p075fig02.24 The membrane equations of neurophysiology describe how cell voltages change in response to excitatory, inhibitory, and passive input channels.  Each channel is described by a potential difference multiplied by a conductance.  With the special choices shown in the lower right-hand corner, this equation defines a feedforward shuntin on-center off-surround network.<BR>||  Membrane equations of neurophysiology.<BR>C*dp[dt] = (V(+) - V)*g(+) +(V(-) - V)*g(-) +(V(p) - V)*g(p)<BR>Shunting equation (not additive)<TABLE border="1"><TR><TD>V </td><TD>Voltage</td></tr><TR><TD>V(+), V(-), V(p) </td><TD>Saturating voltages</td></tr><TR><TD>g(+), g(-), g(p) </td><TD>Conductances</td></tr></table>V(+) = B, C = 1; V(-) = V(p) = 0;  g(+) = Ii; g(-) = sum[k≠i: Ik];<BR>lower V: V(+) = V(p) Silent inhibition, upper V: V(+). (Howell: see p068fig02.14 Grossberg's comment that Hodgkin&Huxley model was a <A HREF="images- Grossberg 2021/p068fig02.14 Hodgkin and Huxley: spike potentials in squid giant axon.png">"... Precursor of Shunting network model (Rail 1962) ..."</a>).