Oscillations in the gamma-band frequency range have been described to be more closely connected to hemodynamic changes as assessed with functional magnetic resonance imaging (fMRI) than other aspects of neuronal activity. In addition, gamma-band oscillations have attracted much interest during the last few years since they are thought to play a crucial role in many aspects of brain function related to perception and cognition. It was the aim of the present simultaneous EEG-fMRI study to identify brain regions specifically involved in the generation of the auditory gamma-band response (GBR) using single-trial coupling of EEG and fMRI. Ten healthy subjects participated in this study. Three different runs of an auditory choice reaction task with increasing difficulty were performed. Brain activity was recorded simultaneously with high density EEG (61 channels) and fMRI (1.5 T). BOLD correlates of the GBR have been predicted using the single-trial amplitude of the GBR. Reaction times (p
