Pattern formation is studied numerically in a three-variable reaction-diffusion model with onset of the oscillatory instability at a finite wavelength. Traveling and standing waves, asymmetric standing-traveling wave patterns, and target patterns are found. With increasing overcriticality or system length, basins of attraction of more symmetric patterns shrink, while less symmetric patterns become stable. Interaction of a defect with an impermeable boundary results in displacement of the defect. Fusion and splitting of defects are observed.