Language in the Mismatch Negativity Design

摘要

The article considers neurophysiological and psycholinguistic motivations for applying mismatch negativity (MMN) to studying the language function, briefly reviews the current evidence in the field, and offers some further directions for research in this area. MMN, a well-known index of automatic acoustic change detection, has also been found to be a sensitive indicator of long-term memory traces for native language sounds (phonemes, syllables). When comparing MMNs to words and meaningless pseudowords, we found larger amplitudes for words than for meaningless items. This was interpreted as a neurophysiological signature of word-specific memory circuits/cell assemblies activated in the human brain in a largely automatic and attention-independent fashion. This lexical enhancement of the word-elicited MMN has now been replicated by different groups using different languages and methodologies. We have also demonstrated that, using MMN, it is possible to register differences in the brain response to individual words and even to different aspects of referential semantics, confirming that the cortical memory circuits of individual lexical items can be revealed by the MMN. In other studies, we found evidence that the mismatch negativity reflects automatic syntactic processing commencing as early as ~100 ms after relevant information becomes available in the acoustic input. More recently, MMN responses were found to be sensitive to semantic context integration processes. In summary, neurophysiological imaging of the MMN response provides a unique opportunity to see subtle spatio-temporal dynamics of the neural processes underlying the language function in the human cortex in lexical, semantic, and syntactic domains.