Mechanical Factors in the Design of Chronic Recording Intracortical Microelectrodes

An engineering analysis is presented to estimate motions of the microelectrode tip with respect to the adjacent neural tissue in terms of the geometry and material properties of the electrode, its lead wire, and the cortex to gain understanding of a recently reported successful recording system.

Abstract

To obtain chronic recordings from single nerve cells in the cerebral cortex it is necessary to prevent motion of the microelectrode tip with respect to the adjacent neural tissue. This paper presents an engineering analysis to estimate these motions in terms of the geometry and material properties of the electrode, its lead wire, and the cortex. The results are used to gain an understanding of a recently reported successful recording system, and to thereby provide a design guide for future systems. In addition, a buckling analysis is presented for a class of microelectrodes to enable a minimum size to be achieved with an adequate safety margin.