PT - JOURNAL ARTICLE AU - Manor, Yair AU - Nadim, Farzan AU - Epstein, Steven AU - Ritt, Jason AU - Marder, Eve AU - Kopell, Nancy TI - Network Oscillations Generated by Balancing Graded Asymmetric Reciprocal Inhibition in Passive Neurons AID - 10.1523/JNEUROSCI.19-07-02765.1999 DP - 1999 Apr 01 TA - The Journal of Neuroscience PG - 2765--2779 VI - 19 IP - 7 4099 - http://www.jneurosci.org/content/19/7/2765.short 4100 - http://www.jneurosci.org/content/19/7/2765.full SO - J. Neurosci.1999 Apr 01; 19 AB - We describe a novel mechanism by which network oscillations can arise from reciprocal inhibitory connections between two entirely passive neurons. The model was inspired by the activation of the gastric mill rhythm in the crab stomatogastric ganglion by the modulatory commissural ganglion neuron 1 (MCN1), but it is studied here in general terms. One model neuron has a linear current–voltage (I–V) curve with a low (L) resting potential, and the second model neuron has a linear current–voltage curve with a high (H) resting potential. The inhibitory connections between them are graded. There is an extrinsic modulatory excitatory input to the L neuron, and the L neuron presynaptically inhibits the modulatory neuron. Activation of the extrinsic modulatory neuron elicits stable network oscillations in which the L and H neurons are active in alternation. The oscillations arise because the graded reciprocal synapses create the equivalent of a negative-slope conductance region in theI–V curves for the cells. Geometrical methods are used to analyze the properties of and the mechanism underlying these network oscillations.