Body Schema Research Articles

Phenomenological Body Schema as Motor Habit in Skill Acquisition – Intentionality is in Action

The purpose of this concept-based paper was to showcase the importance of Merleau-Ponty’s (1945/2014) phenomenological body schema as motor habit in skill acquisition and perception of the world and contrast it with the standard information processing models that are solely based on cognition. Examples of disability cases are used, including Schneider’s brain damage and instances of apraxia, to exhibit that difficulty in executing certain motor skills is based on lack of body schema/motor habit and not on some gnostic disorder that inhibits representation as proposed in information processing. Habitual body movement is essential in understanding body schema as motor habit, which is a pre-reflective consciousness, an inter-sensorial unity. Motor skills are learned only via body movement because the body “grasps” and “conceives” movement by throwing itself into meaningful significations without calculating the distance between body parts and external objects. Motor skill execution is done tacitly via body schema that may involve essential external apparatus like a blind man’s cane or aerial silks in aerial practice. Constant engagement with concrete, functional movements and different ways to perform abstract movements (e.g., use of preparatory actions and vision), can improve body schema/motor habit, and thus mobility, skill performance, and understanding of the world. Keywords: body schema, motor habit,

De l’image corporelle au schéma corporel, du proximal au distal : l’activité musicale incarnée à travers l’apprentissage de techniques instrumentales

Un changement de paradigme récent dans la recherche musicale a permis aux chercheurs d’examiner les macro- et micro-processus dans la performance musicale et les processus cognitifs sous-jacents. En les reliant aux théories phénoménologiques de la perception et de la cognition incarnées, cet article se concentre sur l’activité corporelle liée à l’acquisition de techniques instrumentales – le processus d’apprentissage musical. L’interaction dynamique avec un instrument de musique, accompagnée par le jeu entre l'action et la passion, génère une alternance entre l’image corporelle et le schéma corporel dont le statut varie au fil des différentes phases de l'acquisition des compétences musicales instrumentales. Cette interaction permet aux individus de rediriger leur attention de leurs états corporels – le proximal – vers la qualité des sons musicaux et l’unicité de l’expérience musicale – le distal. Cet article soutient ainsi que le jeu instrumental peut être conçu comme un processus incarné : une prise de conscience par les musiciens du lien entre leur propre expérience et le monde musical généré par leur activité corporelle.

Coordination tending towards an anti-phase relationship determines greater sway reduction during entrainment with a simulated partner

The increased risk of falls in the older aged population demands the development of assistive robotic devices capable of effective balance support. For the development and increased user acceptance of such devices, which provide balance support in a human-like way, it is important to understand the simultaneous occurrence of entrainment and sway reduction in human-human interaction. However, sway reduction has not been observed yet during a human touching an external, continuously moving reference, which rather increased human body sway. Therefore, we investigated in 15 healthy young adults (27.20±3.55 years, 6 females) how different simulated sway-responsive interaction partners with different coupling modes affect sway entrainment, sway reduction and relative interpersonal coordination, as well as how these human behaviours differ depending on the individual body schema accuracy. For this, participants were lightly touching a haptic device that either played back an average pre-recorded sway trajectory (“Playback”) or moved based on the sway trajectory simulated by a single-inverted pendulum model with either a positive (Attractor) or negative (Repulsor) coupling to participant's body sway. We found that body sway reduced not only during the Repulsor-interaction, but also during the Playback-interaction. These interactions also showed a relative interpersonal coordination tending more towards an anti-phase relationship, especially the Repulsor. Moreover, the Repulsor led to the strongest sway entrainment. Finally, a better body schema contributed to a reduced body sway in both the “reliable” Repulsor and the “less reliable” Attractor mode. Consequently, a relative interpersonal coordination tending more towards an anti-phase relationship and an accurate body schema are important to facilitate sway reduction.

Can I Squeeze Through? Effects of Self-Avatars and Calibration in a Person-Plus-Virtual-Object System on Perceived Lateral Passability in VR.

With the popularity of Virtual Reality (VR) on the rise, creators from a variety of fields are building increasingly complex experiences that allow users to express themselves more naturally. Self-avatars and object interaction in virtual worlds are at the heart of these experiences. However, these give rise to several perception based challenges that have been the focus of research in recent years. One area that garners most interest is understanding the effects of self-avatars and object interaction on action capabilities or affordances in VR. Affordances have been shown to be influenced by the anthropometric and anthropomorphic properties of the self-avatar embodied. However, self-avatars cannot fully represent real world interaction and fail to provide information about the dynamic properties of surfaces in the environment. For example, pressing against a board to feel its rigidity. This lack of accurate dynamic information can be further amplified when interacting with virtual handheld objects as the weight and inertial feedback associated with them is often mismatched. To investigate this phenomenon, we looked at how the absence of dynamic surface properties affect lateral passability judgments when carrying virtual handheld objects in the presence or absence of gender matched body-scaled self-avatars. Results suggest that participants can calibrate to the missing dynamic information in the presence of self-avatars to make lateral passability judgments, but rely on their internal body schema of a compressed physical body depth in the absence of self-avatars.

Effects of Collaborative Training Using Virtual Co-embodiment on Motor Skill Learning.

Virtual reality (VR) is a promising tool for motor skill learning. Previous studies have indicated that observing and following a teacher's movements from a first-person perspective using VR facilitates motor skill learning. Conversely, it has also been pointed out that this learning method makes the learner so strongly aware of the need to follow that it weakens their sense of agency (SoA) for motor skills and prevents them from updating the body schema, thereby preventing long-term retention of motor skills. To address this problem, we propose applying "virtual co-embodiment" to motor skill learning. Virtual co-embodiment is a system in which a virtual avatar is controlled based on the weighted average of the movements of multiple entities. Because users in virtual co-embodiment overestimate their SoA, we hypothesized that learning using virtual co-embodiment with a teacher would improve motor skill retention. In this study, we focused on learning a dual task to evaluate the automation of movement, which is considered an essential element of motor skills. As a result, learning in virtual co-embodiment with the teacher improves motor skill learning efficiency compared with sharing the teacher's first-person perspective or learning alone.

Bodily-Material Culture Techniques in the Spaces of the Devotional Revolution

Abstract This essay addresses how new procedural knowledge was promoted during the devotional revolution in nineteenth-century Ireland, particularly in relation to bodily-material culture techniques. It argues that a more orthopraxic physical disposition was a significant aspect of the experience and practice of Catholicism, and suggests ways of thinking about that in relation to religious imagination and space. In this, it sees bodies as connected to artefacts through material practices. The bodily-material culture techniques under discussion include gesture, ways of interacting with objects and spaces, and in general the embedding of new forms of material knowledge and body schema. In this, this essay re-examines the relationship between religious and secular space during this period. On the one hand, at this time the intense construction and prominent siting of thousands of religious buildings including churches, denominational institutions and entire urban quarters suggest that sacred and secular spaces were highly defined and circumscribed. However, a focus on bodies and objects also suggests the idea of immanence, and a more fluid inter-relationship between sacred and profane space than might be generally considered. The contribution draws largely on regulatory and instructive literature including catechisms and popular devotional tracts, personal testimony and specific liturgical and devotional objects and spaces.

Impact of delightful somatosensory augmented reality experience on online consumer stickiness intention

PurposeDrawing on embodied cognition theory, this study examined the impact of midair, gesture-based somatosensory augmented reality (AR) experience on consumer delight and stickiness intention. The mediating effects of three psychological states for body schema (i.e. natural symbol sets, vivid memory and human touch) on the relationships between somatosensory AR and consumer delight/stickiness intention are determined. By filling gaps in the research, we hope to provide guidance on how to drive delightful somatosensory AR marketing.Design/methodology/approachTwo experiments were conducted (Study 1 and Study 2) to test the research model and hypotheses. These experiments compared the effects of the “presence” (midair, gesture-based) and “absence” (mouse-based traditional website) conditions in somatosensory AR on consumer body schema and the creation of a delightful virtual shopping experience (i.e. consumer delight and stickiness intention).FindingsThe consumer delight and stickiness intention created in the presence condition was much higher than those in the absence condition. Consumers appeared to prefer engaging in a midair gesture-based somatosensory AR experience and exploring an augmented metaverse reality to interacting with a mouse-based traditional website. We also found that giving online consumers more somatosensory activities and kinesthetic experiences effectively inspired three psychological states of body schema in online consumers.Originality/valueThe results contribute to the AR experience and somatosensory marketing literature by revealing the role of natural symbol sets, vivid memory and the sense of human touch. This research breaks through the long-developed research paradigm on consumer delight, which has been limited to traditional entities and web contexts. We also extend embodied cognition theory to the study of somatosensory AR marketing.

Right posterior hypometabolism in Pisa syndrome of Parkinson’s disease: A key to explain body schema perception deficit?

BackgroundPisa syndrome (PS) is a trunk postural abnormality in Parkinson's disease (PD). Its pathophysiology is still debated: peripheral and central mechanisms have been hypothesized. ObjectiveTo investigate the role of nigrostriatal dopaminergic deafferentation and of brain metabolism impairment in the onset PS in PD patients. MethodsWe retrospectively selected 34 PD patients who developed PS (PS+) and who had previously undergone dopamine transporter (DaT)-SPECT and/or brain F-18 fluorodeoxyglucose PET (FDG-PET). PS + patients were divided considering leaning body side in left ((l)PS+) or right ((r)PS+). DaT-SPECT specific-to-non-displaceable binding ratio (SBR) of striatal regions (BasGan V2 software) were compared between 30 PS+ and 60 PD patients without PS (PS-) as well as between 16 (l)PS+ and 14 (r)PS + patients. Voxel-based analysis (SPM12) was used to compare FDG-PET among 22 PS+, 22 PS- and 42 healthy controls (HC) and between 9 (r)PS+ and 13 (l)PS+. ResultsNo significant DaT-SPECT SBR differences were found between PS+ and PS- groups or between (r)PD+ and (l)PS + subgroups. Compared to HC, significant hypometabolism in PS+ was found in bilateral temporal-parietal regions, mainly in the right hemisphere, whereas the right Brodmann area 39 (BA39) was relatively hypometabolic both in the (r)PS+ and in the (l)PS+. BA39 and bilateral posterior cingulate cortex were significantly hypometabolic in PS + than in PS- group. ConclusionsAs a hub of the network supervising the body schema perception, the involvement of the right posterior hypometabolism supports the hypothesis PS is a result of a somatosensory perceptive deficit rather than a nigrostriatal dopaminergic unbalance.

PHENOMENOLOGICAL RESEARCH OF IMAGINATION IN SCHIZOPHRENIA SPECTRUM DISORDERS AS A CONCEPTUAL FRAMEWORK FOR UNDERSTANDING PSYCHOTHERAPEUTIC PROCESSES AND RECOVERY STRATEGIES

Although imagination abnormalities are frequent and handicapping in schizophrenia spectrum disorders (SSDs), psychopathology lacks a conceptual framework for modeling imagination disorders. Recently, in connection with the “imaginary turn” in phenomenology, translational approaches between philosophy and psychopathology have been sought. The purpose of the article is the presentation and analysis of modern foreign phenomenological studies of imagination in SSDs by a group of researchers headed by A. Rasmussen and J. Parnas, for the possible implementation of the results in domestic practice. The author first examines the features of anomalous fantasy and imagination in SSDs from the phenomenological point of view and then presents an overview of the EAFI instrument for a semistructured, phenomenological study of anomalous fantasy and imagination through interviews. Then the author analyzes the theoretical and practical implications of such research for understanding psychotherapeutic processes and recovery strategies. The studied disorders of imagination are characterized by three phenomenological dimensions: 1) perceptualization of imagery: the experience acquires certain quasi-perceptual qualities, such as spatialization, spatiotemporal constancy and explorabilty; 2) autonomization of imagery with a quasi-involuntary flow and a sense of empirical distance between the conscious image and the sense of agency; and 3) erosion of irreality: whereas the imagination is normally lived with an ever-present character of unreality, people with SSDs can experience vivid imagery without a clear separation with the real world. Rasmussen et al. not only describe clinical experience, they also offer a conceptual model of imagination disorders as expressions of minimal self-disorders (disorders of ipseity). The researchers hypothesize that impaired ipseity itself is the core generative disorder of schizophrenia, and positive/negative symptoms derive from this core phenotype. Thus, imagination is understood as a mental domain that affects the underlying disorder, meaning that imagination has the same status as all other modes of intentional consciousness (such as perception or memory). T. Gozé and I. Fazakas go further and suggest a phenomenological distinction between fantasy and imagination, which resembles the distinction between body schema and body image.

The Influence of Emotional and Cognitive Factors on Limb Laterality Discrimination in Women with Fibromyalgia Syndrome: A Cross-Sectional Study Secondary Analysis

Previous scientific evidence has shown that patients with fibromyalgia syndrome (FMS) have alterations in the body schema. There have also been findings regarding the influence of psychological factors on pain, as well as evidence that patients with FMS have difficulty performing laterality discrimination tasks. The main objective of this study was to evaluate whether emotional and cognitive factors influence the limb laterality discrimination task in women with FMS. Seventeen of the participants were healthy female controls, and the other seventeen were women diagnosed with FMS. The main outcome measures were laterality discrimination, anxiety symptoms, depression symptoms, pain catastrophizing, and fear-related movement. The main analysis showed that patients with FMS had longer reaction times for laterality discrimination in hands (hand 20 images, p < 0.031; hands 50 images p < 0.013). In the secondary analysis, FMS patients showed emotional (anxiety (p < 0.0001); depression (p < 0.0001)) and cognitive (pain catastrophizing (p < 0.0001); fear-related movement (p < 0.0001)) disorders compared with healthy subjects. There was no correlation between limb laterality discrimination and psychological variables. In conclusion, patients with FMS showed impaired laterality discrimination, but psychological variables were not influenced. This could be due to the implicit nature of the task.

Dancing with Objects: A Psychological and Neurophysiological Analysis

Abstract This article uses the psychological concept of body schema and the neurophysiological notion of peripersonal space to discuss the phenomenon of dancing bodies that wear, handle, and share objects. The author shows the complex and dynamic relationship between body and object to be central to the experience of dancing with objects, which is investigated in terms of multisensory integration, most notably in relation to proprioceptive, haptic, and tactile perception. It is posited that, although stemming from different theoretical approaches, both the psychological and neurophysiological perspectives demonstrate how the body incorporates and is incorporated by the things it moves with.

P091 Gender focused investigation of sexual dysfunction, sexual satisfaction and body schema disorders in male and female patients with Inflammatory Bowel Disease

Abstract Background Gender-specific differences in Inflammatory Bowel Disease (IBD) have been reported for epidemiology, pathogenesis, clinical course and disease outcomes. However, when it comes to sexual health deviations regarding both biological sexes, research studies are scarce. In this context, gender could be an important modulating factor. The aim of this study was to investigate gender-specific sexual dysfunction, sexual satisfaction and body schema disorders in male and female patients with IBD. Methods A cross-sectional unicentric study was performed. 123 patients with IBD were recruited for 12 months. Of these, 50 patients were male and 73 female. Inclusion criteria included a diagnosed IBD (Crohn's disease or ulcerative colitis), age between 18 - 65 years and sufficient language skills to complete the questionnaires. Data was collected using standardised questionnaries (IBDQ, IBD-F, pMS, HBI, IIEF, BISF-W, FKKS, PHQ15, PHQ9, HADS-D). Sexual dysfunction, sexual satisfaction and body schema disorders were mainly assessed by the „Frankfurter Körperkonzeptskalen“ (FKKS), „The Brief Index of Sexual Functioning for Women“ (BISF-W) and „International Index of Erectile Function“ (IIEF). Results Significant differences (p < 0.05) were found for the pMS, FKKS, PHQ15 and PHQ9. Male patients with IBD scored higher in the FKKS, especially in the subscale „Health and physical condition scale (SGKB)“ but also on sexuality- and body-related questions, meaning that they had fewer problems with their sexuality and biological functionality. Due to the small number of only 13 male participants, the IIEF could only be assessed to a limited extent. No significant differences were found here. Female patients with IBD had higher scores in the pMS, PHQ15 and PHQ9, meaning that they suffered more from severe disease activity, somatic impairment and depression. In addition, they scored lower on the BISF-W dimension scores "Arousal" (D2) and "Pleasure/Orgasm" (D5). Conclusion Sexual health seems to be impaired in male and female patients with IBD. However, it appears that men are less affected by their IBD than women in terms of sexual well-being, mental health, aesthetics and biological functionality. The reasons behind these results are diverse and cannot be clearly determined. It could be that men are overall more resilient because of their phsyical body structure or because they tend to hide supposed weaknesses.

P073 Let′s talk about sex: an unicentric cross-sectional study on sexual dysfunction, sexual satisfaction and body schema disorders in Inflammatory Bowel Disease

Abstract Background Patients with Inflammatory Bowel Disease (IBD) suffer from a variety of physical and psychological symptoms. Especially sexual health is an often underestimated but leading concern among patients. Despite its major impact, there has been little systematic research on this topic in the past. The aim of this study was to investigate sexual dysfunction, sexual satisfaction and body schema disorders in patients with IBD compared to a healthy control group. Methods A cross-sectional unicentric study was performed. 123 patients with IBD and 71 population controls were recruited for 12 months. Inclusion criteria for the patient group included a diagnosed IBD (Crohn's Disease or Ulcerative Colitis), age between 18 - 65 years and sufficient language skills to complete the questionnaires. For the control group inclusion criteria were similar but without a diagnosed IBD. Data was collected using standardised questionnaries (IBDQ, IBD-F, pMS, HBI, IIEF, BISF-W, FKKS, PHQ15, PHQ9, HADS-D). Sexual dysfunction, sexual satisfaction and body schema disorders were mainly assessed by the „Frankfurter Körperkonzeptskalen“ (FKKS) and „The Brief Index of Sexual Functioning for Women“ (BISF-W). Results Significant differences (p < 0.05) could be found within the individual questionnaire scales. Regarding the FKKS, the control group scored higher in three of the nine scales: Health and physical condition scale (SGKB), Sexuality scale (SSEX) and Body self-acceptance scale (SSAK). A similar result was also shown in the BISF-W: population controls had higher scores in two of the seven dimension scores: "Arousal" (D2) and "Pleasure/Orgasm" (D5). Overall, when comparing the total scores of FKKS and BISF-W between patients and population controls no remarkable distinctions were identified. Conclusion Sexual health seems to be impaired in patients with IBD. Patients suffer from reduced sexual arousal, orgasmic sensation and physical well-being. In addition, they are also more inhibited in sexual contact with their partners and devalue their own body in terms of aesthetics and biological functionality. Overall, these results can help to understand the disease′s complexity considering not only clinical but also psychological factors regarding sexual well-being and point to new therapeutical directions.

Neuromotricity and body schema. Bases for the use of body percussion in the sciences of physical educa-tion and sport

The aim of this article is to propose a theoretical and practical justification on the work for the internalization of the body schema in relation to neuromotricity. For this purpose, a bibliographical review is established on the perceptual-motor variables related to the elaboration of the body schema, such as attitude, postural control, spatial structuring, temporal structuring, balance and coordination with practical exercises of body percussion for its application in the physical education sciences. In this way, applying practical resources focused on the work of cognitive and executive functions, we offer an innovative psycho-pedagogical method in the field of human motor skills. Keywords: Body schema, neuromotricity, body percussion, BAPNE, physical education, executive functions

Limb Apraxias: The Influence of Higher Order Perceptual and Semantic Deficits in Motor Recovery After Stroke.

Stroke is a leading cause of disability worldwide. Limb apraxia is a group of higher order motor disorders associated with greater disability and dependence after stroke. Original neuropsychology studies distinguished separate brain pathways involved in perception and action, known as the dual stream hypothesis. This framework has allowed a better understanding of the deficits identified in Limb Apraxia. In this review, we propose a hierarchical organization of this disorder, in which a distinction can be made between several visuomotor pathways that lead to purposeful actions. Based on this, executive apraxias (such as limb kinetic apraxia) cause deficits in executing fine motor hand skills, and intermediate apraxias (such as optic ataxia and tactile apraxia) cause deficits in reaching to grasp and manipulating objects in space. These disorders usually affect the contralesional limb. A further set of disorders collectively known as limb apraxias include deficits in gesture imitation, pantomime, gesture recognition, and object use. These deficits are due to deficits in integrating perceptual and semantic information to generate complex movements. Limb apraxias are usually caused by left-hemisphere lesions in right-handed stroke patients, affecting both limbs. The anterior- to posterior-axis of brain areas are disrupted depending on the increasing involvement of perceptual and semantic processes with each condition. Lower-level executive apraxias are linked to lesions in the frontal lobe and the basal ganglia, while intermediate apraxias are linked to lesions in dorso-dorsal subdivisions of the dorsal fronto-parietal networks. Limb apraxias can be caused by lesions in both dorsal and ventral subdivisions including the ventro-dorsal stream and a third visuomotor pathway, involved in body schema and social cognition. Rehabilitation of these disorders with behavioral therapies has aimed to either restore perceptuo-semantic deficits or compensate to overcome these deficits. Further studies are required to better stratify patients, using modern neurophysiology and neuroimaging techniques, to provide targeted and personalized therapies for these disorders in the future.

Mental Representations of the Body and Malleability of the Sense of Body Ownership in Schizophrenia within the Embodied Subject Model

The presented study was intended to shed some new light on the disturbance of body experience in persons with schizophrenia in reference to the Embodied Subject Model. The model proposes to complement theoretical linkages between concepts related to bodiness – body self and mental representations of the body (body schema, body image, body awareness) and a relatively new concept of body identity. The main research questions were: Given that persons with schizophrenia are characterised by the painful experience of their body as an external object, would they also manifest i/ weakened sensorimotor integration mechanisms, ii/ disordered mental representations of the body, iii/ weakened sense of body ownership? 41 individuals with schizophrenia and 41 matched controls participated in the Rubber Hand Illusion procedure. Body representations were measured with a Battery of Tests of the Body Self Representations. The individuals with schizophrenia showed lower scores in three body representations and greater susceptibility to the rubber hand illusion. It suggests that the explanation of susceptibility to disturbances in the sense of body ownership should be focused on the deficient structure of mental representations of the body.

Comparison of the Effectiveness of a Special Package for Women with Body Dysmorphic Disorder and Schema Therapy on Metacognitive Beliefs, Identity, and Interpersonal Relationships in Women with Body Dysmorphic Disorder

Comparison of the Effectiveness of a Special Package for Women with Body Dysmorphic Disorder and Schema Therapy on Metacognitive Beliefs, Identity, and Interpersonal Relationships in Women with Body Dysmorphic Disorder

The neuroscience of body memory: Recent findings and conceptual advances.

The body is a very special object, as it corresponds to the physical component of the self and it is the medium through which we interact with the world. Our body awareness includes the mental representation of the body that happens to be our own, and traditionally has been defined in terms of body schema and body image. Starting from the distinction between these two types of representations, the present paper tries to reconcile the literature around body representations under the common framework of body memory. The body memory develops ontogenetically from birth and across all the life span and is directly linked to the development of the self. Therefore, our sense of self and identity is fundamentally based on multisensory knowledge accumulated in body memory, so that the sensations collected by our body, stored as implicit memory, can unfold in the future, under suitable circumstances. Indeed, these sets of bodily information had been proposed as possible key factors underpinning several mental health illnesses. Following this perspective, the Embodied Medicine approach put forward the use of advanced technologies to alter the dysfunctional body memory to enhance people's well-being. In the last sections, recent experimental pieces of evidence will be illustrated that targeted specifically bodily information for increasing health and wellbeing, by means of two strategies: interoceptive feedback and bodily illusions. See also Figure 1(Fig. 1).

Ergonomic evaluation of the chicken hanger workplace in a bird processing company

Introduction: in the poultry processing industry, activities are developed that require the performance of multiple repetitive tasks, generally while standing upright; which increases the risk of developing musculoskeletal disorders in the upper extremities and lower back. These risk factors include: repetitive movements, forced postures, awkward and static postures, vibration and high and low temperatures. Affecting body segments such as neck, shoulders and back. Aim: To ergonomically evaluate the work station: "chicken hanger" of a poultry processing company, in the state of Aragua-Venezuela, during the year 2022. Methods: Quantitative, descriptive, non-experimental, field and cross-sectional research. The population and census sample is constituted by eight (8) workers. In the collection of information, the interview was applied to obtain sociodemographic and labor data, in the description of the work position the documented observation technique was used and for the determination of musculoskeletal discomfort the body schema of pain and the Check List OCRA method were used. Result: the entire population is male, right-handed, average age 33 ±2.67, normal weight, average seniority 4 years ±2.36, with pain at the end of the workday in the shoulder, lower back, upper back and knees. Their Ocra Index was high on the right side and medium on the left side. Conclusion: in the job "chicken hanger" there is a high risk of suffering musculoskeletal disorders in the upper limbs, with greater relevance in the right upper limb

Event-related potentials during mental rotation of body-related stimuli in spinal cord injury population

Mental rotations of body-related stimuli are known to engage the motor system and activate body schema. Sensorimotor deficits following spinal cord injury (SCI) alter the representation of the body with a negative impact on the performance during motor-related tasks, such as mental rotation of body parts. Here we investigated the relationship between event-related potentials in SCI participants and the difficulty in mentally rotating a body-part. Participants with SCI and healthy control subjects performed a laterality judgment task, in which left or right images of hands, feet or animals (as a control stimulus) were presented in two different orientation angles (75° and 150°), and participants reported the laterality of the stimulus. We found that reaction times of participants with SCI were slower for the rotation of body-related stimuli compared to non-body-related stimuli and healthy controls. At the brain level, we found that relative to healthy controls SCI participants show: 1) reduced amplitudes of the posterior P100 and anterior N100 and larger amplitudes of the anterior P200 for overall stimuli; 2) an absence of the modulation of the rotation related negativity by stimulus type and rotation angles. Our results show that body representation changes after SCI affecting both components of early stimulus processing and late components that process high-order cognitive aspects of body-representation and task complexity.