Is fast auditory change detection feature specific? An electrophysiological study in humans

Recent oddball studies showed that auditory change detection responses exist in the first 50 ms after sound onset, upstream of mismatch negativity (MMN). We examined if these early responses could be elicited by feature-specific changes, meaning changes in the value of one attribute of a stimulus, regardless of whether other attributes of the stimulus are changing or not. We used a multifeature paradigm with four types of deviants: frequency, duration, intensity, and interaural time difference. In the middle latency range, only frequency deviants led to an enhanced Nb response. All four feature changes generated significant MMNs. Our results indicate that human brain is capable of detecting a feature-specific change for frequency attributes in the middle latency. The different levels of information being encoded in two separate event-related potential time ranges support the notion of a hierarchical organization of auditory deviance detection.