The electrical conductivity of human cerebrospinal fluid at body temperature

The electrical conductivity of human cerebrospinal fluid (CSF) from seven patients was measured at both room temperature (25/spl deg/C) and body temperature (37/spl deg/C). Across the frequency range of 10 Hz-10 kHz, room temperature conductivity was 1.45 S/m, but body temperature conductivity was 1.79 S/m, approximately 23% higher. Modelers of electrical sources in the human brain have underestimated human CSF conductivity by as much as 44% for nearly two decades, and this should be corrected to increase the accuracy of source localization models.

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