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bioRxiv · 10.1101/2025.05.23.655841

Event-Related Spatio-Spectral Perturbation (ERSSP): A Scalp-Wide EEG Analysis Framework for Capturing Extralemniscal Thalamocortical Activity, Validated Using a Fragile X Syndrome Model

Kim, H.·Ethridge, L.·DeStefano, L.·Schmitt, L.·Pedapati, E.·Erickson, C.·Miyakoshi, M.
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Abstract

The extralemniscal thalamocortical pathway regulates large-scale modulation of cortical states but remains inaccessible to traditional EEG analysis due to its diffuse, variable, and asynchronous nature. To address this, we introduce the Event-Related Spatio-Spectral Perturbation (ERSSP) framework, which quantifies spatially distributed time-frequency responses. ERSSP summarizes the number of channels exhibiting significant spectral perturbations, capturing diffuse cortical dynamics from sensor-space EEG. We validated this approach using a passive auditory habituation task in individuals with Fragile X Syndrome (FXS), a condition marked by disrupted thalamocortical modulation. ERSSP revealed enhanced spatial extent of power increases (but not phase-locking) in FXS compared to controls. Results also showed expected gender differences, further supporting biological sensitivity of ERSSP. ERSSP provides a conceptually simple and computationally efficient method for quantifying broadly distributed sensory modulation and may enable new insights into thalamocortical function in both basic and clinical neuroscience.

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Kim, H., Ethridge, L., DeStefano, L., Schmitt, L., Pedapati, E., Erickson, C., Miyakoshi, M.. 2025-05-28. Event-Related Spatio-Spectral Perturbation (ERSSP): A Scalp-Wide EEG Analysis Framework for Capturing Extralemniscal Thalamocortical Activity, Validated Using a Fragile X Syndrome Model. https://doi.org/10.1101/2025.05.23.655841

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