Репозиторий Университета

© 2019 National Academy of Sciences. All rights reserved. Intracortical microstimulation (ICMS) of the primary somatosensory cortex (S1) can produce percepts that mimic somatic sensation and, thus, has potential as an approach to sensorize prosthetic limbs. However, it is not known whether ICMS could recreate active texture exploration—the ability to infer information about object texture by using one’s fingertips to scan a surface. Here, we show that ICMS of S1 can convey information about the spatial frequencies of invisible virtual gratings through a process of active tactile exploration. Two rhesus monkeys scanned pairs of visually identical screen objects with the fingertip of a hand avatar—controlled first via a joystick and later via a brain–machine interface—to find the object with denser virtual gratings. The gratings consisted of evenly spaced ridges that were signaled through individual ICMS pulses generated whenever the avatar’s fingertip crossed a ridge. The monkeys learned to interpret these ICMS patterns, evoked by the interplay of their voluntary movements and the virtual textures of each object, to perform a sensory discrimination task. Discrimination accuracy followed Weber’s law of just-noticeable differences (JND) across a range of grating densities; a finding that matches normal cutaneous sensation. Moreover, 1 monkey developed an active scanning strategy where avatar velocity was integrated with the ICMS pulses to interpret the texture information. We propose that this approach could equip upper-limb neuroprostheses with direct access to texture features acquired during active exploration of natural objects.

Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved. Objective: The article studies state-of-the art physical therapeutic techniques as a high degree of relevance to minimize invalidation and improve quality of life for patients with dental osteosarcoma. Materials and Methods: A randomized controlled clinical trial was conducted in 21 patients with osteogenic sarcoma of mandible (C41.1). There were 10 patients in the experimental group and 11 patients in the control group. Results: A comprehensive treatment and rehabilitation program for patients with osteosarcoma of mandible was developed. The first part of the program comprised 3 basic phases: preop chemotherapy, surgery, and postop rehabilitation. The surgical treatment further included resection of an affected part of the mandible and primary repair of the defect with jaw fragments and an autoimplant joined together with the help of positioning devices. The postop rehabilitation included postop chemotherapy and mesodiencephalic modulation (MDM). The second part of the program comprised preop examination, modeling, using stereolytic 3-dimensional models of the mandible, corrective surgeries, including implantation into the auto-implantda fragment of patient’s fibula, and building of a removable titanium alloy–based denture. MDM sessions were administered after each invasive intervention. Conclusions: Higher psychological and physical well-being was observed in the experimental group as compared with the control group (P, 0.01) in 2 weeks after the first surgery and 2 months after scheduled corrective surgeries, which finished in denture installation.