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The space surrounding our body, defined as peripersonal space (PPS), is dynamically shaped by our motor experiences. For instance, PPS extends after using a tool to reach far objects. Several studies have demonstrated how PPS size varies across people, depending on different individual characteristics, including schizotypy. Coherently, narrower PPS boundaries have been reported among high schizotypal individuals and schizophrenia patients. However, little is known about the relationship between PPS plasticity and personality traits like schizotypy. To this purpose, the present study has investigated the individual PPS plasticity, after two different motor trainings, along the schizotypal continuum. Specifically, PPS plasticity was tested after using a tool (Experiment 1) and after the mere observation of another person using the same tool (Experiment 2). Indeed, previous evidence has shown that tool-use observation influences visual distance judgments, extending the representation of PPS. To date, however, there is no study investigating whether observation of tools action could also affect multisensory PPS tasks. Experiment 1 has shown that PPS boundaries extended after using the tool; on the other hand, Experiment 2 has revealed the absence of PPS expansion. Moreover, greater PPS expansion emerged in the relatively-low schizotypal group than in the relatively-high one, regardless of the type of motor training performed. The absence of PPS modulation after the observation task is discussed in relation to recent findings showing that intentional action and/or the goal of the action represent potentially crucial elements to trigger PPS plasticity. Finally, these new results extend previous evidence underlining a potential general functional alteration of PPS with the increase of schizotypal level., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Previous research has reported that the perception of written language symbols activates the cortical motor hand representation of the dominant hemisphere also found to be activated during the writing of these symbols. It has been suggested that such motor activation supports reading. Nevertheless, the precise circumstances leading to such activation are still unknown. For instance, several studies suggested that motor activation necessarily depends on specific sensory-motor experience with the stimuli. Some results, however, also indicated that untrained stimuli can elicit the response. Moreover, due to the methods used so far, little is known about the temporal course of the motor activity. Our study explored these open questions using high-density EEG. We measured central alpha event-related desynchronization (ERD) as a marker of cortical motor activation during the observation of Roman letters (alphabet of participants' mother language), Chinese characters (not familiar to participants), and scribbles. Our results show that the cortical motor system is activated during the perception of all three stimuli in both hemispheres, with ERD stronger in the left (dominant) hemisphere. A significant difference of ERD time-course was observed in the left hemisphere between the observation of symbols (letters and characters) and scribbles. Scribbles elicited significantly faster resynchronization of central alpha than symbols. We suggest that ERD results are due to recognizing all stimuli as traces of hand gestures. Furthermore, differences in ERD found between symbols and scribbles might depend either on visuo-motor training, separating symbols from scribbles, or on stimuli specific features marking their status as either language symbols or scribbles., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Schizophrenia is often associated with deficits in the domain of language, which are thought to be closely related to deficits in the structure of semantic knowledge. The main aim of the present study was to behaviorally investigate whether semantic impairments in schizophrenia are present also at the very basic level of action verb processing, in particular at the level of motor simulation. We used a go-no go paradigm both for a semantic decision task (with either an early, EGD, or a delayed go-signal delivery, DGD) and for a lexical decision task (control task). Only the first task requires motor simulation to be solved. We found that first-episode schizophrenia (FES) patients, like healthy control (HC) participants, use motor simulation as a basic strategy to semantically judge action verbs. In the EGD condition, both motor simulation and action verb understanding seem to be preserved in FES. However, differently from HC participants, FES patients kept on using the simulation strategy also with the DGD condition, whereas, simultaneously, task performance during this condition appeared to be less efficient and sensitive. Voxel-based morphometry analysis suggested that this altered performance in FES patients could be related to structural brain abnormalities in the right dorsolateral prefrontal cortex. We propose that a prolonged motor simulation in FES may serve as a compensatory strategy for impairments in the selection of action representation and/or for memory deficits disclosed by the DGD condition during the semantic decision task investigated in the present study., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

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 © 2011 Elsevier Ltd. All rights reserved.)

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 © 2011 Elsevier Ltd. All rights reserved.)

The aim of our paper is to show that there is a sense of body that is enactive in nature and that enables to capture the most primitive sense of self. We will argue that the body is primarily given to us as source or power for action, i.e., as the variety of motor potentialities that define the horizon of the world in which we live, by populating it with things at hand to which we can be directed and with other bodies we can interact with. We will show that this sense of body as bodily self is, on the one hand, antecedent the distinction between sense of agency and sense of ownership, and, on the other, it enables and refines such distinction, providing a conceptual framework for the coherent interpretation of a variety of behavioral and neuropsychological data. We will conclude by positing that the basic experiences we entertain of our selves as bodily selves are from the very beginning driven by our interactions with other bodies as they are underpinned by the mirror mechanism., (2009 Elsevier Ltd. All rights reserved.)

Recent years have seen convergence in research on brain mechanisms and neurocomputational approaches, culminating in the creation of a new generation of robots whose artificial "brains" respect neuroscience principles and whose "cognitive" systems venture into higher cognitive domains such as planning and action sequencing, complex object and concept processing, and language. The present article gives an overview of selected projects in this general multidisciplinary field. The work reviewed centres on research funded by the EU in the context of the New and Emergent Science and Technology, NEST, funding scheme highlighting the topic "What it means to be human". Examples of such projects include learning by imitation (Edici project), examining the origin of human rule-based reasoning (Far), studying the neural origins of language (Neurocom), exploring the evolutionary origins of the human mind (Pkb140404), researching into verbal and non-verbal communication (Refcom), using and interpreting signs (Sedsu), characterising human language by structural complexity (Chlasc), and representing abstract concepts (Abstract). Each of the communication-centred research projects revealed individual insights; however, there had been little overall analysis of results and hypotheses. In the Specific Support Action Nestcom, we proposed to analyse some NEST projects focusing on the central question "What it means to communicate" and to review, understand and integrate the results of previous communication-related research, in order to develop and communicate multimodal experimental hypotheses for investigation by future projects. The present special issue includes a range of papers on the interplay between neuroinformatics, brain science and robotics in the general area of higher cognitive functions and multimodal communication. These papers extend talks given at the NESTCOM workshops, at ICANN (http://www.his.sunderland.ac.uk/nestcom/workshop/icann.html) in Porto and at the first meeting of the Federation of the European Societies of Neuropsychology in Edinburgh in 2008 (http://www.his.sunderland.ac.uk/nestcom/workshop/esn.html). We hope that the collection will give a vivid insight into current trends in the field.

Transcranial magnetic stimulation (TMS) was used to investigate whether the excitability of the corticospinal system is selectively affected by motor imagery. To this purpose, we performed two experiments. In the first one we recorded motor evoked potentials from right hand and arm muscles during mental simulation of flexion/extension movements of both distal and proximal joints. In the second experiment we applied magnetic stimulation to the right and the left motor cortex of subjects while they were imagining opening or closing their right or their left hand. Motor evoked potentials (MEPs) were recorded from a hand muscle contralateral to the stimulated cortex. The results demonstrated that the excitability pattern during motor imagery dynamically mimics that occurring during movement execution. In addition, while magnetic stimulation of the left motor cortex revealed increased corticospinal excitability when subjects imagined ipsilateral as well as contralateral hand movements, the stimulation of the right motor cortex revealed a facilitatory effect induced by imagery of contralateral hand movements only. In conclusion, motor imagery is a high level process, which, however, manifests itself in the activation of those same cortical circuits that are normally involved in movement execution.

In this investigation we studied the influence of object velocity on the transport and on the grasp components of prehension movements directed to approaching objects. Three experiments were carried out. In the first experiment six subjects were required to reach and grasp a sphere that approached them with a constant velocity. The effects of four velocities were studied. The results showed that the end point of the arm movement changed with object velocity: nearer the body with higher than with lower object velocities. Transport velocity increased with movement amplitude and the deceleration phase decreased in duration with higher object velocities. On the contrary the grasp component was not affected by object velocity. The second experiment was a control experiment carried out in order to verify whether a possible influence of object velocity on the grasp could be revealed in an experimental condition in which grasp planning relies without doubt on visual computation of all object features. In this experiment object velocity and object size were randomly varied. The results showed that the grasp was not influenced by object velocity, whereas it was sensitive to changes of object size. The third experiment had the two-fold aim of establishing (1) whether transport velocity was influenced by object velocity once the location in space at which the object had to be grasped was fixed and (2) whether the grasp kinematics differed for prehension movements directed respectively to stationary or to moving objects. Results showed that the first part of the transport is affected only by distance, whereas the deceleration phase decreased with increasing object velocity. This last result suggests that subjects minimized object displacements in order to grasp the sphere correctly. The grasp component differed between the conditions of stationary and moving stimuli only in the relative timing between finger aperture and closure phases. The closure phase decreased in the condition of moving stimuli. The results of the three experiments indicate the dependence of transport parameters on object velocity, whereas grasp parameters appear to be unaffected.