A wearable heart rate measurement device for children with autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by early impairment in social and communication domains and autonomic nervous system unbalance. This study evaluated heart rate (HR) as a possible indicator of stress response in children with ASD as compared to children with language disorder (LD). Twenty-four patients [mean age = 42.62 months; SD = 8.14 months,12 with ASD (10 M/2F) and 12 with LD (8 M/4F)] underwent clinical [Leiter International Performance Scale-Revised, Autism Diagnostic Observation Schedule, second edition (ADOS-2)] and physiological evaluation (HR monitoring) during five interactive activities, while wearing an HR measurement device. IQ (ASD:IQ = 103.33 ± 12.85 vs. LD:IQ = 111.00 ± 8.88, p = 0.103) and fluid reasoning on the Leiter-R Scale were within the normal range in all subjects. Increased HR during the third activity (ADOS-2 bubble play) significantly correlated with autistic symptoms (r = 0.415; p = 0.044), while correlations between ADOS-2 total score and HR during the first activity (ADOS-2 free play; r = 0.368; p = 0.077), second activity (Leiter-R figure ground subscale; r = 0.373, p = 0.073), and fifth activity (ADOS-2 anticipation of a routine with objects; r = 0.368; p = 0.076) did not quite reach statistical significance. Applying a linear regression model, we found that the ADOS-2 total score significantly influenced HR variations (p = 0.023). HR monitoring may provide a better understanding of the stress-provoking situations for children with ASD. Furthermore, it could help clinicians detect the impact of the stressful condition on the autistic core and adress treatment strategy

Robust and language-independent acoustic features in Parkinson's disease

Introduction: The analysis of vocal samples from patients with Parkinson's disease (PDP) can be relevant in supporting early diagnosis and disease monitoring. Intriguingly, speech analysis embeds several complexities influenced by speaker characteristics (e.g., gender and language) and recording conditions (e.g., professional microphones or smartphones, supervised, or non-supervised data collection). Moreover, the set of vocal tasks performed, such as sustained phonation, reading text, or monologue, strongly affects the speech dimension investigated, the feature extracted, and, as a consequence, the performance of the overall algorithm. Methods: We employed six datasets, including a cohort of 176 Healthy Control (HC) participants and 178 PDP from different nationalities (i.e., Italian, Spanish, Czech), recorded in variable scenarios through various devices (i.e., professional microphones and smartphones), and performing several speech exercises (i.e., vowel phonation, sentence repetition). Aiming to identify the effectiveness of different vocal tasks and the trustworthiness of features independent of external co-factors such as language, gender, and data collection modality, we performed several intra- and inter-corpora statistical analyses. In addition, we compared the performance of different feature selection and classification models to evaluate the most robust and performing pipeline. Results: According to our results, the combined use of sustained phonation and sentence repetition should be preferred over a single exercise. As for the set of features, the Mel Frequency Cepstral Coefficients demonstrated to be among the most effective parameters in discriminating between HC and PDP, also in the presence of heterogeneous languages and acquisition techniques. Conclusion: Even though preliminary, the results of this work can be exploited to define a speech protocol that can effectively capture vocal alterations while minimizing the effort required to the patient. Moreover, the statistical analysis identified a set of features minimally dependent on gender, language, and recording modalities. This discloses the feasibility of extensive cross-corpora tests to develop robust and reliable tools for disease monitoring and staging and PDP follow-up

Sample volume length and registration accuracy assessment in quality controls of PW Doppler diagnostic systems: a comparative study

In clinical diagnostics, Pulsed Wave (PW) Doppler is one of the most used spectral Doppler techniques since it provides quantitative information about the severity of several cardiac disorders. Therefore, routine quality control tests should be scheduled to check whether a proper level of performance is maintained over time. Despite continuous research in the field, performance evaluation of Doppler equipment is still an open issue. Therefore, the present study is focused on the comparative investigation based on a test parameter for the automatic analysis of faults in sample volume length and range gate registration accuracy. The Velocity Profile Discrepancy Index (VPDI) provides a quantitative estimation according to the agreement between the theoretical parabolic velocity profile and the measured one. The index was assessed through an automatic method that post-processes PW spectrogram images acquired at six sample volume depths with respect to the vessel radius of a Doppler reference device. Tests were repeated for three brand-new ultrasound diagnostic systems, equipped with convex and phased array probes, in two working conditions. From the analysis of the results, a lower discrepancy between the measured and the theoretical velocity profile was found for the convex array probes as well as a lower uncertainty contribution

A 10-17 DOF Sensory Gloves with Harvesting Capability for Smart Healthcare

We here present a 10-17 Degrees of Freedom (DoF) sensory gloves for Smart Healthcare implementing an energy harvesting architecture, aimed at enhancing the battery lasting when powering the electronics of the two different types of gloves, used to sense fingers movements. In particular, we realized a comparison in terms of measurement repeatability and reliability, as well as power consumption and battery lasting, between two sensory gloves implemented by means of different technologies. The first is a 3D printed glove with 10 DoF, featuring low-cost, low-effort fabrication and low-power consumption. The second is a classical Lycra® glove with 14 DoF suitable for a more detailed assessment of the hand postures, featuring a relatively higher cost and power consumption. An electronic circuitry was designed to gather and elaborate data from both types of sensory gloves, differing for number of inputs only. Both gloves are equipped with flex sensors and in addiction with the electronics (including a microcontroller and a transmitter) allow the control of hand virtual limbs or mechanical arts in surgical, military, space and civil applications.Six healthy subjects were involved in tests suitable to evaluate the performances of the proposed gloves in terms of repeatability, reproducibility and reliability. Particular effort was devoted to increase battery lasting for both glove-based systems, with the electronics relaying on Radio Frequency, Piezoelectric and Thermoelectric harvesters. The harvesting part was built and tested as a prototype discrete element board, that is interfaced with an external microcontroller and a radiofrequency transmitter board. Measurement results demonstrated a meaningful improvement in battery operation time up to 25%, considering different operating scenarios

Reactive postural responses to continuous yaw perturbations in healthy humans: the effect of aging

Maintaining balance stability while turning in a quasi-static stance and/or in dynamic motion requires proper recovery mechanisms to manage sudden center-of-mass displacement. Furthermore, falls during turning are among the main concerns of community-dwelling elderly population. This study investigates the effect of aging on reactive postural responses to continuous yaw perturbations on a cohort of 10 young adults (mean age 28 ± 3 years old) and 10 older adults (mean age 61 ± 4 years old). Subjects underwent external continuous yaw perturbations provided by the RotoBit1D platform. Different conditions of visual feedback (eyes opened and eyes closed) and perturbation intensity, i.e., sinusoidal rotations on the horizontal plane at different frequencies (0.2 Hz and 0.3 Hz), were applied. Kinematics of axial body segments was gathered using three inertial measurement units. In order to measure reactive postural responses, we measured body-absolute and joint absolute rotations, center-of-mass displacement, body sway, and inter-joint coordination. Older adults showed significant reduction in horizontal rotations of body segments and joints, as well as in center-of-mass displacement. Furthermore, older adults manifested a greater variability in reactive postural responses than younger adults. The abnormal reactive postural responses observed in older adults might contribute to the well-known age-related difficulty in dealing with balance control during turning

Quantifying age-related differences of ankle mechanical properties using a robotic device

A deep analysis of ankle mechanical properties is a fundamental step in the design of an exoskeleton, especially if it is to be suitable for both adults and children. This study aims at assessing age-related differences of ankle properties using pediAnklebot. To achieve this aim, we enrolled 16 young adults and 10 children in an experimental protocol that consisted of the evaluation of ankle mechanical impedance and kinematic performance. Ankle impedance was measured by imposing stochastic torque perturbations in dorsi-plantarflexion and inversion-eversion directions. Kinematic performance was assessed by asking participants to perform a goal-directed task. Magnitude and anisotropy of impedance were computed using a multiple-input multiple-output system. Kinematic performance was quantified by computing indices of accuracy, smoothness, and timing. Adults showed greater magnitude of ankle impedance in both directions and for all frequencies, while the anisotropy was higher in children. By analyzing kinematics, children performed movements with lower accuracy and higher smoothness, while no differences were found for the duration of the movement. In addition, adults showed a greater ability to stop the movement when hitting the target. These findings can be useful to a proper development of robotic devices, as well as for implementation of specific training programs

An Algorithm for Choosing the Optimal Number of Muscle Synergies during Walking

In motor control studies, the 90% thresholding of variance accounted for (VAF) is the classical way of selecting the number of muscle synergies expressed during a motor task. However, the adoption of an arbitrary cut-off has evident drawbacks. The aim of this work is to describe and validate an algorithm for choosing the optimal number of muscle synergies (ChoOSyn), which can overcome the limitations of VAF-based methods. The proposed algorithm is built considering the following principles: (1) muscle synergies should be highly consistent during the various motor task epochs (i.e., remaining stable in time), (2) muscle synergies should constitute a base with low intra-level similarity (i.e., to obtain information-rich synergies, avoiding redundancy). The algorithm performances were evaluated against traditional approaches (threshold-VAF at 90% and 95%, elbow-VAF and plateau-VAF), using both a simulated dataset and a real dataset of 20 subjects. The performance evaluation was carried out by analyzing muscle synergies extracted from surface electromyographic (sEMG) signals collected during walking tasks lasting 5 min. On the simulated dataset, ChoOSyn showed comparable performances compared to VAF-based methods, while, in the real dataset, it clearly outperformed the other methods, in terms of the fraction of correct classifications, mean error (ME), and root mean square error (RMSE). The proposed approach may be beneficial to standardize the selection of the number of muscle synergies between different research laboratories, independent of arbitrary thresholds

Thermography and rasterstereography as a combined infrared method to assess the posture of healthy individuals

The demand for noninvasive methods to assess postural defections is increasing because back alterations are more common among the healthy population. We propose a combined infrared method of rasterstereography and thermography to assess the back without harmful effects. This study aims to provide reference data on rasterstereography and thermography to evaluate the back of a healthy population and to further study the correlation between these two methods. This cross-sectional research involved 175 healthy individuals (85 males and 90 females) aged 22 to 35 years. There is a large Cohen’s d effect size in the cervical depth (males = 43.77 ± 10.96 mm vs. females = 34.29 ± 7.04 mm, d = 1.03), and in the lumbar lordosis angle (males = 37.69 ± 8.89° vs. females = 46.49 ± 8.25°, d = − 1.03). The back temperature was different for gender in the cervical area (males = 33.83 ± 0.63 °C vs. females = 34.26 ± 0.84 °C, d = − 0.58) and dorsal area (males = 33.13 ± 0.71 °C vs. females = 33.59 ± 0.97 °C, d = − 0.55). Furthermore, in the female group there was a moderate correlation of lumbar temperature with lumbar lordosis angle (r = − 0.50) and dorsal temperature with shoulders torsion (r = 0.43). Males showed a moderate correlation for vertebral surface rotation RMS with cervical (r = − 0.46), dorsal (r = − 0.60), and lumbar (r = − 0.50) areas and cervical temperature with shoulders obliquity (r = 0.58). These results highlight a possible correlation between rasterstereography and thermography, which may elucidate the underlying mechanics of spinal alterations and thermal muscle response. Our findings may represent reference data for other studies using noninvasive methods to assess postural alterations