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Minas Salib, in the group led by Tim Viney and Peter Somogyi, has discovered a new type of neuronal pathway that may be important in memory. For the encoding and recall of episodic memories, nerve cells in the cerebral cortex are activated in precisely timed sequences. Rhythmicity facilitates the coordination of neuronal activity and these rhythms are detected as oscillations of different frequencies, such as 5–12 Hz theta oscillations. Degradation of these rhythms, such as through neurodegeneration, causes memory deficits. The medial septum, a part of the basal forebrain that innervates the hippocampal formation, contains neurons that fire with a high degree of rhythmicity (HRNs) and others that fire with a low degree of rhythmicity (LRNs). These distinct types of neuron may contribute differentially to the coordination of cortical neuronal activity. Minas and colleagues discovered that GABAergic LRNs preferentially innervate the dentate gyrus and the CA3 area of the hippocampus, regions important for episodic memory. These neurons act in parallel with the HRNs mostly via transient inhibition of inhibitory neurons. A figure from the paper describing these results was chosen to illustrate the front cover of the 5 June issue of Journal of Neuroscience.