Four-Gaussian fits (line) to the $\dedx$ spectra (markers) for tracks having momentum in the range 3.4-3.6 $\gevc$ (upper figure) and 8.0-9.0 $\gevc$ (lower figure) with $|\eta|< 0.2$. In each panel, the signals of pions (rightmost Gaussian), kaons, and protons (leftmost Gaussian) are shown as red, green, and blue dashed areas, respectively. The contribution of electrons is small ($< 1\%$) and therefore not visible in the figure. Results for all six $\pbpb$ centrality classes are presented. The $\dedx$ spectra have all been normalized to have unit integrals.