Function and energy consumption constrain neuronal biophysics in a canonical computation: Coincidence detection
Fig 2
Quantifying MSO cell model performance and energy consumption.
(A) Voltage and membrane currents of minimal MSO model in response to 500 Hz pure tone sound wave. Synaptic conductances to the left, ipsilateral (blue) and right, contralateral (green) dendrite are phase-locked to the sound wave, which creates an ITD of 0.5 ms. Somatic (black curve) and axonal (orange) voltages and the total cell membrane currents fluctuate at 500 Hz in response to the synaptic input. Total sodium membrane currents (i.e., summed across entire cell) resulting from leak (dark blue) and synaptic input (light blue) as well as the total potassium currents resulting from IKLT (purple), leak (red) and synaptic input (orange) are shown. Model uses default parameters as defined in the Methods. (B) Firing rate of default cell model in response to a 5 s soundwave for a range of ITDs. Maximal firing rate at ITD = 0 ms (r0) and firing rate at ITD = 0.5 ms (r0.5) are marked. (C) Firing rate at ITD = 0 ms (r0, solid black curve) and ITD = 0.5 ms (r0.5, dashed curve) are shown when the synaptic peak conductance varies from 3 to 300 nS. Difference between the two curves (gray area in top panel, gray curve r0 − r0.5 in bottom panel) gives the rate modulation (“Rate mod.”) for the default model as a function of synapse strength. Maximal rate modulation is marked by open circles. (D) Time-averaged total cell membrane currents (summed over entire cell, see bottom panel in A), averaged for a 5 s pure tone sound wave stimulus with ITD = 0 ms.