Variable cerebral responses to equally distinct deviance in four auditory dimensions: A mismatch negativity study

In this study we compared the amplitude, latency, and spatial distribution of the mismatch negativity ~MMN!, elicited by tones deviating in either frequency, intensity, stimulus-onset asynchrony ~SOA! or location, and assessed inter- and intra-subject variability. Cross-dimensional comparisons were facilitated by adjusting the magnitude of deviance indi-vidually, so that the detection rates were similar, both across dimensions ~within subject! and across subjects ~within dimension!. Despite similar detection rates, the MMN elicited by frequency deviance was larger, and the MMN elicited by SOA deviance was earlier than the other types of MMN. The reliability of frequency-related MMN was better than that of the other types of MMN. The results highlight the problems of comparing MMN across dimensions, especially in clinical populations. Descriptors: Auditory discrimination, Event-related potentials, Mismatch negativity, Auditory attention, Clinical application Mismatch negativity ~MMN! is an event-related potential ~ERP! component elicited by a “deviant ” stimulus presented infrequently in a train of repeated “standard ” stimuli. Deviance may occur in different dimensions. For example, the deviant stimulus may differ from the standard in frequency ~e.g., Sams, Paavilainen, Alho, &amp