Superficial Slow Rhythms Integrate Cortical Processing in Humans

Milan Halgren, Daniel Fabó, István Ulbert, Joseph R. Madsen, Lorand Eross, Werner K. Doyle, Orrin Devinsky, Donald Schomer, Sydney S. Cash, Eric Halgren

Research output: Contribution to journalArticle

12 Citations (Scopus)


The neocortex is composed of six anatomically and physiologically specialized layers. It has been proposed that integration of activity across cortical areas is mediated anatomically by associative connections terminating in superficial layers, and physiologically by slow cortical rhythms. However, the means through which neocortical anatomy and physiology interact to coordinate neural activity remains obscure. Using laminar microelectrode arrays in 19 human participants, we found that most EEG activity is below 10-Hz (delta/theta) and generated by superficial cortical layers during both wakefulness and sleep. Cortical surface grid, grid-laminar, and dual-laminar recordings demonstrate that these slow rhythms are synchronous within upper layers across broad cortical areas. The phase of this superficial slow activity is reset by infrequent stimuli and coupled to the amplitude of faster oscillations and neuronal firing across all layers. These findings support a primary role of superficial slow rhythms in generating the EEG and integrating cortical activity.

Original languageEnglish
Article number2055
JournalScientific reports
Issue number1
Publication statusPublished - Dec 1 2018


ASJC Scopus subject areas

  • General

Cite this

Halgren, M., Fabó, D., Ulbert, I., Madsen, J. R., Eross, L., Doyle, W. K., Devinsky, O., Schomer, D., Cash, S. S., & Halgren, E. (2018). Superficial Slow Rhythms Integrate Cortical Processing in Humans. Scientific reports, 8(1), [2055].