whether it is perturbed by the stimulus, but neither time- nor phase-locked to it (induced activity). However, as the data presented above, and numerous other estimations of ITPC (e.g., Tallon-Baudry and Bertrand, 1999) illustrate, complete phase-locking across trials (i.e., ITPC = 1) is physiologically unrealistic. Therefore the boundary for defining whether stimulus-related activity should be considered to be evoked or induced is unclear. Rojas et al. (2008) point out that their data fit a model in which total (evoked + induced) stimulus-related γ-band power is equivalent in the participants with and without ASD, and that reduced inter-trial phase consistency, computationally, leads to a reduction of what is classed as evoked activity and an increase in what is classed as induced activity. Thus these authors conclude that the production of γ-band oscillations in response to external stimulation is no different in those with and without ASD, rather their data point toward dysfunction in the timing of γ-band oscillations in the participants with ASD.
