The FRAP model implemented to calculate effective diffusion coefficients is based on 1D diffusion along a line with a set, characteristic length. This length, outlined in A, is defined as the average perimeter of an outer hair cell, and is represented by L in B. The circle in A represents the bleach ROI, which has a diameter of ∼2.9 μm and corresponds to ℓ in B. The boundary conditions and variables used are shown in B.