A Neocortical Delta Rhythm Facilitates Reciprocal Interlaminar Interactions via Nested Theta Rhythms

作者：Carracedo Lucy M; Kjeldsen Henrik; Cunnington Leonie; Jenkins Alastair; Schofield Ian; Cunningham Mark O; Davies Ceri H; Traub Roger D; Whittington Miles A^*

来源：Journal of Neuroscience, 2013, 33(26): 10750-10761.

DOI：10.1523/JNEUROSCI.0735-13.2013

Delta oscillations (1-4 Hz) associate with deep sleep and are implicated in memory consolidation and replay of cortical responses elicited during wake states. A potent local generator has been characterized in thalamus, and local generators in neocortex have been suggested. Here we demonstrate that isolated rat neocortex generates delta rhythms in conditions mimicking the neuromodulatory state during deep sleep (low cholinergic and dopaminergic tone). The rhythm originated in an NMDA receptor-driven network of intrinsic bursting (IB) neurons in layer 5, activating a source of GABA(B) receptor-mediated inhibition. In contrast, regular spiking (RS) neurons in layer 5 generated theta-frequency outputs. In layer 2/3 principal cells, outputs from IB cells associated with IPSPs, whereas those from layer 5RS neurons related to nested bursts of theta-frequency EPSPs. Both interlaminar spike and field correlations revealed a sequence of events whereby sparse spiking in layer 2/3 was partially reflected back from layer 5 on each delta period. We suggest that these reciprocal, interlaminar interactions may represent a %26quot;Helmholtz machine%26quot;-like process to control synaptic rescaling during deep sleep.

• 出版日期2013-6-26