Online Ph.D Defence by Jian Dong
Jian Dong will defend his PhD thesis: "On the use of Subdermal Electrical Stimulation for Restoration of Sensory Feedback"
04.06.2020 kl. 13.00 - 16.00
13.00 Opening by the Moderator
13.05 PhD lecture by Jian Dong
14.00 Questions and comments from the Committee
Questions and comments from the audience at the Moderator’s discretion
16.00 Conclusion of the session by the Moderator
Due to the current circumstances the Ph.D defence will take place online via Skype for Business. If you wish to attend, please send an email to Kristine Uldal Knudsen before 02. June 2020 at 12:00.
The Faculty Council has appointed the following adjudication committee to evaluate the thesis and the associated lecture:
Associate Professor Christian Antfolk
Associate Professor Antoni Ivorra Cano
Universitat Pompeu Fabra
Professor Johannes Jan Struijk
Associate Professor Strahinja Dosen
The use of invasive electrical stimulation such as peripheral nerve stimulation, spinal cord stimulation and direct brain stimulation has been explored for providing sensory feedback through implantable electrodes. Though, surgery is inevitable to place these electrodes. As a non-invasive peripheral nerve stimulation, surface electrical stimulation has been studied intensively, however, the stability (i.e. repeatability and variability) over time has not been systematically explored and yet the stability of subdermal stimulation (minimally invasive) which could significantly decrease the energy consumption, feel more pleasant, and implant for long-term application (less reposition error) compares to surface stimulation. In this thesis, we hypothesized that sensory feedback evoked by subdermal electrical stimulation may have better overtime stability (e.g. due to less reposition error) of psychophysical measurements and better performance in closed-loop control system compare to surface stimulation.
Four studies were conducted in order to test this hypothesis. Study I compared psychophysical properties between surface and subdermal stimulation under varying intensities and frequencies (20 Hz and 100 Hz). Studies II and III tested how stable the surface and subdermal electrodes could deliver electrical stimulation over time windows (eight hours and seven days) in healthy and amputee subjects. Study IV tested the performance of the surface and subdermal stimulation-induced sensory feedback in closed-loop control tests.
Results showed that subdermal stimulation is a viable approach to surface stimulation for providing sensory feedback to amputees since subdermal stimulation evoked overall similar overtime stability and similar performance in the closed-loop control when owning its advantages compare to surface stimulation. Furthermore, this work provided insight into the properties of sensory feedback for practical application and addressed the specific advantages of each stimulation modalities which can be used for future studies on sensory feedback design.
HST - Department of Health Science and Technology
Skype for Business
02.06.2020 kl. 12.00