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According to the dimensional approach to psychosis, there is a continuum from low schizotypy to schizophrenia patients. The temporal aspect of sensory processing seems to be compromised across such continuum, as suggested by different studies separately investigating unisensory or multisensory domains. Most of these studies have so far focused primarily on the temporal processing of visual and auditory stimuli, either in schizotypy or schizophrenia, while leaving the tactile domain and the integration of touch with other senses mostly unexplored. Given the relevance of body-related perceptual abnormalities for psychosis proneness, we aimed at filling this gap in the literature across two studies. We asked participants with increasing levels of schizotypy (study 1) and schizophrenia patients (study 2) to perform three simultaneity judgement tasks: a unimodal tactile task, a unimodal auditory task and a bimodal audio-tactile task. Each task allowed estimating a simultaneity range (SR), as a proxy of the individual tolerance to asynchronies in the tactile, auditory and audio-tactile domains, respectively. Results showed larger SRs as the level of schizotypy increases. Specifically, the linear effect of schizotypy levels on the audio-tactile task was stronger than on the auditory task, which in turn was greater than the effect on the tactile task (study 1). Differently, schizophrenia patients showed larger SRs than controls in all the three tasks (study 2). The current study is the first empirical investigation across the continuum from low schizotypy to schizophrenia of the tolerance to asynchronies in the processing of external (auditory) and body-related (tactile) inputs. [ABSTRACT FROM AUTHOR]

• Multisensory integration, body representation, and pain are often linked. • Neural changes in SCI may influence multisensory integration and body representation. • Neuropathic pain in SCI may be partially related to deficits in multisensory body representation. • Multisensory integration and body representation in SCI are novel fields of study. • Multisensory trainings may be beneficial to prevent maladaptive brain reorganization. In this review we focus on maladaptive brain reorganization after spinal cord injury (SCI), including the development of neuropathic pain, and its relationship with impairments in body representation and multisensory integration. We will discuss the implications of altered sensorimotor interactions after SCI with and without neuropathic pain and possible deficits in multisensory integration and body representation. Within this framework we will examine published research findings focused on the use of bodily illusions to manipulate multisensory body representation to induce analgesic effects in heterogeneous chronic pain populations and in SCI-related neuropathic pain. We propose that the development and intensification of neuropathic pain after SCI is partly dependent on brain reorganization associated with dysfunctional multisensory integration processes and distorted body representation. We conclude this review by suggesting future research avenues that may lead to a better understanding of the complex mechanisms underlying the sense of the body after SCI, with a focus on cortical changes. [ABSTRACT FROM AUTHOR]

Abstract: Previous evidence has shown that active tool-use remaps agents’ reaching space with far objects being perceived as reachable and graspable. To date, however, there is no evidence that tool-use observation might also be effective in reaching space remapping. The present six experiments show that not only performing but also observing tool actions may extend the representation of reaching space, useful for grasping objects. In addition, like active tool-use, tool-use observation also impacts on visual distance judgment. Interestingly, these effects only occurred when observers shared the same action potentialities with the agent, i.e., while passively holding a tool compatible with the goal and the spatial range of the observed action. The present findings demonstrate that observing someone else acting with a tool may actually shape the way we map the objects and the space around us, suggesting that such a mapping could provide us with a keystone for coordinating and integrating our actions with those of others. [Copyright &y& Elsevier]

Abstract: Although vision is the primary sensory modality that humans and other primates use to identify objects in the environment, we can recognize crucial object features (e.g., shape, size) using the somatic modality. Previous studies have shown that the occipito-temporal areas dedicated to the visual processing of object forms, faces and bodies also show category-selective responses when the preferred stimuli are haptically explored out of view. Visual processing of human bodies engages specific areas in lateral (extrastriate body area, EBA) and medial (fusiform body area, FBA) occipito-temporal cortex. This study aimed at exploring the relative involvement of EBA and FBA in the haptic exploration of body parts. During fMRI scanning, participants were asked to haptically explore either real-size fake body parts or objects. We found a selective activation of right and left EBA, but not of right FBA, while participants haptically explored body parts as compared to real objects. This suggests that EBA may integrate visual body representations with somatosensory information regarding body parts and form a multimodal representation of the body. Furthermore, both left and right EBA showed a comparable level of body selectivity during haptic perception and visual imagery. However, right but not left EBA was more activated during haptic exploration than visual imagery of body parts, ruling out that the response to haptic body exploration was entirely due to the use of visual imagery. Overall, the results point to the existence of different multimodal body representations in the occipito-temporal cortex which are activated during perception and imagery of human body parts. [Copyright &y& Elsevier]

Abstract: Several studies on humans have shown a recruitment of the sensory-motor system in the perception of action-related visual and verbal material, suggesting that actions are represented through sensory-motor processes. To date, these studies have not disentangled whether such a recruitment is epiphenomenal or necessary to action representation. Here we took advantage of repetition priming as a tool to investigate the cognitive representation of actions, and systematically looked whether a concurrent motor or verbal task had a detrimental effect on this representation. In a first experiment participants discriminated images depicting meaningless and meaningful actions, while performing either a concurrent sensory-motor or an articulatory suppression task. Images were classified as depicting a repeated or a new action, relative to the previous image in the trial series. We found a facilitation by repetition priming, that was unaffected by the articulatory task but was completely abolished by the sensory-motor task. In a second experiment, we investigated whether the sensory-motor system is also causally involved in processing action-related verbs. In this experiment actions were presented as written infinitive verbs rather than as images. The facilitation by repetition priming was again unaffected by the concurrent articulatory task, while the sensory-motor concurrent task, although reducing the facilitation, did not abolish it. Our data provide evidence that the sensory-motor system is differentially involved during visual processing of actions and during processing of action-related verbs. Results are discussed within the theoretical frame of embodied cognition. [Copyright &y& Elsevier]

Abstract: We constantly feel, see and move our body, and have no doubt that it is our own. The brain possesses a distinction between the body and the objects in the outside world. This distinction may be based on a process that monitors whether sensations, events and objects should be attributed to one''s body or not. We controlled whether an external object was represented as part of the body or not, by experimentally inducing a bodily illusion using correlated visual and tactile stimulation. We then studied the role of right temporo-parietal junction (rTPJ) in the processing of multisensory events that may or may not be attributed to one''s body. Disruption of rTPJ using transcranial magnetic stimulation (TMS) made the distinction between what may or may not be part of one''s body on the basis of multisensory evidence more ambiguous, suggesting that the rTPJ is actively involved in maintaining a coherent sense of one''s body, distinct from external, non-corporeal, objects. [Copyright &y& Elsevier]

The influence of ipsilesional tactile and visual stimuli on the ability to detect contralesional tactile stimuli was investigated in eight right brain damaged patients (RBD) with tactile extinction and in eight healthy subjects by delivering a series of single and double stimuli. Double stimuli were unimodal (tactile or visual) or cross-modal (tactile and visual) and could be delivered simultaneously or sequentially at three possible intervals (65, 125, 305 ms). In sequential double trials, left-sided stimuli preceded or followed right-sided stimuli. Subjects were asked to verbally report number (1 or 2), side (left or right) and modality (tactile, visual, visuo-tactile). Control subjects were highly accurate in detecting single and double stimuli. RBD patients detected all right-sided stimuli and left single visual or tactile stimuli with high accuracy; however, they omitted left-sided tactile stimuli in a high proportion of double trials due to the presence of tactile extinction.Omissions of left-sided tactile stimuli were minimal at the longest SOA. Moreover, at 0 and 65 ms SOA omissions were significantly higher in unimodal than in cross-modal combinations. This figure indicates that detection of contralesional tactile stimuli is modulated over time both uni- and cross-modally. [Copyright &y& Elsevier]

The peripersonal space (PPS) is a multisensory and sensorimotor interface between our body and the environment. The location of PPS boundary is not fixed. Rather, it adapts to the environmental context and differs greatly across individuals. Recent studies have started to unveil the neural correlates of individual differences in PPS extension; however, this picture is not clear yet. Here, we used approaching auditory stimuli and magnetoencephalography to capture the individual boundary of PPS and examine its neural underpinnings. In particular, building upon previous studies from our own group, we investigated the possible contribution of an intrinsic feature of the brain, that is the "resting state" functional connectivity, to the individual differences in PPS extension and the frequency specificity of this contribution. Specifically, we focused on the activity synchronized to the premotor cortex, where multisensory neurons encoding PPS have been described. Results showed that the stronger the connectivity between left premotor cortex (lPM) and a set of fronto-parietal, sensorimotor regions in the right and left hemisphere, the wider the extension of the PPS. Strikingly, such a correlation was observed only in the beta-frequency band. Overall, our results suggest that the individual extension of the PPS is coded in spatially- and spectrally-specific resting state functional links. • Resting state functional connectivity contributes to individual differences in PPS extension. • Wider PPS is linked to stronger synchronization between lPM and bilateral sensorimotor cortices. • MEG synchronization patterns relevant to individual PPS are specifically observed in the beta-frequency band. • Our results support the notion of PPS extension as a "trait-like" feature of the individual. [ABSTRACT FROM AUTHOR]

Abstract: A 66-year-old patient with a recent history of chest pain was submitted to exercise test. The rest electrocardiogram was normal, but during effort, a striking U-wave inversion in the chest leads occurred, not associated with any ST-segment change. Coronary angiogram demonstrated a severe proximal narrowing of the left anterior descending coronary artery. Effort-induced U-wave inversion in the precordial leads has long been recognized as a marker of stenosis of the left anterior descending coronary artery, but this pattern is seldom taken into account. [Copyright &y& Elsevier]

Acute myocarditis may mimic an infarction. Aim is to describe a case series of peculiar myocarditis. From 1997 to 2003, 11 male patients (age 17–39 years) were admitted with diagnosis of acute myocardial infarction, localized ST segment elevation and minimal enzyme release. Ten patients had fever in the 3 days prior to admission. Eight patients underwent coronary angiography showing normal coronary arteries. All remained asymptomatic at long term follow-up. In conclusion, myocarditis with ST elevation myocardial infarction presentation is an acute benign syndrome especially frequent in young males. [Copyright &y& Elsevier]

Abstract: Previous studies have shown a motor recruitment during the observation of graspable objects. This recruitment has been considered crucial in encoding the observed objects in terms of one or more potential motor acts. However, an agent can actually act upon an object only when the latter is close enough to be reached. Thus, the question we deal with in this paper is whether the motor system is always activated whenever a graspable object comes into view or whether it requires the object to be located within the reachable space of the perceiver. The left primary motor cortex was magnetically stimulated and motor evoked potentials (MEPs) were recorded while participants observed graspable and non graspable objects located within or outside their own reachable space. We found higher MEPs during the observation of graspable objects falling within the reachable space compared to the observation of either a non graspable object or a graspable object falling outside the reachable space. Our results shed new light on the functional role of the motor system in encoding visually presented objects. Indeed, they clearly indicate that its recruitment is spatially constrained, as it depends on whether the object falls within the actual reaching space of the onlooker. [Copyright &y& Elsevier]

In order to survive in a complex environment, inhabited by potentially threatening and noxious objects or living beings, we need to constantly monitor our surrounding space, especially in the vicinity of our body. Such a space has been commonly referred to as one's ‘peripersonal space’ (PPS). In this study we investigated whether emotion-inducing approaching sound sources impact the boundaries of PPS. Previous studies have indeed showed that the boundaries of PPS are not fixed but modulate according to properties of stimuli in the surrounding environment. In Experiment 1, participants performed a simple tactile detection task of targets presented to their right hand. Concurrently, they were presented with intensity-changing task-irrelevant artificial sound sources perceived as approaching toward their body. The physical properties of the sound elicited emotional responses of either neutral or negative valence. Results showed larger PPS when the approaching stimulus had negative as compared to neutral emotional valence. In Experiment 2, we used ecological sounds which content (i.e., psychological associations to the sound producing source), rather than physical properties, elicited emotional responses of negative, positive or neutral valence. In agreement with results from experiment 1, we found larger PPS when the approaching stimuli had negative emotional valence as compared to both neutral and positive ones. Results are discussed within the theoretical framework that conceives PPS as a safety zone around one’s body. [ABSTRACT FROM AUTHOR]

Abstract: In this study we investigated whether objects and their name evoke the activation of the same motor programs. In the first experiment participants had to make speeded responses based on the category of an object. They had to signal whether an object, presented visually, either within or outside their reachable space, was natural or manufactured, by making reach-to-precision or reach-to-power grasp responses. We found a compatibility effect between the response required by task, and the grip evoked by the object, for reachable space only. Nevertheless, this finding holds for artefacts and not for natural objects. In the second experiment, participants had to make reach-to-precision or reach-to-power grasp responses when deciding whether an object, presented either within or outside their reachable space, was congruent with a previously displayed word. In this case we found a compatibility effect between the response required by task and the grip evoked by the object''s name, however this effect was not limited by participants’ reaching range. Our data suggest that objects and objects’ name likely correspond to different motor representations. That is, while the former seem to house both stable (i.e., shape and size) and temporary (i.e., orientation and distance with respect to the perceiver) action-relevant information, the latter seem to house only stable action-relevant information. [Copyright &y& Elsevier]