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Tactile attention tasks are used in the diagnosis and treatment of neurological and sensory processing disorders, while somatosensory event-related potentials (ERP) measured by electroencephalography (EEG) are used as neural correlates of attention processes. Brain-computer interface (BCI) technology provides an opportunity for the training of mental task execution via providing online feedback based on ERP measures. Our recent work introduced a novel electrotactile BCI for sensory training, based on somatosensory ERP; however, no previous studies have addressed specific somatosensory ERP morphological features as measures of sustained endogenous spatial tactile attention in the context of BCI control. Here we show the morphology of somatosensory ERP responses induced by a novel task introduced within our electrotactile BCI platform i.e., the sustained endogenous spatial electrotactile attention task. By applying pulsed electrical stimuli to the two proximal stimulation hotspots at the user’s forearm, stimulating sequentially the mixed branches of radial and median nerves with equal probability of stimuli occurrence, we successfully recorded somatosensory ERPs for both stimulation locations, in the attended and unattended conditions. Waveforms of somatosensory ERP responses for both mixed nerve branches showed similar morphology in line with previous reports on somatosensory ERP components obtained by stimulation of exclusively sensory nerves. Moreover, we found statistically significant increases in ERP amplitude on several components, at both stimulation hotspots, while sustained endogenous spatial electrotactile attention task is performed. Our results revealed the existence of general ERP windows of interest and signal features that can be used to detect sustained endogenous tactile attention and classify between spatial attention locations in 11 healthy subjects. The current results show that features of N140, P3a and P3b somatosensory ERP components are the most prominent global markers of sustained spatial electrotactile attention, over all subjects, within our novel electrotactile BCI task/paradigm, and this work proposes the features of those components as markers of sustained endogenous spatial tactile attention in online BCI control. Immediate implications of this work are the possible improvement of online BCI control within our novel electrotactile BCI system, while these finding can be used for other tactile BCI applications in the diagnosis and treatment of neurological disorders by employing mixed nerve somatosensory ERPs and sustained endogenous electrotactile attention task as control paradigms. Full article

Pulse palpation is an effective method for diagnosing arterial diseases. However, most pulse measurement devices use preconfigured pressures to collect pulse signals, and most pulse tactile simulators can only display standard or predefined pulse waveforms. Here, a portable interactive human pulse measurement and reproduction system was developed that allows users to take arbitrary pulses and experience realistic simulated pulse tactile feedback in real time by using their natural pulse-taking behaviors. The system includes a pulse tactile recorder and a pulse tactile player. Pulse palpation forces and vibrations can be recorded and realistically replayed for later tactile exploration and examination. To retain subtle but vital pulse information, empirical mode decomposition was used to decompose pulse waveforms into several intrinsic mode functions. Artificial neural networks were then trained based on intrinsic mode functions to determine the relationship between the driving signals of the pulse tactile player and the resulting vibration waveforms. Experimental results indicate that the average normalized root mean square error and the average R-squared values between the reproduced and original pulses were 0.0654 and 0.958 respectively, which indicate that the system can reproduce high-fidelity pulse tactile vibrations. Full article

Introduction: In the different branches of dentistry, the use of laser to solve different clinical situations is increasing due to numerous advantages that have been studied in literature since the 70s. Leucoplakia and hyperkeratosis can benefit from laser-assisted treatment. In most cases biopsy sampling, histological examination and, if no malignant cells are present, the follow-up is needed. However, even if the lesion is free of dysplasia patients often ask to eliminate these white spots that are always a cause of concern. Aim: From these numerous requests comes the idea of setting up a laser-assisted protocol as less invasive as possible to be offered to patients. The aim of the study is to find a laser-assisted protocol for the surgical excision of leucoplakia and hyperkeratosis that can both improve the clinical aspect of the lesion and be sustainable for patients. The null hypothesis has been identified in the following statement: the treatment is effective and efficient at the same time; where effectiveness was tested with the following criteria: size of the lesion, tactile perception, discomfort, pain; and efficiency with the following criteria: pain and discomfort perceived during the treatment. Materials and methods: To collect all data, a specially designed medical record was used. The diode laser was used with a pulsed mode and the maximum power corresponds to 1.8 W. No anaesthesia was used. Before laser-assisted treatment, the fibre was activated and was used with a contact overflowing. Results: Our results show a decrease in the size of the lesion statistically significant. No pain was referred during treatment, except for a slight burning sensation. Conclusion: In conclusion we can state that the treatment is both efficient and effective. Full article