(A) Membrane potential fluctuation for three example cells in V1 of
behaving macaque in a fixation task. Top: membrane potential in single trials is
shown. Bottom: horizontal (magenta) and vertical (green) eye traces are shown.
The short horizontal bar indicates timescale.
(B) Input resistance measurements for these three example cells were
obtained by injecting negative current pulses. The duration of these current
pulses was 100 ms with a 150-ms interval (top). Bottom: eye traces are
shown.
(C) Estimation of input resistance by fitting changes in membrane
potential with a sum of two exponentials functions (see STAR Methods for details) for the three example cells.
Dashed lines represent double exponentials used to fit the data.
(D) A positive relationship between input resistance (Rn) and membrane
potential (Vm) for the three example cells. Each dot represents a current
injection pulse. Only injection pulses that fell within the 3-mV inclusion
criteria (see STAR Methods) were included
in the analysis. Red dashed lines represent linear regressions.
(E) Histograms of the Rn-Vm slopes for a population of cells from two
behaving macaques. The arrow indicates the median slope.
(F) Histograms of the Rn-Vm slopes for a population of V1 cells from
anesthetized mice.