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To foster performance across all levels of sports practice, physical training has been integrated with various mental training practices. Recently, an integrative approach to neurocognitive enhancement tried to combine the strengths of mental practices (i.e. mindfulness) and of training with neurofeedback devices. Based on previous validation studies showing the effect of a combined mindfulness–neurofeedback program on neurocognitive efficiency and stress/anxiety levels, we aimed at testing the feasibility and potential of that intensive combined program for improving psychological well-being and attention regulation in sport contexts. 50 participants (sportspeople and volunteers not regularly involved in sports) were divided into groups undergoing experimental and active control training programs. The experimental one was based on breathing-awareness practices supported by a wearable neurofeedback, while the active control one included only breathing practices. Before and after training participants underwent standardized neuropsychological and electrophysiological assessment. Data analysis highlighted a significant reduction of response times and false alarms at computerized cognitive tasks in sportspeople who completed the training, as well as a consistent improvement of the N2 event-related potential — a marker of attention regulation processes. We have also observed a general reduction of perceived stress and increased ability to keep a non-evaluative stance. Findings extend available observations on cognitive and neural effects of combined mindfulness–neurofeedback practice by showing that it is possible to observe training effects even after a limited period of practice among sportspeople. Such early training effects might mirror optimized implicit learning curves due to peculiar sensitivity to bodily signals and awareness. • Physical and mental training could be integrated to foster performance in sports practice. • Based on previous studies, we tested an intensive combined mindfulness–neurofeedback neurocognitive enhancement program. • Sportspeople and volunteers not regularly involved in sports underwent experimental and active control training programs. • Sportspeople who completed the training showed improved behavioral and physiological markers of neurocognitive efficiency. • We observed early training effects among sportspeople, which might mirror optimized implicit learning curves. [ABSTRACT FROM AUTHOR]

Highlights • Behavioral responses of DoC patients to external stimuli are difficult to qualify. • Physiological correlates of touch/pain detection in DoC patients are still debated. • We observed increased frontal-parietal and ANS activation to touch and pain. • Noxious stimulation seemed to induce a more consistent pattern of covert responses. Abstract Since behavioral responses to external stimuli of patients presenting disorders of consciousness (DoC) are often difficult to qualify, covert physiological correlates of responsivity are deemed as potentially valuable tools to help assessment procedures. While noxious stimuli seem good candidates to explore DoC patients' responsivity, autonomic and electrophysiological correlates of pain detection in DoC patients are still debated. This research aims at investigating autonomic and cortical activation as covert measure of residual somatosensory and nociceptive processes in patients in vegetative state. Twenty-one patients received touch- and pain-related stimulations while autonomic and cortical measures were recorded, with minimal stress for them. Results showed an increased frontal and parietal activation in response to both touch and pain stimuli. Pain-related stimulation was however associated with greater delta parietal response, lower left frontal activation, and increased electrodermal and heart rate measures. Present findings suggest that both somatic stimulations could induce measurable central responses, which might mirror basic attention orientation and perceptual processes. Nonetheless, the nociceptive stimulation in particular seemed to induce a more consistent and informative pattern of covert response even if we used a mild pain-induction procedure. [ABSTRACT FROM AUTHOR]

Action observation is known to enhance sensorimotor system activation, and such effect has been linked to neural priming and response facilitation mechanisms. This facilitation effect, however, has been primarily studied by focusing on high-level motor proficiency, whereas evidence on the effect of observing poorly performed actions is still lacking. We then devised a study to investigate neural correlates of the observation of suboptimal motor acts as mirrored by corticospinal activation (via transcranial magnetic stimulation (TMS), Experiment 1) and by modulation of cortical oscillatory activity (via electroencephalography (EEG), Experiment 2). 40 participants were presented with four randomly reiterated videos. Videos depicted a healthy confederate, a minimally impaired multiple sclerosis (MS) patient, a mildly impaired MS patient, or a confederate trying to simulate mild motor difficulties performing a test concerning fine motor abilities. In Experiment 1 we analyzed TMS-induced motor-evoked potentials during the observation of videos. In Experiment 2 EEG data were analyzed in the frequency-domain. Analyses highlighted both increased corticospinal excitability and desynchronized alpha-beta oscillations during the observation of poorly performed motor acts performed by the mildly impaired MS patient. Further, we observed gradually increasing beta activity across videos reiterations, specifically for the minimally impaired patient’s video. Reported findings corroborate the hypotheses that the action-observation network and the motor system might be involved in processes evoked in the attempt to understand and predict observed actions which do not belong to the onlookers’ motor repertoire, reflecting in an increased sensorimotor activity. [ABSTRACT FROM AUTHOR]

Background The use of Acoustic Emission (AE) as a Structural Health Monitoring (SHM) technique is very attractive thanks to its ability to detect not only damage sources in real-time but also to locate them. Methods To demonstrate the AE capabilities on known damage modes, a carbon fibre panel was manufactured with cut fibres in a central location and subjected to fatigue loading to promote matrix cracking. Subsequently, a delamination was created within the panel using an impact load, and the test was continued. Results AE signals were located within the crack area in the first part of the test. After impact, AE signals were detected from both areas under fatigue loading; signals from this area were located and used for further analysis with the neural network technique. Conclusions The application of an unsupervised neural network based classification technique successfully separated two damage mechanisms, related to matrix cracking and delamination. The results obtained allowed a more detailed understanding of such sources of AE in carbon fibre laminates. [ABSTRACT FROM AUTHOR]

Abstract: Acoustic Emission (AE) is a promising technique for the damage detection and the real-time structural monitoring of composite lightweight structures; however data interpretation and discrimination among failure modes from AE data is difficult to be carried out without proper data processing techniques. In this paper, a neural-network based classification of AE signals from tensile tests of pultruded glass-fiber specimens is proposed. A self-organizing map is trained with AE data from one specimen; then the map is clustered with the k-means algorithm. The optimal number of clusters is chosen by a voting procedure that takes into account a number of quality indexes; then the clustered neural network is used to classify AE data from other specimen. Results have shown that the classifier built from a smooth specimen was able to correctly classify other specimens with the same and with a different material layup, and is capable of recognizing signals from notched specimens, thus providing interesting and encouraging indications in view of the application on real structures. [Copyright &y& Elsevier]

Abstract: Disruption of the sense of being effective and causally determinant in performing an action was explored in the present research by inducing an erroneous external spatial feedback in response to the subject''s behaviour. ERPs were recorded from fifteen subjects when they were receiving mismatching/matching feedback information on direction. In addition, subjective sensitivity to the external cues was monitored by Behavioural Inhibition System (BIS) and Behavioural Activation System (BAS) measures, as well as Behaviour Identification process was tested by Behavior Identification Form (BIF). One negative ERP deflections of higher amplitude was revealed in concomitance to false feedback, peaking at about 210ms post-stimulus, more central-posteriorly localized. We supposed that it may represent feedback-error system of which activity might be reflected in FRN, deputed to monitor the unattended feedback furnished by an external system. Moreover, a P3b effect was also observed in great measure for false spatial feedback, more posteriorly (Pz) distributed. According to the context-updating hypothesis, the P3b may reflect the revision of the mental model of the context. BIS showed to be more sensitive to both veridical and false feedback that increased FRN, whereas higher-BAS and BAS-Reward measures revealed an increased proactive attitude to external feedback (higher P3b). Finally, low-level of action representation explained FRN amplitude more than high-level one. [Copyright &y& Elsevier]

Reinforced Plastics spoke to Dr Davide Crivelli from the Politecnico di Milano about new methods for detecting damage in composites. [ABSTRACT FROM AUTHOR]

• Acoustic Emission for structural health monitoring of railway axles was studied. • Acoustic Emission detected damage before traditional non-destructive testing. • The nature of collected data was understood by an unsupervised classification. • An empirical relationship between suitable AE features and crack size was found. The in-service safety of railway axles is a very important engineering challenge, as it has a large impact not only from the economic point of view of the railway operator, but it has cascading effects on supply chains, loss of work productivity, and, in the most serious cases, loss of life. It is, therefore, vital that the structural integrity of such components is known, during their lifecycle, with the highest possible accuracy via precise modelling, reliable inspections and, more recently but still at research level, effective condition monitoring. With a focus on solid freight axles, the research investigates the applicability of Acoustic Emission as a structural health monitoring approach for determining the in-service condition of a full-scale axle. A fatigue crack propagation test is carried out in the lab subjecting the axle to many repetitions of a block load sequence defined from real service measurements. Acoustic Emission data are continuously recorded during the test, whilst crack size is periodically measured by conventional non-destructive techniques. Eventually, a first-approximation correlation is highlighted between Acoustic Emission data, post-processed by a machine-learning algorithm, and crack propagation ones. [ABSTRACT FROM AUTHOR]

Compromised social-perceptual ability has been proposed to contribute to social dysfunction in neurodevelopmental disorders. While such impairments have been identified in Williams syndrome (WS), little is known about emotion processing in auditory and multisensory contexts. Employing a multidimensional approach, individuals with WS and typical development (TD) were tested for emotion identification across fearful, happy, and angry multisensory and unisensory face and voice stimuli. Autonomic responses were monitored in response to unimodal emotion. The WS group was administered an inventory of social functioning. Behaviorally, individuals with WS relative to TD demonstrated impaired processing of unimodal vocalizations and emotionally incongruent audiovisual compounds, reflecting a generalized deficit in social-auditory processing in WS. The TD group outperformed their counterparts with WS in identifying negative (fearful and angry) emotion, with similar between-group performance with happy stimuli. Mirroring this pattern, electrodermal activity (EDA) responses to the emotional content of the stimuli indicated that whereas those with WS showed the highest arousal to happy, and lowest arousal to fearful stimuli, the TD participants demonstrated the contrasting pattern. In WS, more normal social functioning was related to higher autonomic arousal to facial expressions. Implications for underlying neural architecture and emotional functions are discussed. [ABSTRACT FROM AUTHOR]

Classifying the type of damage occurring within a structure using a structural health monitoring system can allow the end user to assess what kind of repairs, if any, that a component requires. This paper investigates the use of acoustic emission (AE) to locate and classify the type of damage occurring in a composite, carbon fibre panel during buckling. The damage was first located using a bespoke location algorithm developed at Cardiff University, called delta-T mapping. Signals identified as coming from the regions of damage were then analysed using three AE classification techniques; Artificial Neural Network (ANN) analysis, Unsupervised Waveform Clustering (UWC) and corrected Measured Amplitude Ratio (MAR). A comparison of results yielded by these techniques shows a strong agreement regarding the nature of the damage present in the panel, with the signals assigned to two different damage mechanisms, believed to be delamination and matrix cracking. Ultrasonic C-scan images and a digital image correlation (DIC) analysis of the buckled panel were used as validation. MAR’s ability to reveal the orientation of recorded signals greatly assisted the identification of the delamination region, however, ANN and UWC have the ability to group signals into several different classes, which would prove useful in instances where several damage mechanisms were generated. Combining each technique’s individual merits in a multi-technique analysis dramatically improved the reliability of the AE investigation and it is thought that this cross-correlation between techniques will also be the key to developing a reliable SHM system. [ABSTRACT FROM AUTHOR]

Abstract In industrial applications of composite materials, accurate characterisation of damage is vital. Acoustic Emission (AE) can be utilised to achieve this, however, in large-scale complex geometry components, traditional AE approaches have limitations. In this study a large carbon fibre specimen was used to generate different damage mechanisms under fatigue loading. The Delta T Mapping technique was used to locate damage and signal features were corrected using the Parameter Correction Technique (PCT). A comparison between results obtained using traditional signal features and those obtained using PCT is given. The results are validated using C-scanning and computed tomography. Matrix cracking and delamination were successfully identified using the PCT approach and improved location accuracy was achieved. [ABSTRACT FROM AUTHOR]