Figure 1
The representative phase-locked (a) and non-phase-locked (b) responses in 46-Hz AM-FM ASSR in the ERA system. (a) and (b) are cases of a healthy participant and a patient with schizophrenia, respectively. Each vector in the diagram, which was created by each trial during the auditory stimulus, represents the phase and the amplitude of EEG activity corresponding to the tone modulation frequency rate. The phase angle of the vectors corresponds to the time delay between the presentation of the stimulus and the neural response of trials. The cross-trial phase consistency of the vectors determines the phase-locked or non-phase-locked response. While all trials are aligned in the same range in (a), the nonaligned trials that prevent the identification of phase-locked response are seen in (b). The mean length of the vectors represents the response amplitude (root mean square voltage, in microvolts) of the ASSR.
