Theoretical Analysis of Pre-Receptor Image Conditioning in Weakly Electric Fish
Figure 5
The Effect of Skin Conductivity on Electric Image Generation
(A) Transcutaneous current density (electric image) of a metal cube (1cm3) placed at 0.5 mm from the skin, modelled on skin with different conductivities. Red: 10 μScm−2, cyan: 100 μScm−2 (similar to mormyromast epithelium), blue: 1,000 μScm−2, black: 10,000 μScm−2, magenta: 100,000 μScm−2. All these fish have an internal conductivity of 3,300 μScm−1. Dashed line shows the case of a fish with realistic internal conductivity and skin conductivity distribution.
(B) Transcutaneous voltage calculated from the transcutaneous current densities shown in (A), using the same colour code.
(C) Current peak (right axis, red trace) and voltage peak (left axis, blue trace) as a function of skin conductivity for fish with homogeneous skin.
(D) Normalized plot for (B), using same colour code. mel, mormyromast epithelium-like conductivity; rlh, realistic internal conductivity, heterogeneous skin distribution.