Nonlinear Characteristics of Auditory Steady-State Responses in MEG

This report shows the first evidence that stochastic resonance can be triggered in the auditory steady state responses (ASSRs) in MEG (magnetoencephalogram) which was indicated either by increased synchrony to the stimulus or by increase in power of ASSR when there was certain amount of noise in addition to the sinusoidal AM sound compared with the ASSR when there was no noise. To obtain the above conclusion, we applied statistical analysis to each subject´s data rather than to the whole set of the data of all subjects because individual differences smoothed out the of noise addition when the data were averaged over all the subjects.