Psychophysical studies have shown that temporal contingencies between acoustic and visual stimuli can induce plastic changes in temporal audiovisual processing. Here we study electrocorticogram (ECoG) synchronization in response to single auditory and visual stimuli before and after adaptation to contingent audiovisual stimulation, consisting of pure-tones and light-flashes presented asynchronously (200ms delay). We applied two modelling approaches based on the assumption that the different elementary frequency signals carry sub-information about the stimuli and that only some of these oscillators respond with increasing energy to stimulation. In the first model the effect of energy attenuation between oscillators is considered, whereas in the second all oscillators are supposed to be equal energy under normalization. We observe that the evoked response is dominated by frequencies in a 7-18Hz band (12,5Hz mean frequency) in the pre-adaptation phase. This is different from the evoked response in the post-adaptation phase which is dominated by oscillations in a 32-43Hz band (37,5Hz mean frequency). Moreover these evoked signals are rather generated by a phase reset of ongoing oscillations. Changes of signal energy in response to the stimulus without phase locking are found in the 60-100Hz band in the pre-, and in the 70-120Hz band in the post-adaptation phase.