Seizure-like thalamocortical rhythms initiate in the deep layers of the cortex in a co-culture model

Brendan E.L. Adams, Mervyn Kyi, Christopher A. Reid, Damian E. Myers, Shenghong Xu, David A. Williams, Terence J. O'Brien

Research output: Contribution to journalArticleResearchpeer-review

6 Citations (Scopus)


The oscillatory rhythms underlying many physiological and pathological states, including absence seizures, require both the thalamus and cortices for full expression. A co-culture preparation combining cortical and thalamic explants provides a unique model for investigating how such oscillations initiate and spread. Here we investigated the dynamics of synchronized thalamocortical activity by simultaneous measurement of field-potential recordings and rapid imaging of Ca2+ transients by fluorescence methods. Spontaneous sustained hypersynchronized "seizure-like" oscillations required reciprocal cortico-thalamocortical connections. Isolated cortical explants can independently develop brief discharges, while thalamic explants alone were unable to do so. Rapid imaging of Ca2+ transients demonstrated deep-layer cortical initiation of oscillatory network activity in both connected and isolated explants. Further, cortical explants derived from a rat model of genetic absence epilepsy showed increased bursting duration consistent with an excitable cortex. We propose that thalamocortical oscillatory network activity initiates in deep layers of the cortex with reciprocal thalamic interconnections enabling sustained hyper-synchronization.

Original languageEnglish
Pages (from-to)203-209
Number of pages7
JournalExperimental Neurology
Issue number1
Publication statusPublished - Jan 2011
Externally publishedYes


  • Absence seizures
  • Co-culture
  • Epilepsy
  • Rapid Ca imaging
  • Thalamocortical network

Cite this