Pyramidal–Interneuron Network Gamma (PING): excitatory cells fire → recruit inhibitory cells → suppress excitatory → cycle repeats at 30–80 Hz.
1.8
0.5
2.0
2.5
40
PING: E-cells receive external drive, fire first. They excite I-cells (fast AMPA synapses). I-cells fire and send GABA_A inhibition back to E-cells.
E-cells are suppressed, then recover, and the cycle repeats. Gamma frequency (γ ≈ 30–80 Hz) is set by GABA_A decay time (~10 ms).
ING (interneuron-only) gamma also shown when g_EI → 0 and I drive is large.