a. Schematic of in vitro setup.
b. Average IPSCs (blue) and EPSCs (red) recorded in pyramidal cells during photo-stimulation of L6. Synaptic currents are averages of n = 5–12 cells. Inset, onset of EPSC.
c. Histogram of excitatory charge as a percentage of total charge.
d. Top traces: perforated patch recording from L5 pyramidal cell in response to depolarizing current injection with (right) and without (left) L6 photo-stimulation. Bottom graphs: spike rate with and without L6 photo-stimulation.
e. Average spike rate in control versus spike rate with L6 photo-stimulation for each cell.
f. Schematic of setup for focal photo-stimulation.
g. Top traces: spiking of L5 pyramidal cell to depolarizing current injection with focal photo-stimulation of L6 at three progressively more distant positions (left to right). Bottom graph: spike rate in control (black) and with focal photo-stimulation of L6 (blue) (n = 4). Delta indicates medial/lateral distance from radial axis through recording site.
h. Percentage of spike suppression plotted against horizontal displacement.