Reversal of theta rhythm flow through intact hippocampal circuits

Theta oscillations are thought to propagate unidirectionally along the hippocampal circuitry, from CA3 to CA1 and the subiculum. In this paper, Jackson and colleagues demonstrate that, in the intact rat hippocampus, theta activity can also flow in reverse from subiculum to CA3, and find that this phenomenon depends on long-range GABAergic inhibition.