MEG—measured auditory steady-state oscillations show high test–retest reliability: A sensor and source-space analysis

Stability of oscillatory signatures across magnetoencephalography (MEG) measurements is an important prerequisite for basic and clinical research that has been insufficiently addressed. Here, we evaluated the test–retest reliability of auditory steady-state responses (ASSRs) over two MEG sessions. The study required participants (N=13) to detect the rare occurrence of pure tones interspersed within a stream of 5Hz or 40Hz amplitude-modulated (AM) tones. Intraclass correlations (ICC; Shrout and Fleiss, 1979) were derived to assess stability of spectral power changes and the inter-trial phase coherence (ITPC) of task-elicited neural responses. ASSRs source activity was estimated using eLORETA beamforming from bilateral auditory cortex. ASSRs to 40Hz AM stimuli evoked stronger power modulation and phase-locking than 5Hz stimulation. Overall, spectral power and ITPC values at both sensor- and source-level showed robust ICC values. Notably, ITPC measures yielded higher ICCs (~0.86–0.96) between sessions compared to the assessment of spectral power change (~0.61–0.82). Our data indicate that spectral modulations and phase consistency of ASSRs in MEG data are highly reproducible, providing support for MEG-measured oscillatory parameters in basic and clinical research. •Spectral and phase-locking measures of ASSR to 5Hz and 40Hz AM tones are reliable.•Relative to spectral measures of ASSR, intraclass correlations derived from ITPC are more robust.•Sensor- and source-derived ITPC measures of ASSR show comparably high reliability.