Robustness of neuronal tuning to binaural sound localization cues against age-related loss of inhibitory synaptic inputs
Fig 3
Simulated effects of inhibition loss on binaural tuning of LSO with amplitude compensation.
A. Schematic drawing of the LSO circuit with a loss of inhibitory synaptic inputs and potentiation of remaining inputs. Lost inputs are shown by dotted lines and potentiated inputs are indicated by thick lines. B. Simulated ILD-tuning curves for different numbers of inhibitory inputs. C. (Thin lines) peak (max) and trough (min) rates of the ILD-tuning curves. (Thick solid line) Modulation depth defined as the difference between maximum and minimum rates. D. Neuronal discriminability of ILD tuning curves averaged over the range between -45 and +15 dB and normalized to the value for 8 inhibitory inputs. E. Simulated envelope phase-tuning curves at 300 Hz for different numbers of inhibitory inputs. F. (Thin lines) peak (max) and trough (min) rates of the envelope phase-tuning curves. (Thick solid line) Modulation depth defined as the difference between maximum and minimum rates. G. Neuronal discriminability of envelope phase-tuning curves averaged over the range between -180 and +180 degrees and normalized to the value for 8 inhibitory inputs. In panels C, D, F, and G, simulated data for the uncompensated case (same curves as in the corresponding panels in Fig 2) are shown by gray dot-dashed lines for comparison; the filled circles show the response for the default number of inputs (Minh = 8).