Function and energy consumption constrain neuronal biophysics in a canonical computation: Coincidence detection
Fig 3
Length of MSO cell dendrites impose a trade-off between performance and energy consumption.
(A) Performance (i.e., maximal rate modulation, see Fig 2C; black curve) and energy costs (blue curve) as a function of dendrite length. Stimulus is a 5 s pure tone stimulus of 500 Hz. Default dendrite length is indicated by vertical gray bar. (B) Somatic EPSP halfwidth (black curve) and dendritic saturation (red curve), defined as the peak dendritic voltage normalized by its absolute maximum amplitude (i.e., Erev−Vrest = 60 mV). (C) Simulation setup to obtain EPSP halfwidth and dendritic saturation. Voltage is measured in dendrite (red) and soma (black). All synaptic inputs are activated simultaneously with a strength that gives a 10 mV EPSP at the soma (dotted line). Amplitude of the local dendritic response (dash-dotted line) and halfwidth of the somatic EPSP (dashed line) are measured. (D) Somatic EPSP traces are shown for three levels of dendritic saturation (top) and the somatic EPSP halfwidth is shown for the full range of dendritic saturation (bottom). Simulations use the default model; different levels of saturation are achieved by varying synaptic strength, leaving all model parameters constant. (E) Probability distributions of somatic voltage during 5 s simulations with ITD = 0 ms and ITD = 0.5 ms for the default model with a dendritic length of 185 μm (top) or 360 μm (bottom).