Figure 7.

Model Analysis Identifies a Potential Mechanism Underlying the Amplification of Weak Basal Inputs based on Voltage-Dependent Currents

(A) Layer 2/3 pyramidal cell model; location of the simulated input is indicated by a cyan circle and arrow in the basal dendrites (orange); location of the simulated V_m recordings is indicated by two electrodes on the soma and on a basal dendrite close to the input stimulation; distal segments of the basal dendrites express a VGC (dark blue).

(B) Voltage response to input in basal dendrites (basal dendrite electrode in A) recorded at the location of the stimulus (top) and at the soma (bottom; see soma electrode in A). Responses are shown to weak (left) and strong (right) input in both V_dep (red curves) and V_hyp (blue traces). Black dotted line in top panels marks the half-activation voltage, V_h, of the current (see STAR Methods and Figure S6B). Dotted line in top panels marks the half-activation voltage of the current (see Figure S6B). Soma voltage change with respect to holding voltage (−60 mV for V_hyp or −50 mV for V_dep) is shown.

(C) Ratio of somatic amplitudes in V_dep versus V_hyp shown as a function of the V_dep amplitudes for basal input. Both model results (blue curve) and experimental data (open circles) are shown.