BC4 – Interfacing brain and body – Insights into opportunities, challenges and limitations from an engineering perspective

Lecturer: Thomas Stieglitz
Fields: Brain-Body Interface, Engineering, Society

Content

Neural engineering addresses the wet interface between electronic and biological circuits and systems. There is a need to establish stable and reliable functional interfaces to neuronal and muscular target structure in chronic application in neuroscientific experiments but especially in chronic applications in humans. Here, the focus will be laid on medical applications rather than on fictional scenarios towards eternal storage of the mind in the cloud. The physiological mechanisms as well as basic technical concepts will be introduced to lay a common knowledge for informed decisions and discussions. From a neural engineering point of view, proper selection of substrate, insulation and electrode materials is of utmost importance to bring the interface in close contact with the neural target structures, minimize foreign body reaction after implantation and maintain functionality over the complete implantation period. Different materials and associated manufacturing technologies will be introduced and assessed with respect to their strengths and weaknesses for different application scenarios. Different design and development aspects from the first idea to first-in-human studies are presented and challenges in translational research are discussed. Reliability data from long-term ageing studies and chronic experiments show the applicability of thin-film implants for stimulation and recording and ceramic packages for electronics protection. Examples of sensory feedback after amputation trauma, vagal nerve stimulation to treat hypertension and chronic recordings from the brain display opportunities and challenges of these miniaturized implants. System assembly and interfacing microsystems to robust cables and connectors still is a major challenge in translational research and transition of research results into medical products. Clinical translation raises questions and concerns when applications go beyond treatment of serious medical conditions or rehabilitation purposes towards life-style applications. The four sessions within this course “Interfacing brain and body” will cover (1) physiological and engineering aspects of technical interfaces to brain and body: fundamentals on optogenetics, recording of bioelectricity and electrical stimulation, (2) neuroscientific and clinical applications of neural technology like (3) the challenges of neural implant longevity and (4) ethical and societal considerations in neural technology use.

Literature

  • Cogan SF. Neural stimulation and recording electrodes. Annu Rev Biomed Eng. 10:275-309 (2008). DOI: 10.1146/annurev.bioeng.10.061807.160518
  • Hassler, C., Boretius, T., Stieglitz, T.: “Polymers for Neural Implants” J Polymer Science-Part B: Polymer Physics, 49 (1), 18-33 (2011). Erratum in: 49, 255 (2011); DOI: 10.1002/polb.22169
  • Alt, M.T., Fiedler, E., Rudmann, L., Ordonez, J.S., Ruther, P., Stieglitz, T. “Let there be Light – Optoprobes for Neural Implants”, Proceedings of the IEEE 105 (1), 101-138 (2017); DOI: 10.1109/JPROC.2016.2577518
  • Stieglitz, T.: Of man and mice: translational research in neuro¬technology, Neuron, 105(1), 12-15 (2020). DOI:10.1016/j.neuron.2019.11.030
  • Stieglitz, T.: Why Neurotechnologies ? About the Purposes, Opportunities and Limitations of Neurotechnologies in Clinical Applications. Neuroethics, 14: 5-16 (2021), doi: 10.1007/s12152-019-09406-7
  • Jacob T. Robinson, Eric Pohlmeyer, Malte Gather, Caleb Kemere, John E. Kitching, George G. Malliaras, Adam Marblestone, Kenneth L. Shepard, Thomas Stieglitz, Chong Xie. Developing Next-Generation Brain Sensing Technologies—A Review. IEEE Sensors Journal, 18(22), pp. 10163-10175 (2019) DOI: 10.1109/JSEN.2019.2931159
  • Boehler, C., Carli, S., Fadiga, L., Stieglitz, T., Asplund, M.: Tutorial: Guidelines for standardized performance tests for electrodes intended for neural interfaces and bioelectronics. Nature Protocols, 15 (11), 3557-3578 (2020) https://doi.org/10.1038/s41596-020-0389-2
  • Hofmann UG, Stieglitz T. Why some BCI should still be called BMI. Nat Commun. 2024 Jul 23;15(1):6207. doi: 10.1038/s41467-024-50603-7

Lecturer

Thomas Stieglitz was born in Goslar in 1965. He received a Diploma degree in electrical Engineering from Technische Hochschule Karlsruhe, Germany, in 1993, and a PhD and habilitation degree in 1998 and 2002 from the University of Saarland, Germany, respectively. In 1993, he joined the Fraunhofer Institute for Biomedical Engineering in St. Ingbert, Germany, where he established the Neural Prosthetics Group. Since 2004, he is a full professor for Biomedical Microtechnology at the Albert-Ludwig-University Freiburg, Germany, in the Department of Microsystems Engineering (IMTEK) at the Faculty of Engineering and currently serves the IMTEK as managing director, is deputy spokesperson of the Cluster BrainLinks-BrainTools, board member of the Intelligent Machine Brain Interfacing Technology (IMBIT) Center and spokesperson of the research profile “Signals for Life” of the university. He is further serving the university as member of the senate and as co-spokesperson of the commission for responsibility in research as well as the university medical center as advisory board member. He was awarded IEEE Fellow in 2022. Dr. Stieglitz is co-author of about 200 scientific journal and about 350 conference proceedings presentations and co-inventor of about 30 patents. He is co-founder and scientific advisory board member of the neurotech spin offs CorTec an neuroloop. His research interests include neural interfaces and implants, biocompatible assembling and packaging and brain machine interfaces.

Affiliation: University of Freiburg
Homepage: https://www.imtek.de/professuren/bmt