= Solution
A <dynamic clamp> is a real-time feedback experiment. Measure the <membrane potential> through an electrode, numerically evolve chosen channel or synapse state variables, calculate the modeled current, and inject that current into the real neuron. A virtual synapse might use $I_{\rm syn}=g_{\rm syn}(t)(E_{\rm syn}-V(t))$; a voltage-dependent virtual channel also updates its gate probabilities from the measured voltage. Repeat at a rate fast relative to the dynamics being modeled. Unlike voltage clamp, this procedure does not hold the voltage at a command value.
Two uses are to add a controlled inhibitory conductance and measure its effect on firing or integration, and to couple two real neurons by artificial reciprocal inhibitory <synapses> to test the resulting network dynamics. Both artificial conductances and reciprocal inhibitory connections were demonstrated in the primary https://scholarworks.brandeis.edu/esploro/outputs/journalArticle/Dynamic-clamp-computer-generated-conductances-in-real/9923970781201921[Sharp–O'Neil–Abbott–Marder dynamic-clamp experiments]. Conductance magnitude, time course and reversal voltage can be varied without requiring the cell to express a new channel. Sampling delay, electrode error and the inability of a single injection site to reproduce all dendritic conductance locations are practical limitations.
Back to article page
