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Abstract: Many neurons in the monkey ventral premotor area F5 discharge selectively when the monkey grasps an object with a specific grip. Of these, the motor neurons are active only during grasping execution, whereas the visuomotor neurons also respond to object presentation. Here we assessed whether the activity of 90 task-related F5 neurons recorded from two macaque monkeys during the performance of a visually-guided grasping task can be used as input to pattern recognition algorithms aiming to decode different grips. The features exploited for the decoding were the mean firing rate and the mean interspike interval calculated over different time spans of the movement period (all neurons) or of the object presentation period (visuomotor neurons). A support vector machine (SVM) algorithm was applied to the neural activity recorded while the monkey grasped two sets of objects. The original set contained three objects that were grasped with different hand shapes, plus three others that were grasped with the same grip, whereas the six objects of the special set were grasped with six distinctive hand configurations. The algorithm predicted with accuracy greater than 95% all the distinct grips used to grasp the objects. The classification rate obtained using the first 25% of the movement period was 90%, whereas it was nearly perfect using the entire period. At least 16 neurons were needed for accurate performance, with a progressive increase in accuracy as more neurons were included. Classification errors revealed by confusion matrices were found to reflect similarities of hand grips used to grasp the objects. The use of visuomotor neurons'' responses to object presentation yielded grip classification accuracy similar to that obtained from actual grasping execution. We suggest that F5 grasping-related activity might be used by neural prostheses to tailor hand shape to the specific object to be grasped even before movement onset. [Copyright &y& Elsevier]

Abstract: 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. [Copyright &y& Elsevier]

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. • PPS measured with a multisensory task did not extend after tool-use observation. • Reduced PPS plasticity was found with the increment of schizotypal traits. • Results suggest dissociated mechanisms below the altered PPS size and plasticity. • This evidence reveals new insights about self-boundaries in schizotypal spectrum. [ABSTRACT FROM AUTHOR]