Sarcopenia is the loss of skeletal muscle tone, mass and strength associated with aging and lack of exercise. Its incidence is increasing, due to the growth in the number and proportion of older persons in world's population. To prevent the onset of Sarcopenia and to contrast its effects, it is important to perform on a regular basis physical exercises involving the upper and lower limbs. One of the main problems is to motivate elderly people to start a training routine, even better if in groups. This determines the need of innovative, stimulating solutions, targeting groups of people and easily usable. The primary objective of this study was to develop and test a new method for answering this need. We designed a platform where the humanoid robot Pepper guided a group of subjects to perform a set of physical exercises specifically designed to contrast Sarcopenia. The robot illustrated, demonstrated, and then performed the exercises simultaneously with the subjects' group. Moreover, by using an additional external camera Pepper controlled in real time the execution of the exercises, encouraging Participants who slow down or did not complete all the movements. The processing offline of the recorded data allowed estimating individual subjects performance. The platform has been tested with 8 volunteers divided into two groups. The preliminary results were encouraging: participants demonstrated a high degree of satisfaction for the robot-guided training. Moreover, participants moved with almost synchronously, indicating that all of them followed the robot, maintaining engagement and respecting the correct timing of the exercises.

BACKGROUND: In the evaluation of Stereo-Electroencephalography (SEEG) signals, the physicist's workflow involves several operations, including determining the position of individual electrode contacts in terms of both relationship to grey or white matter and location in specific brain regions. These operations are (i) generally carried out manually by experts with limited computer support, (ii) hugely time consuming, and (iii) often inaccurate, incomplete, and prone to errors. RESULTS: In this paper we present SEEG Assistant, a set of tools integrated in a single 3DSlicer extension, which aims to assist neurosurgeons in the analysis of post-implant structural data and hence aid the neurophysiologist in the interpretation of SEEG data. SEEG Assistant consists of (i) a module to localize the electrode contact positions using imaging data from a thresholded post-implant CT, (ii) a module to determine the most probable cerebral location of the recorded activity, and (iii) a module to compute the Grey Matter Proximity Index, i.e. the distance of each contact from the cerebral cortex, in order to discriminate between white and grey matter location of contacts. Finally, exploiting 3DSlicer capabilities, SEEG Assistant offers a Graphical User Interface that simplifies the interaction between the user and the tools. SEEG Assistant has been tested on 40 patients segmenting 555 electrodes, and it has been used to identify the neuroanatomical loci and to compute the distance to the nearest cerebral cortex for 9626 contacts. We also performed manual segmentation and compared the results between the proposed tool and gold-standard clinical practice. As a result, the use of SEEG Assistant decreases the post implant processing time by more than 2 orders of magnitude, improves the quality of results and decreases, if not eliminates, errors in post implant processing. CONCLUSIONS: The SEEG Assistant Framework for the first time supports physicists by providing a set of open-source tools for post-implant processing of SEEG data. Furthermore, SEEG Assistant has been integrated into 3D Slicer, a software platform for the analysis and visualization of medical images, overcoming limitations of command-line tools.

In stereoscopic vision, the ability of perceiving the three-dimensional structure of the surrounding environment is subordinated to a precise and effective motor control for the binocular coordination of the eyes/cameras. If, on the one side, the binocular coordination of camera movements is a complicating factor, on the other side, a proper vergence control, acting on the binocular disparity, facilitates the binocular fusion and the subsequent stereoscopic perception process. In real-world situations, an effective vergence control requires further features other than real time capabilities: real robot systems are indeed characterized by mechanical and geometrical imprecision that affect the binocular vision, and the illumination conditions are changeable and unpredictable. Moreover, in order to allow an effective visual exploration of the peripersonal space, it is necessary to cope with different gaze directions and provide a large working space. The proposed control strategy resorts to a neuromimetic approach that provides a distributed representation of disparity information. The vergence posture is obtained by an open-loop and a closed-loop control, which directly interacts with saccadic control. Before saccade, the open-loop component is computed in correspondence of the saccade target region, to obtain a vergence correction to be applied simultaneously with the saccade. At fixation, the closed-loop component drives the binocular disparity to zero in a foveal region. The obtained vergence servos are able to actively drive both the horizontal and the vertical alignment of the optical axes on the object of interest, thus ensuring a correct vergence posture. Experimental tests were purposely designed to measure the performance of the control in the peripersonal space, and were performed on three different robot platforms. The results demonstrated that the proposed approach yields real-time and effective vergence camera movements on a visual stimulus in a wide working range, regardless of the illumination in the environment and the geometry of the system.

We show how a cortical model of early disparity detectors is able to autonomously learn effective control signals in order to drive the vergence eye movements of a binocular active vision system. The proposed approach employs early binocular mechanisms of vision and basic learning processes such as synaptic plasticity and reward modulation. The computational substrate consists of a population of modeled V1 complex cells, that provides a distributed representation of binocular disparity information. The population response also provides a global signal to describe the state of the system and thus its deviation from the desired vergence position. The proposed network, by taking into account the modification of its internal state as a consequence of the action performed, evolves following a differential Hebbian rule. Furthermore, the weights update is driven by an intrinsic signal derived by the overall activity of the population. Exploiting this signal implies a maximization of the population activity itself, thus providing an highly effective reward for the developing of a stable and accurate vergence behaviour. The efficacy of the proposed intrinsic reward signal is comparatively assessed against the ground-truth signal (the actual disparity) providing equivalent results, and thus validating the approach. Experimental tests in a simulated environment demonstrate that the proposed network is able to cope with vergent geometry and thus to learn effective vergence movements for static and moving visual targets in realistic situations.