Journal of Neurophysiology Published 1 August 1996 Vol. 76 no. 2, 867-883
Dynamic clamping is merely current injection triggered by presynaptic voltage. The amount of current is determined mainly by postsynaptic voltage. There is nothing magical.
In this paper, the authors studied how systematic alterations in intrinsic and synaptic parameters affected the network behavior by using their newly-developed "dynamic clamping" on a pair of the gastric mill motor neurons, GMs. They isolated GMs by blocking synaptic transmission with picrotoxin and created reciprocally inhibitory two-cell circuits by the dynamic clamp.
The author demonstrated in this system that there was no bursting without the hyperpolarization-activated inward current (IH). In the presence of additional IH, a variety of circuit dynamics, including stable half-center oscillatory activity, was produced. The increase in synaptic conductance increased the burst period, whereas the increase in IH conductance reduced it. Discussion went on about synaptic threshold, saying that changes in the synaptic threshold might play a large role in turning on and off bursting activity. However, these discussion are not so informative to others because nonspiking synapses are rarely seen other than crustaceans.
The authors often stated that they "depolarized" or "hyperpolarized" the thoreshold for synapse. This is wrong. The threshold does not "polarize." Membrane potential does. They should have stated that the threshold was changed to more depolarized or hyperpolarized levels.
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