Electroencephalographic electrode montage in goats: topographical, radiological, and physiological assessment

The paucity of information on assortment of EEG leads in goats has hampered analysis of brain regional activity during different physiological, pathological, and ethological conditions in this species. Hence, the present study was designed to develop a montage with suitable combinations of EEG electrode arrays in goats. Ten specimens of freshly slaughtered goat heads (crossbreed of Jamunapari) were procured and preserved at -20 °C. Frozen samples were sliced sagittally and transversely to corroborate the link between intended topographic landmarks for EEG leads over the scalp and underlying provinces of the brain. Based on these observations, nine sites for EEG electrode placement were finalized so as to include the entire cerebral cortex. These electrode placement sites were further checked through another set of five goat heads. The electrode sites were then extrapolated to live animals for radiological (orthogonally) and physiological validation. The montage derived on basis on these electrode placement sites provided maximum brain coverage and they were found suitable for EEG in goats. Parietal and vertex areas of the brain were found to be most active during the resting phase with the right hemisphere exhibiting more activity than the left. The results indicated right hemisphere conservatism and an attentional process during the resting phase in goats.

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