RT Journal Article
SR Electronic
T1 Evolution of Network Synchronization during Early Epileptogenesis Parallels Synaptic Circuit Alterations
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 9920
OP 9934
DO 10.1523/JNEUROSCI.4007-14.2015
VO 35
IS 27
A1 Kyle P. Lillis
A1 Zemin Wang
A1 Michelle Mail
A1 Grace Q. Zhao
A1 Yevgeny Berdichevsky
A1 Brian Bacskai
A1 Kevin J. Staley
YR 2015
UL http://www.jneurosci.org/content/35/27/9920.abstract
AB In secondary epilepsy, a seizure-prone neural network evolves during the latent period between brain injury and the onset of spontaneous seizures. The nature of the evolution is largely unknown, and even its completeness at the onset of seizures has recently been challenged by measures of gradually decreasing intervals between subsequent seizures. Sequential calcium imaging of neuronal activity, in the pyramidal cell layer of mouse hippocampal in vitro preparations, during early post-traumatic epileptogenesis demonstrated rapid increases in the fraction of neurons that participate in interictal activity. This was followed by more gradual increases in the rate at which individual neurons join each developing seizure, the pairwise correlation of neuronal activities as a function of the distance separating the pair, and network-wide measures of functional connectivity. These data support the continued evolution of synaptic connectivity in epileptic networks beyond the latent period: early seizures occur when recurrent excitatory pathways are largely polysynaptic, while ongoing synaptic remodeling after the onset of epilepsy enhances intranetwork connectivity as well as the onset and spread of seizure activity.