Corporeal illusions in chronic spinal cord injuries

Eliciting the rubber hand illusion by the activation of nociceptive C and Aδ fibers

ABSTRACT

The coherent perceptual experience of one's own body depends on the processing and integration of signals from multiple sensory modalities, including vision, touch, and proprioception. Although nociception provides critical information about damage to the tissues of one's body, little is known about how nociception contributes to own-body perception. A classic experimental approach to investigate the perceptual and neural mechanisms involved in the multisensory experience of one's own body is the rubber hand illusion (RHI). During the RHI, people experience a rubber hand as part of their own body (sense of body ownership) caused by synchronized stroking of the rubber hand in the participant's view and the hidden participant's real hand. We examined whether the RHI can be elicited by visual and "pure" nociceptive stimulation, ie, without tactile costimulation, and if so, whether it follows the basic perceptual rules of the illusion. In 6 separate experiments involving a total of 180 healthy participants, we used a Nd:YAP laser stimulator to specifically target C and Aδ fibers in the skin and compared the illusion condition (congruent visuonociceptive stimulation) to control conditions of incongruent visuonociceptive, incongruent visuoproprioceptive, and no nociceptive stimulation. The illusion was quantified through direct (questionnaire) and indirect (proprioceptive drift) behavioral measures. We found that a nociceptive rubber hand illusion (N-RHI) could be elicited and that depended on the spatiotemporal congruence of visuonociceptive signals, consistent with basic principles of multisensory integration. Our results suggest that nociceptive information shapes multisensory bodily awareness and contributes to the sense of body ownership.

How pain and body representations transform each other: A narrative review

Pain, as a multidimensional and subjective experience, intertwines with various aspects of body representation, involving sensory, affective and motivational components. This review explores the bidirectional relationship between pain and body representations, emphasizing the impact of the sense of ownership on pain perception, the transformative impact of pain on motor imagery, the effects associated with vicarious pain perception on body representations and the role of pain in the maintenance of body representations in specific clinical conditions. Literature indicates complex interactions between pain and body representations, with the sense of ownership inducing analgesic effects in some cases and hyperalgesia in others, contingent upon factors such as the appearance of the affected limb. Pain sensations inform the body on which actions might be executed without harm, and which are potentially dangerous. This information impacts on motor imagery too, showing reduced motor imagery and increased reaction times in tasks where motor imagery involves the painful body parts. Finally, contrary to the conventional view, according to which pain impairs body representation, evidence suggests that pain can serve as an informative somatosensory index, preserving or even enhancing the representation of the absent or affected body parts. This bidirectional relationship highlights the dynamic and multifaceted nature of the interplay between pain and body representations, offering insights into the adaptive nature of the central nervous system in response to perceived bodily states.

Topographic mapping of the sensorimotor qualities of empathic reactivity: A psychophysiological study in people with spinal cord injuries

The experience of empathy for pain is underpinned by sensorimotor and affective dimensions which, although interconnected, are at least in part behaviorally and neurally distinct. Spinal cord injuries (SCI) induce a massive, below-lesion level, sensorimotor body-brain disconnection. This condition may make it possible to test whether sensorimotor deprivation alters specific dimensions of empathic reactivity to observed pain. To explore this issue, we asked SCI people with paraplegia and healthy controls to observe videos of painful or neutral stimuli administered to a hand (intact) or a foot (deafferented). The stimuli were displayed by means of a virtual reality set-up and seen from a first person (1PP) or third person (3PP) visual perspective. A number of measures were recorded ranging from explicit behaviors like explicit verbal reports on the videos, to implicit measures of muscular activity (like EMG from the corrugator and zygomatic muscles that may represent a proxy of sensorimotor empathy) and of autonomic reactivity (like the electrodermal response and Respiratory Sinus Arrhythmia that may represent a general proxy of affective empathy). While no across group differences in explicit verbal reports about the pain stimuli were found, SCI people exhibited reduced facial muscle reactivity to the stimuli applied to the foot (but not the hand) seen from the 1PP. Tellingly, the corrugator activity correlated with SCI participants' neuropathic pain. There were no across group differences in autonomic reactivity suggesting that SCI lesions may affect sensorimotor dimensions connected to empathy for pain.

Interoceptive technologies for psychiatric interventions: From diagnosis to clinical applications

Interoception-the perception of internal bodily signals-has emerged as an area of interest due to its implications in emotion and the prevalence of dysfunctional interoceptive processes across psychopathological conditions. Despite the importance of interoception in cognitive neuroscience and psychiatry, its experimental manipulation remains technically challenging. This is due to the invasive nature of existing methods, the limitation of self-report and unimodal measures of interoception, and the absence of standardized approaches across disparate fields. This article integrates diverse research efforts from psychology, physiology, psychiatry, and engineering to address this oversight. Following a general introduction to the neurophysiology of interoception as hierarchical predictive processing, we review the existing paradigms for manipulating interoception (e.g., interoceptive modulation), their underlying mechanisms (e.g., interoceptive conditioning), and clinical applications (e.g., interoceptive exposure). We suggest a classification for interoceptive technologies and discuss their potential for diagnosing and treating mental health disorders. Despite promising results, considerable work is still needed to develop standardized, validated measures of interoceptive function across domains and before these technologies can translate safely and effectively to clinical settings.

Massive body-brain disconnection consequent to spinal cord injuries drives profound changes in higher-order cognitive and emotional functions: A PRISMA scoping review

Spinal cord injury (SCI) leads to a massive disconnection between the brain and the body parts below the lesion level representing a unique opportunity to explore how the body influences a person's mental life. We performed a systematic scoping review of 59 studies on higher-order cognitive and emotional changes after SCI. The results suggest that fluid abilities (e.g. attention, executive functions) and emotional regulation (e.g. emotional reactivity and discrimination) are impaired in people with SCI, with progressive deterioration over time. Although not systematically explored, the factors that are directly (e.g. the severity and level of the lesion) and indirectly associated (e.g. blood pressure, sleeping disorders, medication) with the damage may play a role in these deficits. The inconsistency which was found in the results may derive from the various methods used and the heterogeneity of samples (i.e. the lesion completeness, the time interval since lesion onset). Future studies which are specifically controlled for methods, clinical and socio-cultural dimensions are needed to better understand the role of the body in cognition.

No reduction in motor-evoked potential amplitude during the rubber hand illusion

INTRODUCTION

In the rubber hand illusion (RHI), touches are applied to a fake hand at the same time as touches are applied to a participant's real hand that is hidden in a congruent position. Synchronous (but not asynchronous) tactile stimulation of the two hands may induce the sensation that the fake hand is the participant's own. As such, the illusion is commonly used to examine the sense of body ownership. Some studies indicate that in addition to the subjective experience of limb ownership reported by participants, the RHI can also reduce corticospinal excitability (e.g., as reflected in motor-evoked potential [MEP] amplitude) and alter parietal-motor cortical connectivity in passive participants. These findings have been taken to support a link between motor cortical processing and the subjective experience of body ownership.

METHODS

In this study, we tried to replicate the reduction in MEP amplitude associated with the RHI and uncover the components of the illusion that might explain these changes. As such, we used single-pulse transcranial magnetic stimulation to probe the excitability of the corticospinal motor system as participants experienced the RHI.

RESULTS

Despite participants reporting the presence of the illusion and showing shifts in perceived real hand position towards the fake limb supporting its elicitation, we did not observe any associated reduction in MEP amplitude.

CONCLUSION

We conclude that a reduction in MEP amplitude is not a reliable outcome of the RHI and argue that if such effects do occur, they are unlikely to be large or functionally relevant.

Altered bodily perceptions in chronic neuropathic pain conditions and implications for treatment using immersive virtual reality

Chronic neuropathic pain is highly disabling and difficult to treat and manage. Patients with such conditions often report altered bodily perceptions that are thought to be associated with maladaptive structural and functional alterations in the somatosensory cortex. Manipulating these altered perceptions using body illusions in virtual reality is being investigated and may have positive clinical implications for the treatment of these conditions. Here, we have conducted a narrative review of the evidence for the types of bodily distortions associated with a variety of peripheral and central neuropathic pain conditions. In addition, we summarize the experimental and clinical studies that have explored embodiment and body transformation illusions in immersive virtual reality for neuropathic pain relief, which are thought to target these maladaptive changes, as well as suggesting directions for future research.

What the study of spinal cord injured patients can tell us about the significance of the body in cognition

Although in the last three decades philosophers, psychologists and neuroscientists have produced numerous studies on human cognition, the debate concerning its nature is still heated and current views on the subject are somewhat antithetical. On the one hand, there are those who adhere to a view implying 'disembodiment' which suggests that cognition is based entirely on symbolic processes. On the other hand, a family of theories referred to as the Embodied Cognition Theories (ECT) postulate that creating and maintaining cognition is linked with varying degrees of inherence to somatosensory and motor representations. Spinal cord injury induces a massive body-brain disconnection with the loss of sensory and motor bodily functions below the lesion level but without directly affecting the brain. Thus, SCI may represent an optimal model for testing the role of the body in cognition. In this review, we describe post-lesional cognitive modifications in relation to body, space and action representations and various instances of ECT. We discuss the interaction between body-grounded and symbolic processes in adulthood with relevant modifications after body-brain disconnection.

Cervical Spinal Lesion, Completeness of Injury, Stress, and Depression Reduce the Efficiency of Mental Imagery in People With Spinal Cord Injury

OBJECTIVES

The aims of this study were to assess the relationships of (1) clinical variables (age, level of injury, time since injury [TSI], and completeness of injury) and (2) psychological variables (stress and depression) with mental imagery ability in individuals with spinal cord injury.

STUDY DESIGN

This was a cross-sectional study. Participants with spinal cord injury (N = 130) were requested to fill the Kinesthetic and Visual Imagery Questionnaire and Vividness of Motor Imagery Questionnaire. They also completed the Perceived Stress Scale and Patient Health Questionnaire 9 for the assessment of stress and depression, respectively.

RESULTS

Mental imagery scores were found to be significantly low in cervical injuries (P < 0.001) as compared with thoracic injuries (P < 0.001). Furthermore, higher levels of spinal injuries resulted in lower mental imagery scores. Completeness of injury (according to Asia Impairment Scale) also had a significant relationship (P < 0.001) with the mental imagery ability among spinal cord injury participants. Presence of stress (P < 0.001) and depression (P < 0.001) also associated with reduced efficiency of mental imagery in these individuals.

CONCLUSIONS

Injury type and psychological factors were associated with mental imagery in SCI patients. Imagery-based interventions should be designed after consideration of identified factors yielding effect on their outcomes.

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CME OBJECTIVES

Upon completion of this article, the reader should be able to: (1) Determine the impact of clinical variables such as level of injury, completeness and chronicity of injury on mental imagery ability in spinal cord injury; (2) Discuss the role of stress and depression on mental imagery ability in spinal cord injury; and (3) Describe the various dimensions of mental imagery ability and its variability among individuals who have spinal cord injury.

LEVEL

Advanced.

ACCREDITATION

The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Body Representation in Patients with Severe Spinal Cord Injury: A Pilot Study on the Promising Role of Powered Exoskeleton for Gait Training

Patients with spinal cord injury (SCI) complain of changes in body representation, potentially leading to negative physical and psychological consequences. The purpose of our study is to evaluate the effects of robotic training with the Ekso-GT on body representation (BR) and on the quality of life in patients with SCI. The trial was designed as a pilot, assessor-blinded study. Forty-two inpatients with a diagnosis of SCI, classified as either American Spinal Cord Injury Association Impairment Scale (AIS), were enrolled in this study and randomized into either a control (CG: n = 21) or an experimental (EG: n = 21) group. Patients in the EG received rehabilitation training with the Ekso-GT device, whereas the CG patients were trained with conventional physical therapy (CPT), which consisted of physical and occupational therapy and psychological support. We considered as a primary outcome the modified Body Uneasiness Test (MBUT), focusing on three specific subscales on the patient’s perception of BR, i.e., the Global Severity Index (MBUT-GSI), which is an indicator of body suffering; the Positive Symptom Distress Index (MBUT-PSDI) that expresses an individual’s psychological distress; and the Lower Limb MBUT (MBUT-LL), which indicates the subject’s perception of their thighs/legs. The Short-Form-12 Health Status Questionnaire (SF12) and the Beck’s Depression Inventory (BDI) were used as secondary outcomes to evaluate the effect of the training on the quality of life and the psychological status. Non-parametric statistical analysis showed that the effect of the two treatments was significantly different on MBUT (BR), SF-12 (quality of life), and, partially, BDI (mood). Particularly, patients belonging to the EG achieved a major improvement in nearly all test scores compared to those in the CG. Our data suggest that the Ekso-GT training could be helpful in achieving positive changes in BR in patients with chronic SCI, especially in reducing psychological distress (PSDI) and thigh/leg perception (MBUT-LL) with an overall improvement in quality of life (SF-12).

Bodily Illusions and Motor Imagery in Fibromyalgia

Fibromyalgia (FM) is characterised by chronic, continuous, widespread pain, often associated with a sense of fatigue, non-restorative sleep and physical exhaustion. Due to the nature of this condition and the absence of other neurological issues potentially able to induce disorders in body representations per se, it represents a perfect model since it provides an opportunity to study the relationship between pain and the bodily self. Corporeal illusions were investigated in 60 participants with or without a diagnosis of FM by means of an ad hoc devised interview. In addition, motor imagery was investigated and illusions relating to body part movements and changes in body size, feelings of alienness, and sensations of body parts not belonging to one's own body (disownership and somatoparaphrenic-like sensations) were found. Crucially, these symptoms do not correlate with any of the clinical measures of pain or functional deficits. The results showed that motor imagery was also impaired, and the severity of the deficits found correlated with the functional impairment of the participant. This indicates that disorders in body representations and motor imagery are part of the clinical expression of FM. However, while motor imagery seems to be linked to reduced autonomy and functional deficits, bodily illusions are independent and potentially represent a concurrent symptom.

Cognitive Training Improves Disconnected Limbs' Mental Representation and Peripersonal Space after Spinal Cord Injury

Paraplegia following spinal cord injury (SCI) affects the mental representation and peripersonal space of the paralysed body parts (i.e., lower limbs). Physical rehabilitation programs can improve these aspects, but the benefits are mostly partial and short-lasting. These limits could be due to the absence of trainings focused on SCI-induced cognitive deficits combined with traditional physical rehabilitation. To test this hypothesis, we assessed in 15 SCI-individuals the effects of adding cognitive recovery protocols (motor imagery–MI) to standard physical rehabilitation programs (Motor + MI training) on mental body representations and space representations, with respect to physical rehabilitation alone (control training). Each training comprised at least eight sessions administered over two weeks. The status of participants’ mental body representation and peripersonal space was assessed at three time points: before the training (T0), after the training (T1), and in a follow-up assessment one month later (T2). The Motor + MI training induced short-term recovery of peripersonal space that however did not persist at T2. Body representation showed a slower neuroplastic recovery at T2, without differences between Motor and the Motor + MI. These results show that body and space representations are plastic after lesions, and open new rehabilitation perspectives.

Little evidence for an effect of the rubber hand illusion on basic movement

Body ownership refers to the distinct sensation that our observed body belongs to us, which is believed to stem from multisensory integration. This is commonly shown through the rubber hand illusion (RHI), which induces a sense of ownership over a false limb. Whilst the RHI may interfere with object-directed action and alter motor cortical activity, it is not yet clear whether a sense of ownership over an artificial hand has functional consequences for movement production per se. As such, we performed two motion-tracking experiments (n = 117) to examine the effects of the RHI on the reaction time, acceleration, and velocity of rapid index finger abduction. We observed little convincing evidence that the induction of the RHI altered these kinematic variables. Moreover, the subjective sensations of rubber hand ownership, referral of touch, and agency did not convincingly correlate with kinematic variables, and nor did proprioceptive drift, suggesting that changes in body representation elicited by the RHI may not influence basic movement. Whilst experiment 1 suggested that individuals reporting a greater sensation of the real hand disappearing performed movements with smaller acceleration and velocity following illusion induction, we did not replicate this effect in a second experiment, suggesting that these effects may be small or not particularly robust. Overall, these results indicate that manipulating the conscious experience of body ownership has little impact on basic motor control, at least in the RHI with healthy participants.

Awareness of voluntary action, rather than body ownership, improves motor control

Awareness of the body is essential for accurate motor control. However, how this awareness influences motor control is poorly understood. The awareness of the body includes awareness of visible body parts as one’s own (sense of body ownership) and awareness of voluntary actions over that visible body part (sense of agency). Here, I show that sense of agency over a visible hand improves the initiation of movement, regardless of sense of body ownership. The present study combined the moving rubber hand illusion, which allows experimental manipulation of agency and body ownership, and the finger-tracking paradigm, which allows behavioral quantification of motor control by the ability to coordinate eye with hand movements. This eye–hand coordination requires awareness of the hand to track the hand with the eye. I found that eye–hand coordination is improved when participants experience a sense of agency over a tracked artificial hand, regardless of their sense of body ownership. This improvement was selective for the initiation, but not maintenance, of eye–hand coordination. These results reveal that the prospective experience of explicit sense of agency improves motor control, suggesting that artificial manipulation of prospective agency may be beneficial to rehabilitation and sports training techniques.

Mental Imagery as a Rehabilitative Therapy for Neuropathic Pain in People With Spinal Cord Injury: A Randomized Controlled Trial

BACKGROUND

Pain of neuropathic origin in spinal cord injury (SCI) is unbearable and challenging to treat. Research studies conducted in the past have shown that mental imagery (MI) techniques have a significant impact on the reduction of symptoms of central neuropathic pain in people with SCI.

OBJECTIVES

The objective of this study was to evaluate the effect of MI training on pain intensity, neuropathic pain symptoms, and interference of pain with function in SCI.

METHODS

A total of 42 SCI participants with central neuropathic pain (duration 6-12 months) were recruited and randomly allocated to MI or control groups. A MI training protocol was administered to MI group and for 30 min/d for 5 days. Outcome measures were assessed at baseline and at the end of 4 weeks.

RESULTS

There was significant reduction in differences of mean [95% CI] scores of numeric rating scale (-2.1 [CI -2.78 to -1.41]; P < .001) between groups. Mean [95% CI] total scores of Neuropathic Pain Symptom Inventory declined in MI group as compared with control group (-4.52 [CI -5.86 to -3.18]; P < .001). Similarly, Brief Pain Inventory interference scale total dropped significantly (P < .001) in MI group. Majority of participants in the MI group (55%) reported improvement in scores of Patients' Global Impression of Change scale as compared with control group where most of the participants (52%) reported no change.

CONCLUSIONS

This study shows the effectiveness of the MI protocol developed as a rehabilitative approach in improving central neuropathic pain in SCI. Trial Registration. Clinical Trials Registry-India under Indian Council of Medical Research; CTRI/2018/07/014884. Registered July 16, 2018.

Imagined paralysis alters somatosensory evoked-potentials

Recent studies employing body illusions have shown that multisensory conflict can alter body representations and modulate low-level sensory processing. One defining feature of these body illusions is that they are sensory driven and thus passive on behalf of the participant. Thus, it remained to establish whether explicit alteration of own-body representations modulates low-level sensory processing. We investigated whether tibial nerve somatosensory-evoked potentials were modulated when participants imagined paralysis of their legs and arms. Imagined paralysis of the legs decreased P40 amplitude, but not imagined paralysis of the arms. These results show modulation of early somatosensory processing via explicit, top-down alteration to the internal representation of the body. Interestingly, P40 suppression positively correlated with bodily awareness scores whereas it negatively correlated with body dissociation scores. This suggests that the ability to actively alter own-body representation and its corresponding sensory processing depends upon dispositions to attend to and focus on bodily sensations.

Visuo-motor and interoceptive influences on peripersonal space representation following spinal cord injury

Peripersonal space (PPS) representation is modulated by information coming from the body. In paraplegic individuals, whose lower limb sensory-motor functions are impaired or completely lost, the representation of PPS around the feet is reduced. However, passive motion can have short-term restorative effects. What remains unclear is the mechanisms underlying this recovery, in particular with regard to the contribution of visual and motor feedback and of interoception. Using virtual reality technology, we dissociated the motor and visual feedback during passive motion in paraplegics with complete and incomplete lesions and in healthy controls. The results show that in the case of paraplegics, the presence of motor feedback was necessary for the recovery of PPS representation, both when the motor feedback was congruent and when it was incongruent with the visual feedback. In contrast, visuo-motor incongruence led to an inhibition of PPS representation in the control group. There were no differences in sympathetic responses between the three groups. Nevertheless, in individuals with incomplete lesions, greater interoceptive sensitivity was associated with a better representation of PPS around the feet in the visuo-motor incongruent conditions. These results shed new light on the modulation of PPS representation, and demonstrate the importance of residual motor feedback and its integration with other bodily information in maintaining space representation.

Anosognosia for limb and bucco-facial apraxia as inferred from the recognition of gestural errors

Anosognosia is a multifaceted syndrome characterized by a lack of awareness of motor, cognitive, or emotional deficits. While most studies have focused on basic motor disorders such as hemiplegia, only recently, the issue of whether anosognosia also concerns higher-order motor disorders like apraxia has been addressed. Here, we explore the existence of a specific form of anosognosia for apraxia in forty patients with uni-hemispheric vascular lesions. The patients were requested to imitate actions involving upper limb or bucco-facial body parts and then judge their performance. Successively, they were also asked to observe video recordings of the same actions performed by themselves or by other patients and judge the accuracy of the displayed actions. The comparison of participants versus examiner judgement and between error recognition of others' versus self's actions was considered as an index of awareness deficit for the online and offline conditions, respectively. Evidence was found that awareness deficits occurred both immediately after action execution (online anosognosia) and in the video recording task (offline anosognosia). Moreover, bucco-facial and limb apraxic patients were specifically unaware of their errors in bucco-facial and limb actions, respectively, indicating for the first time a topographical organization of the syndrome. Our approach allowed us to distinguish awareness deficits from more general disorders in error recognition; indeed, anosognosic patients were able to identify errors when the same action was executed by another patient but not when the video showed their own actions. Finally, we provide evidence that anosognosia for apraxia might be associated with frontal cortical and subcortical networks.

Weakening the subjective sensation of own hand ownership does not interfere with rapid finger movements

When we perform a movement we generally have a clear distinction between which parts of the world constitute our body and which parts do not. However, how the sense of ownership over our body supports movement is not yet fully understood. We aimed to see whether a sense of ownership over the hand supports the performance of rapid hand movements. In three experiments (n = 48, n = 30, n = 24), we presented participants with congruent and incongruent visuotactile and visuoproprioceptive information regarding their own hand. In keeping with previous experiments, multisensory disintegration resulted in a reduction in the subjective sensation of ownership over the hand, as reflected in questionnaire responses. Following sensory stimulation, participants were required to rapidly abduct their index finger whilst the movement was tracked. We examined the hypothesis that, should a sense of ownership over the limb be necessary for generating rapid movements with that limb, reaction time would increase when hand ownership was reduced, whilst the acceleration and velocity of the movement would decrease. We observed that reductions in own hand ownership did not interfere with rapid index finger abduction, suggesting that the motor system may not be reliant on a subjective sense of ownership over the body in order to generate movement.

Anticipation of wheelchair and rollerblade actions in spinal cord injured people, rollerbladers, and physiotherapists

Embodied Cognition Theories (ECT) postulate that higher-order cognition is heavily influenced by sensorimotor signals. We explored the active role of somatosensory afferents and motor efferents in modulating the perception of actions in people who have suffered a massive body-brain disconnection because of spinal cord injury (SCI), which leads to sensory-motor loss below the lesion. We assessed whether the habitual use of a wheelchair enhances the capacity to anticipate the endings of tool-related actions, with respect to actions that have become impossible. In a Temporal Occlusion task, three groups of participants (paraplegics, rollerbladers and physiotherapists) observed two sets of videos depicting an actor who attempted to climb onto a platform using a wheelchair or rollerblades. Three different outcomes were possible, namely: a) success (the actor went up the step); b) fail (the actor stopped before the step without going up) and c) fall (the actor fell without going up). Each video set comprised 5 different durations increasing in complexity: in the shortest (600ms) only preparatory body movements were shown and in the longest (3000ms) the complete action was shown. The participants were requested to anticipate the outcome (success, fail, fall). The main result showed that the SCI group performed better with the wheelchair videos and poorer with rollerblade videos than both groups, even if the physiotherapists group never used rollerblades. In line with the ECT, this suggests that the action anticipation skills are not only influenced by motor expertise, but also by motor connection.

Dissociation between preserved body structural description and impaired body image following a pediatric spinal trauma

In adult patients, Spinal Cord Injury (SCI) may influence the mental Body Representation (BR). Currently, there is no evidence on the modulation of SCI on BR during early stages of cognitive development. Here, we investigated BR in a 3-year-old child with complete SCI. The patient was administered with a specific battery assessing different BR components. We found evidence for putative classical neuropsychological dissociation between a preserved topological map with impaired semantic knowledge of the body. This finding sheds new light on the impact of SCI on BR in childhood, as well as on the level of interdependence between BR's components..