Propagation of Hippocampal Ripples to the Neocortex by Way of a Subiculum-Retrospleanial Pathway

Autor: Dietmar Schmitz, Silvia Oldani, Sam McKenzie, György Buzsáki, Daniel F. English, Prateep Beed, John J. Tukker, Noam Nitzan
Rok vydání: 2019
Předmět:
Zdroj: SSRN Electronic Journal.
ISSN: 1556-5068
DOI: 10.2139/ssrn.3381954
Popis: Bouts of high frequency activity known as sharp wave ripples (SPW-Rs) facilitate communication between the hippocampus and neocortex. However, the paths and mechanisms by which SPW-Rs broadcast their content are not well understood. Due to its anatomical positioning, the granular retrosplenial cortex (gRSC) may be a bridge for this hippocampo-cortical dialogue. Using silicon probe recordings in awake, head-fixed mice, we show the existence of SPW-R analogues in gRSC and investigate their coupling to hippocampal SPW-Rs. Ensemble activity across regions was congruent across ripples, as neurons in gRSC reliably distinguished the spike content of different types of SPW-Rs. We demonstrate that this coupling is brain-state-dependent, and delineate a topographically-organized anatomical pathway via VGlut2-expressing, bursty neurons in the subiculum. Optogenetic stimulation or inhibition of bursty subicular cells induced or reduced responses in superficial gRSC, respectively. These results identify a specific path and underlying mechanisms by which the hippocampus can convey neuronal content during SPW-Rs to the neocortex.
Databáze: OpenAIRE