Figure 2.

Steady-state properties of passive electrical conduction. A, Right, Reconstruction of a piriform cortex (PC) pyramidal cell with the positions of somatic and dendritic (d _S-D = 450 μm from soma) recordings. Left, Two-port T-circuit corresponding to the recording setup. B, Top, Step current injections to the dendrite and resulting voltage response at dendrite (red) and soma (black). Bottom, Same as top but for injections at the soma. C, Measured steady-state voltage (circles) in soma and dendrite as a function of injected current, the slope of linear regressions (lines) gives input or transfer resistances. The transfer resistance is the same for both directions of current injection (reciprocity) showing the linearity of electrical conduction in the dendrites. D, Absolute value of input resistances at the dendrite (red) and soma (black) for all paired recording plotted as a function of the distance between the recording sites (i.e., each point is a different recording in a different cell). Filled symbols: pyramidal cells; empty symbols: semilunar cells. E, Ratio of dendritic and somatic input resistances. F, Ratio of transfer resistance and dendritic input resistance (i.e., fraction of transmitted voltage from dendrite to soma). G, Ratio of transfer resistance and somatic input resistance (i.e., fraction of transmitted current from dendrite to soma, or equivalently, fraction of transmitted voltage from soma to dendrite).