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Spinal cord injury can cause cognitive impairments even when no cerebral lesion is appreciable. As patients are forced to explore the environment in a non‐canonical position (i.e., seated on a wheelchair), a modified relation with space can explain motor‐related cognitive differences compared to non‐injured individuals. Peripersonal space is encoded in motor terms, that is, in relation to the representation of action abilities and is strictly related to the affordance of reachability. In turn, affordances, the action possibilities suggested by relevant properties of the environment, are related to the perceiver's peripersonal space and motor abilities. One might suppose that these motor‐related cognitive abilities are compromised when an individual loses the ability to move. We shed light on this issue in 10 patients with paraplegia and 20 matched controls. All have been administered an affordances‐related reachability judgement task adapted from Costantini, Ambrosini, Tieri, Sinigaglia, and Committeri (2010, Experimental Brain Research, 207, 95) and neuropsychological tests. Our findings demonstrate that patients and controls show the same level of accuracy in estimating the location of their peripersonal space boundaries, but only controls show the typical overestimation of reaching range. Secondly, patients show a higher variability in their judgements than controls. Importantly, this finding is related to the patients' ability to perform everyday tasks. Finally, patients are not faster in making their judgements on reachability in peripersonal space, while controls are. Our results suggest that not moving freely or as usual in the environment impact decoding of action‐related properties even when the upper limbs are not compromised. [ABSTRACT FROM AUTHOR]

Sensory events contribute to body ownership, the feeling that the body belongs to me. However, the encoding of sensory events is not only reactive, but also proactive in that our brain generates prediction about forthcoming stimuli. In previous studies, we have shown that prediction of sensory events is a sufficient condition to induce the sense of body ownership. In this study, we investigated the underlying neural mechanisms. Participants were seated with their right arm resting upon a table just below another smaller table. Hence, the real hand was hidden from the participant's view and a life-sized rubber model of a right hand was placed on the small table in front of them. Participants observed a wooden plank while approaching - without touching - the rubber hand. We measured the phenomenology of the illusion by means of questionnaire. Neural activity was recorded by means of near-infrared spectroscopy ( fNIRS). Results showed higher activation of multisensory parietal cortices in the rubber hand illusion induced by touch expectation. Furthermore, such activity was correlated with the subjective feeling of owning the rubber hand. Our results enrich current models of body ownership suggesting that our multisensory brain regions generate prediction on what could be my body and what could not. This finding might have interesting implications in all those cases in which body representation is altered, anorexia, bulimia nervosa and obesity, among others. [ABSTRACT FROM AUTHOR]

Perceiving a body is a phenomenal experience completely different from experiencing a body as one's own body. Visual presentation of bodies or body parts recruits several occipitotemporal regions in the brain. Are these activations sufficient in order to change the phenomenal status of a body in one's own body? In this paper, I will review consolidated experimental evidence showing that the feeling of owning a body is not limited to the vision of a body, rather it is the result of a complex interaction between interoception, exteroception, and pre-existing body templates. To illustrate this complex interplay, I will take advantage of the so-called bodily illusions, referring to controlled illusory generation of unusual bodily feeling. These feelings include having a supernumerary limb, or lacking an arm, or feeling like you do not really have a body, or feeling that you do not really control a certain part of your body, or that your body is not really yours. In the last 15 years more than 150 empirical studies on body illusions have been published (Source: Pubmed, June 2014). These studies, using different technologies, are largely responsible for contributed our current understanding of bodily self-consciousness. [ABSTRACT FROM AUTHOR]

Request and emblematic gestures, despite being both communicative gestures, do differ in terms of social valence. Indeed, only the former are used to initiate/maintain/terminate an actual interaction. If such a difference is at stake, a relevant social cue, i.e. eye contact, should have different impacts on the neuronal underpinnings of the two types of gesture. We measured blood oxygen level-dependent signals, using functional magnetic resonance imaging, while participants watched videos of an actor, either blindfolded or not, performing emblems, request gestures, or meaningless control movements. A left-lateralized network was more activated by both types of communicative gestures than by meaningless movements, regardless of the accessibility of the actor's eyes. Strikingly, when eye contact was taken into account as a factor, a right-lateralized network was more strongly activated by emblematic gestures performed by the non-blindfolded actor than by those performed by the blindfolded actor. Such modulation possibly reflects the integration of information conveyed by the eyes with the representation of emblems. Conversely, a wider right-lateralized network was more strongly activated by request gestures performed by the blindfolded than by those performed by the non-blindfolded actor. This probably reflects the effect of the conflict between the observed action and its associated contextual information, in which relevant social cues are missing. [ABSTRACT FROM AUTHOR]

Neuroimaging studies report that the experience of observing or imagining the pain of others is mapped on a set of neural structures that largely overlap those called into play during the personal experience of pain (the so-called pain matrix). Empathy for pain is a multifaceted process that may be triggered by higher-order variables (such as imagination of others’ suffering) or by the direct vision of painful situations. Most functional magnetic resonance imaging studies indicate that the empathic mapping of others’ pain may rely on the affective and not on the sensorimotor division of the pain matrix. However, as empathy for pain is a complex, multifarious process, it is possible that different brain regions, even beyond the classic pain matrix, may be called into action in different circumstances. By using functional magnetic resonance imaging we explored the neural activity induced by needles deeply penetrating a hand or a non-corporeal object. We found that observation of pain in others brought about activation in the middle cingulate, left premotor and left and right supramarginal regions. This pattern of neural activity indicates that the direct vision of strong painful stimuli delivered to others activates neural regions in the onlooker’s brain specifically concerned with the resonant, interindividual sharing of basic sensorimotor reactivity to pain. We also found that bilateral posterior parietal and temporo-occipital regions were activated during observation of painful stimuli delivered to the body of others as well as to non-body stimuli. Therefore, our study expands current knowledge on the neural reactivity to potentially dangerous stimuli delivered in the peripersonal space. [ABSTRACT FROM AUTHOR]