Objective: The aim was to study how the measurement error affects the repeatability of mismatch negativity (MMN) measurements.
Methods: Event-related potentials (ERPs) to changes in sound frequency, location, intensity, duration, and composition were recorded five times during 1-3 weeks from 13 healthy adults using a multi-feature MMN paradigm. The accumulation of MMN was modeled empirically with respect to measurement error, and repeatability was estimated at 0.6-3.5-μV error levels. The analysis was made for the results in the single deviant conditions and their pattern (auditory discrimination profile).
Results: At the single-subject level, the measurement error significantly affected the repeatability until it went below 9-17% of MMN peak amplitude. At the group level, the threshold was higher. Peak amplitude was generally the most repeatable parameter. Latency was superior when the error was moderate or small (<2-3 μV).
Conclusions: The measurement error affects the repeatability of MMN. In single-subject studies, it should not be neglected if it exceeds 10% of the MMN amplitude. The application of the auditory discrimination profile is recommended for future applications.
Significance: The study provided quantitative results to support the discussion on improving the repeatability of the MMN measurements. They are expected to apply conditionally to other ERP measurements, too.
Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.