Figure 5.

ΔV(t), d(ΔV(t))/dt and MUA of the moving bar. The MUA was first averaged across all 16 leads of the laminar probe, and then averaged across all animals to give the mean MUA for each cortical location. The ΔV(t) and the d(ΔV(t)/dt at each electrode penetration site for each animal were similarly averaged to give the mean ΔV(t) and the mean d(ΔV(t))/dt. These values were then normalized in time to give the mean MUA rel(t), mean ΔV(t)rel(t) and mean d(ΔV(t))/dt rel(t), see also “Materials and Methods”. Again data from both upward and downwards movement conditions were pooled as in Figure 3. Shaded areas indicate the SEM. At the cortical point representing the CFOV, the d(ΔV(t))/dt rel(t) (the inward current in the S layers) follows the MUA rel(t) with a lag of a few ms up to 70 ms. At 540 μm the MUA rel(t) does not appear to drive the d(ΔV(t))/dt rel(t). At 980 μm the ΔV(t) rel(t) leads the MUA rel(t) by some 200 ms. Center (Start from periphery): same variables measured for the bar starting in the peripheral FOV at the retinotopic point of CFOV.