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 individually, 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.