Inkjet-printed fully customizable and low-cost electrodes matrix for gesture recognition.

The use of surface electromyography (sEMG) is rapidly spreading, from robotic prostheses and muscle computer interfaces to rehabilitation devices controlled by residual muscular activities. In this context, sEMG-based gesture recognition plays an enabling role in controlling prosthetics and devices in real-life settings. Our work aimed at developing a low-cost, print-and-play platform to acquire and analyse sEMG signals that can be arranged in a fully customized way, depending on the application and the users' needs. We produced 8-channel sEMG matrices to measure the muscular activity of the forearm using innovative nanoparticle-based inks to print the sensors embedded into each matrix using a commercial inkjet printer. Then, we acquired the multi-channel sEMG data from 12 participants while repeatedly performing twelve standard finger movements (six extensions and six flexions). Our results showed that inkjet printing-based sEMG signals ensured significant similarity values across repetitions in every participant, a large enough difference between movements (dissimilarity index above 0.2), and an overall classification accuracy of 93-95% for flexion and extension, respectively.

Human-Machine Interaction Assessment by Neurophysiological Measures: A Study on Professional Air Traffic Controllers.

This study aims at investigating the possibility to employ neurophysiological measures to assess the humanmachine interaction effectiveness. Such a measure can be used to compare new technologies or solutions, with the final purpose to enhance operator's experience and increase safety. In the present work, two different interaction modalities (Normal and Augmented) related to Air Traffic Management field have been compared, by involving 10 professional air traffic controllers in a control tower simulated environment. Experimental task consisted in locating aircrafts in different airspace positions by using the sense of hearing. In one modality (i.e. "Normal"), all the sound sources (aircrafts) had the same amplification factor. In the "Augmented" modality, the amplification factor of the sound sources located along the participant head sagittal axis was increased, while the intensity of sound sources located outside this axis decreased. In other words, when the user oriented his head toward the aircraft position, the related sound was amplified. Performance data, subjective questionnaires (i.e. NASA-TLX) and neurophysiological measures (i.e. EEG-based) related to the experienced workload have been collected. Results showed higher significant performance achieved by the users during the "Augmented" modality with respect to the "Normal" one, supported by a significant decreasing in experienced workload, evaluated by using EEG-based index. In addition, Performance and EEG-based workload index showed a significant negative correlation. On the contrary, subjective workload analysis did not show any significant trend. This result is a demonstration of the higher effectiveness of neurophysiological measures with respect to subjective ones for Human-Computer Interaction assessment.

The motor cost of telling lies: electrocortical signatures and personality foundations of spontaneous deception.

Although universal, lying is generally considered immoral behavior. Most neuroscience studies on lying sanction or instruct deceptive behaviors and thus might fail to acknowledge the significance of lie-related moral conflicts. By combining electroencephalogram (EEG) recordings with a novel paradigm in which participants decided freely whether to deceive another person, we have generated indices of the cognitive (reaction times and stimulus-locked event-related components) and moral (readiness potential and its correlations with deception-related personality traits) cost of spontaneous deception. Our data fail to support the consensus that deception is cognitively more demanding than truth telling, suggesting that spontaneous deception, as opposed to lying out of requirement, might not mandate additional cognitive workload. Interestingly, lying was associated with decreased motor readiness, an event-related potential (ERP) component that is linked to motor preparation of self-determined actions and modulated when we face moral dilemmas. Notably, this reduction was less extensive in manipulative participants and greater in those who cared highly about their impression management. Our study expands on previous findings on deception by associating a cortical marker of reduced preparation to act with individual differences in moral cognition.

Perceiving monetary loss as due to inequity reduces behavioral and cortical responses to pain.

Studies indicate that physical and social pain may share some mechanisms and neural correlates. Nothing is known, however, on whether the neural activity in the nociceptive system, as indexed by laser-evoked potentials (LEPs), is modified when suffering the consequences of a conspecific violating social norms. To explore this issue, we created an interaction scenario where participants could gain money by performing a time-estimation task. On each win-trial, another player connected online could arbitrarily decide to keep the participant's pay-off for him- or herself. Thus, participants knew that monetary loss could occur because of their own failure in performing the task or because of the inequitable behavior of another individual. Moreover, participants were asked to play for themselves or on behalf of a third party. In reality, the win/loss events were entirely decided by an ad hoc programmed computer. At the end of the interaction, participants reported if they believed the game-playing interaction was real. Results showed that the loss due to the opponent's inequitable behavior brought about a reduction both in pain intensity self-reports and in the amplitude of LEPs' components (i.e., N2, N2/P2, P2a, P2b). Importantly, both the behavioral and neurophysiological effects were found in the participants who believed their deserved payoff was stolen by their opponent. Furthermore, reduction of vertex components was present only when the inequitable behavior was directed toward the self. These results suggest that, far from being a private experience, pain perception might be modulated by the social saliency of interpersonal interactions.