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bioRxiv · 10.64898/2026.07.16.738654

Measuring excitation/inhibition balance through field potentials

Rodriguez-Sanchez, J.·Diehl, G. W.·Cunningham, P. J.·Pinotsis, D.·Adams, R. A.·Redish, A. D.
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Abstract

Several electroencephalography-based metrics have been proposed to index excitation/inhibition balance (E/I). We used single-unit and local field potential recordings from rat medial prefrontal and orbitofrontal cortex and mouse visual cortex and hippocampus to evaluate four candidate metrics against empirically-measured E/I. While 1/f slope and gamma oscillations showed region and context dependencies, broadband (6-80 Hz) and high gamma (80-150 Hz) power consistently correlated with E/I, supporting their use as proxy measures. If at least 30 minutes' data from medial prefrontal cortex were used per animal, broadband power could rank the animals by their E/I ratio, suggesting it could be used as an individual differences measure.

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Rodriguez-Sanchez, J., Diehl, G. W., Cunningham, P. J., Pinotsis, D., Adams, R. A., Redish, A. D.. 2026-07-17. Measuring excitation/inhibition balance through field potentials. https://doi.org/10.64898/2026.07.16.738654

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