Raman study of flexure stressed poly(methyl methacrylate) (PMMA) plates at the frequency range of libration mode (80 cm(-1)), boson peak (14 cm(-1)), and quasi-elastic light scattering (QLS) (below 20 cm(-1)) is presented. The reversible changes in the vicinity of the Rayleigh line were attributed to partial disturbance of the midrange order due to stress-induced redistribution of random fluctuations of orientation.