Progress in Superconductivity

The Korean Superconductivity Society (한국초전도학회)
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Development of a Magnetoencephalograph System for Small Animals

소동물용 뇌자도 측정 시스템 개발

  • Kim, J.E. (Brain and Cognition Measurement Laboratory, Korea Research Institute of Standards and Science(KRISS)) ;
  • Kim, I.S. (Brain and Cognition Measurement Laboratory, Korea Research Institute of Standards and Science(KRISS)) ;
  • Kang, C.S. (Brain and Cognition Measurement Laboratory, Korea Research Institute of Standards and Science(KRISS)) ;
  • Kwon, H. (Brain and Cognition Measurement Laboratory, Korea Research Institute of Standards and Science(KRISS)) ;
  • Kim, J.M. (Brain and Cognition Measurement Laboratory, Korea Research Institute of Standards and Science(KRISS)) ;
  • Lee, Y.H. (Brain and Cognition Measurement Laboratory, Korea Research Institute of Standards and Science(KRISS)) ;
  • Kim, K. (Brain and Cognition Measurement Laboratory, Korea Research Institute of Standards and Science(KRISS))
  • Received : 2011.07.02
  • Accepted : 2011.08.03
  • Published : 2011.08.31
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Abstract

We developed a four-channel first order gradiometer system to measure magnetoencephalogram for mice. We used double relaxation oscillation SQUID (DROS). The diameter of the pickup coil is 4 mm and the distance between the coils is 5 mm. Coil distance was designed to have good spatial resolution for a small mouse brain. We evaluated the current dipole localization confidence region for a mouse brain, using the spherical conductor model. The white noise of the measurement system was about 30 fT/$Hz^{1/2}$/cm when measured in a magnetically shielded room. We measured magnetic signal from a phantom having the same size of a mouse brain, which was filled with 0.9% saline solution. The results suggest that the developed system has a feasibility to study the functions of brain of small animals.

Keywords

References

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