level body representations.

Spatial perspective and identity in visual awareness of the bodily self-other distinction

Spatial perspective and identity of visual bodily stimuli are two key cues for the self-other distinction. However, how they emerge into visual awareness is largely unknown. Here, self- or other-hands presented in first- or third-person perspective were compared in a breaking-Continuous Flash Suppression paradigm (Experiment 1) measuring the time the stimuli need to access visual awareness, and in a Binocular Rivalry paradigm (Experiment 2), measuring predominance in perceptual awareness. Results showed that, irrespectively of identity, first-person perspective speeded up the access, whereas the third-person one increased the dominance. We suggest that the effect of first-person perspective represents an unconscious prioritization of an egocentric body coding important for visuomotor control. On the other hand, the effect of third-person perspective indicates a conscious advantage of an allocentric body representation fundamental for detecting the presence of another intentional agent. Summarizing, the emergence of self-other distinction into visual awareness would strongly depend on the interplay between spatial perspectives, with an inverse prioritization before and after conscious perception. On the other hand, identity features might rely on post-perceptual processes.

Joint Moment Responses to Different Modes of Augmented Visual Feedback of Joint Kinematics during Two-Legged Squat Training

This study examined the effects of different modes of augmented visual feedback of joint kinematics on the emerging joint moment patterns during the two-legged squat maneuver. Training with augmented visual feedback supports improved kinematic performance of maneuvers related to sports or daily activities. Despite being representative of intrinsic motor actions, joint moments are not traditionally evaluated with kinematic feedback training. Furthermore, stabilizing joint moment patterns with physical training is beneficial to rehabilitating joint-level function (e.g., targeted strengthening and conditioning of muscles articulating that joint). Participants were presented with different modes of augmented visual feedback to track a target squat-motion trajectory. The feedback modes varied along features of complexity (i.e., number of segment trajectories shown) and body representation (i.e., trajectories shown as sinusoids versus dynamic stick-figure avatars). Our results indicated that mean values and variability (trial-to-trial standard deviations) of joint moments are significantly (p < 0.05) altered depending on the visual feedback features being applied, the specific joint (ankle, knee, hip), and the squat movement phase (early, middle, or late time window). This study should incentivize more optimal delivery of visual guidance during rehabilitative training with computerized interfaces (e.g., virtual reality).

Cortical signatures of visual body representation develop in human infancy

Human infants cannot report their experiences, limiting what we can learn about their bodily awareness. However, visual cortical responses to the body, linked to visual awareness and selective attention in adults, can be easily measured in infants and provide a promising marker of bodily awareness in early life. We presented 4- and 8-month-old infants with a flickering (7.5 Hz) video of a hand being stroked and recorded steady-state visual evoked potentials (SSVEPs). In half of the trials, the infants also received tactile stroking synchronously with visual stroking. The 8-month-old, but not the 4-month-old infants, showed a significant enhancement of SSVEP responses when they received tactile stimulation concurrent with the visually observed stroking. Follow-up experiments showed that this enhancement did not occur when the visual hand was presented in an incompatible posture with the infant’s own body or when the visual stimulus was a body-irrelevant video. Our findings provide a novel insight into the development of bodily self-awareness in the first year of life.

The missing: Exploring the use of photographs in “working through” the natal body with transgender youth

ABSTRACT This paper focuses on how for some young people who identify as transgender, the anticipation, and/or the actual process, of transitioning represents a movement away from something in themselves that feels wrong, painful, or traumatic and that has not yet been consciously recognised as such. This becomes a ‘missing’ part of the self’s experience, locked into the body. I suggest that the process of identifying and restitution of ‘the missing’ part requires working through the natal body in its metaphorical and literal senses, in the service of expanding autonomous choice about how to find a hospitable home in the body. Building on Money-Kyrle’s three ‘facts of life’, I propose a fourth one, namely the inescapable fact of our embodied nature, to underscore that our personal history always includes our embodied history, hence the importance of working through what the natal body unconsciously represents. I describe the use of photographs during psychoanalytic psychotherapy with young people who have commenced social transitioning, to work through visual representations of the natal body in the service of facilitating the working through, in its psychoanalytic sense, of the natal body’s unconscious narrative. I suggest that deploying this visual mode may be especially helpful in engaging young people on the autistic spectrum who nowadays comprise a significant minority of transgender young people.

Numerical investigation of a new hybrid floating wind turbine concept

In today’s energy scenario dominated by the need to develop new methods of generating electricity, energy-intensive infrastructures are a promising solution towards energy self-sufficiency and environmental sustainability. Floating offshore wind turbine represents one of the major solution to exploit renewable energies. Currently, the increase of offshore wind market opens up the possibility of integrating different technologies to take advantage of marine energy potential, in particular wave energy.
 This work presents a new wave-wind hybrid floating platform with three Oscillating Water Columns (OWC) integrated in a floating offshore wind spar buoy. The design methodology is described showing the size of geometric characteristics of OWCs and the size of the energy conversion system. The hybrid system is investigated by a time-domain model that integrates the wind turbine model, the hydrodynamics of the floater, the thermodynamics of the OWC air chambers, and the damping effect induced by the OWC air turbine. The thermo-aero-hydro coupled numerical framework is described to highlight the implementation of the thermodynamic model in WEC-Sim/MATLAB environment. Specifically, the water column dynamics are solved as pistonrigid body representation, enabling the time-domain analysis of the OWC dynamic behaviour. Impulse turbines are considered as OWC Power Take-Offs (PTO). The resource scenario of Mediterranean Sea is considered as case study, in terms of both wind and wave conditions. The analysis focuses on the power extraction capabilities of the OWCs and on the impact of OWCs on the productivity of the wind turbine. Further developments on multi-objective design tools and on optimal PTO control design aiming power maximisation could be conducted for hybrid energy platforms based on this established numerical framework.