RT Journal Article
SR Electronic
T1 Multiple sources of fast traveling waves during human seizures: resolving a controversy
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP JN-RM-0338-22
DO 10.1523/JNEUROSCI.0338-22.2022
A1 Emily D. Schlafly
A1 François A. Marshall
A1 Edward M. Merricks
A1 Uri T. Eden
A1 Sydney S. Cash
A1 Catherine A. Schevon
A1 Mark A. Kramer
YR 2022
UL http://www.jneurosci.org/content/early/2022/07/27/JNEUROSCI.0338-22.2022.abstract
AB During human seizures organized waves of voltage activity rapidly sweep across the cortex. Two contradictory theories describe the source of these fast traveling waves: either a slowly advancing narrow region of multiunit activity (an ictal wavefront) or a fixed cortical location. Limited observations and different analyses prevent resolution of these incompatible theories. Here we address this disagreement by combining the methods and microelectrode array recordings (N=11 patients, 2 females, N=31 seizures) from previous human studies to analyze the traveling wave source. We find - inconsistent with both existing theories - a transient relationship between the ictal wavefront and traveling waves, and multiple stable directions of traveling waves in many seizures. Using a computational model that combines elements of both existing theories, we show that interactions between an ictal wavefront and fixed source reproduce the traveling wave dynamics observed in vivo. We conclude that combining both existing theories can generate the diversity of ictal traveling waves.Significance StatementThe source of voltage discharges that propagate across cortex during human seizures remains unknown. Two candidate theories exist, each proposing a different discharge source. Support for each theory consists of observations from a small number of human subject recordings, analyzed with separately developed methods. How the different, limited data and different analysis methods impact the evidence for each theory is unclear. To resolve these differences, we combine the unique, human microelectrode array recordings collected separately for each theory and analyze these combined data with a unified approach. We show that neither existing theory adequately describes the data. We then propose a new theory that unifies existing proposals and successfully reproduces the voltage discharge dynamics observed in vivo.