The Jansen-Rit neural mass model describes the average activity of cortical columns, naturally generating the brain's 8–13 Hz alpha rhythm.
The Jansen-Rit model (1995) treats a cortical column as three interconnected neural populations: pyramidal cells, excitatory interneurons, and inhibitory interneurons. The sigmoid voltage-to-rate function introduces nonlinearity. With typical parameters, the model spontaneously oscillates at ~10 Hz — the brain's dominant resting-state alpha rhythm, visible in EEG.