Perception of visual stimuli improves with experience. For objects, learning is specific for the stimuli used during training. This is shown in perceptual learning paradigms in which visual perception is challenged by degrading the stimuli, e.g. by backward masking or adding simultaneous noise. We present the first study designed to investigate whether visual object learning is specific to the type of stimulus degradation used. Sixteen participants were trained to recognize common objects. Half of them was trained in a backward masking paradigm, the other half in a simultaneous noise addition paradigm. After five days, performance was measured in four tests: (1) the trained paradigm with the trained objects, (2) the trained paradigm with new objects, (3) the untrained paradigm with the trained objects and (4) the untrained paradigm with new objects. Training effects were specific for the trained objects. In addition, an object-specific transfer to the untrained paradigm was found. The group trained in the simultaneous noise addition paradigm showed a complete transfer of performance to the backward masking task. The transfer was only partial when reversed. This pattern of results indicates that both general processes and processes specific for the type of stimulus degradation are involved in perceptual learning.