Neural Interface Technologies for Monitoring and Manipulating Brain Activities

Euisik Yoon
University of Michigan
Dec. 1 09:10~09:40


In this talk, I will review the evolution of Michigan neural probe technologies toward scaling up the number of recording sites, enhancing the recording reliability, and integrating optical stimulation capability for optogenetic studies. We investigated scaling of probe geometry and the number of recording sites by reducing probe surface area and providing modular interface with signal processing circuits, while exploring polymer materials for providing flexibility in the shank body to reduce micromotion effects. For implementing optogenetic probes, we took two approaches. One is to monolithically integrate micro-LEDs to bring high-density optical stimulation sites close to the electrical recording site. The micro-LED is realized in a neural size (~10 microns) for monitoring signal propagation in complex local circuits of a densely-populated region of brain such as hippocampus. The other approach is to bring multiple wavelengths to the distal end of optical waveguides integrated on the probe shank, to allow excitation and inhibition of target neurons by switching the wavelength in the same target region of brain in a behaving animal. This also allows for independent multicolor excitation of pyramidal neurons (PYR) and interneurons (PV), which can elucidate synaptic connections between different cell types in a given local circuit.



  • 1990, University of Michigan, Ann Arbor ( Ph.D. – Electrical engineering)
  • 1984, Seoul National University (M.S. – Electronics engineering)
  • 1982, Seoul National University (B.S. – Electronics engineering)


Professional Career

  • 2008-Present, Professor, Department of Electrical Engineering and Computer Science at the University of Michigan, Ann Arbor, MI, Director, Solid-State Electronics Laboratory
  • 2005-2008, Professor, Department of Electrical and Computer Engineering at the University of Minnesota, Minneapolis, MN
  • 1996-2005, Professor, epartment of Electrical Engineering at Korea Advanced Institute of Science and Technology (KAIST) in Daejon, Korea
  • 1994-1996, Member, Technical Staff at Silicon Graphics Inc. in Mountain View, CA
  • 1990-1994, Fairchild Research Center of the National Semiconductor Corp. in Santa Clara, CA


Awards and Honors

  • 2003-2007, IEEE International Solid-State Circuit Conference program committee
  • 2005, general chair of International Symposium on Bio Micro & Nanosystems
  • 1999-2000, co-recipient of the Student Paper Award at the IEEE International Microwave Symposium