Cyclic voltammetry and optical beam deflection (OBD) techniques in different electrolytes, KCl, KClO4, CsCl, NaCl, LiClO4, and LiCl, were used to study the ionic exchange processes in polypyrrole (PPy) doped with an anionic surfactant, dodecyl-benzenesulfonate (DBS-). Our results show the role played by the cations during the first redox process of the polymer. To compare the OBD curves in each electrolyte, they were normalized with respect to their dependence on the chemical nature of the electrolyte. The use of temporal convolution, proposed by Vieil et al. (J. Electroanal. Chem., 368 (1994) 183), to relate electrical current and angular optical beam deflection, allows the modeling of the OBD curves and the calculation of apparent diffusion coefficients for each electrolyte and the diffusion coefficient of each ionic species.7215964