title: SEP-induced activity and its thermographic cortical representation in a murine model.
abstract: This article is a methodical report on the generation of reproducible changes in brain activity in a murine model. Somatosensory evoked potentials (SEP) are used to generate synchronized cortical activity. After electrical stimulation of mice forelimbs, the potentials were recorded with a flexible thin-film polyimide electrode structure directly from the cortex. Every registration included a simultaneous recording from both hemispheres that repeated four times to reproduce and compare the results. The SEPs in the murine model were shown to generate a very stable signal. The latency of the second positive wave (P2 wave) ranged between 16 and 19 ms, and the N1-P2 amplitude ranged between 39 and 48 µV. In addition, the temperature distribution of the cortex was acquired using infrared thermography. Surface cortical temperature changed during electrical stimulation without a clear hemispheric correlation. These initial results could be a step toward a better understanding of the different synchronized cortical activities and basic methods of evaluation of various mathematical algorithms to detect them.
authors.affiliation: Department Medical Engineering and Neuroprosthetics, Fraunhofer Institut für Biomedizinische Technik, St. Ingbert, Germany. klaus.hoffmann@ibmt.fraunhofer.de
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Hoffmann
authors.forename: Roman
authors.initials: R
authors.lastname: Ruff
authors.forename: Matthias
authors.initials: M
authors.lastname: Kirsch
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001931:Brain Mapping / Q000295:instrumentation* / Q000379:methods; D003344:Cortical Synchronization / Q000502:physiology*; D004558:Electric Stimulation / Q000295:instrumentation / Q000379:methods; D004567:Electrodes, Implanted; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D023421:Models, Animal; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013003:Somatosensory Cortex / Q000502:physiology*; D013817:Thermography / Q000295:instrumentation* / Q000379:methods