A Review of

Frontiers in psychology, 2011

Understanding speech is based on neural representations of individual speech sounds. In humans, such representations are capable of supporting an automatic and memory-based mechanism for auditory change detection, as reflected by the mismatch negativity (MMN) of event-related potentials. There are also findings of neural representations of speech sounds in animals, but it is not known whether these representations can support the change detection mechanism analogous to that ...

Neuroscience Letters, 1999

The mismatch negativity (MMN), an event-related potential component of the EEG, is elicited by violations of auditory regularities In the present study, the stimulus blocks contained two types of standard tones, differing from each other in frequency and intensity. MMNs were recorded to three different types of deviant stimuli: (a) feature deviants, differing from standards in their perceived locus of origin; (b) conjunction deviants, having the frequency of one of the standards and the intensity of the other; (c) double deviants, differing from standards in both (a) and (b). The MMN to double deviants was similar to the sum of the MMNs to feature and conjunction deviants. This result indicates that changes in simple stimulus features and conjunction of features are processed independently by the automatic sound change detection system indexed by MMN.

International Journal of Psychophysiology, 2013

The Mismatch Negativity (MMN), a component of the event-related potential (ERP), is elicited by a deviant following a series of standard stimuli. The present study addressed the question whether two deviants occurring successively in one hierarchically organized auditory object would elicit separate MMN responses. An example of such an object is a VC syllable (vowel+consonant). In a passive oddball protocol, the syllables [ɔx] and [ɛ∫] were presented both as standards and deviants so that both phonemes, the vowel and the consonant, changed in the respective deviant. Two negative responses were found in the deviant-minus-standard difference waves. Due to the latencies these effects could not be interpreted as separate MMN responses to the phonemic changes. Instead, the first effect (108 ms) was taken as an N1 modulation whereas the second negativity (168 ms) was interpreted as an MMN mainly reflecting the change of the initial vowel. Furthermore, the present data were statistically compared with related results from Steinberg et al. (2010a, b) obtained partly from the same stimuli presented in oddball blocks with simple mono-phonemic deviances due to changing vowels. Higher MMN amplitudes were found for the syllable [ɛ∫] in the present data compared to those previous findings. Although this difference was only present for one of the stimulus syllables, it is discussed as a possible indicator of an anticipatory MMN enhancement due to the predictability of the second change in the deviant of the present experiment.

Biological Psychology

To process complex stimuli like language, our auditory system must tolerate large acoustic variance, like speaker variability, and still be sensitive enough to discriminate between phonemes and to detect complex sound relationships in, e.g., prosodic cues. Our study determined discrimination of speech sounds in input mimicking natural speech variability, and detection of deviations in regular pitch relationships (rule violations) between speech sounds. We investigated the automaticity and the influence of attention and explicit awareness on these changes by recording the neurophysiological mismatch negativity (MMN) and P3a as well as task performance from 21 adults. The results showed neural discrimination of phonemes and rule violations as indicated by MMN and P3a, regardless of whether the sounds were attended or not, even when participants could not explicitly describe the rule. While small sample size precluded statistical analysis of some outcomes, we still found preliminary associations between the MMN amplitudes, task performance, and emerging explicit awareness of the rule. Our results highlight the automaticity of processing complex aspects of speech as a basis for the emerging conscious perception and explicit awareness of speech properties. While MMN operates at the implicit processing level, P3a appears to work at the borderline of implicit and explicit.

Frontiers in Neuroscience, 2014

NeuroImage, 2014

Keywords: MEG Binaural beat Oddball paradigm ASSRs MMN Parietal lobe-left middle frontal gyrus

Psychophysiology, 2003

In the auditory oddball paradigm, the frequent occurrence of a sound (the ''standard'') forms the basis of deviance detection. The incoming sounds are compared with the cortical representation of the standard and those sounds that do not match it elicit the mismatch negativity (MMN) event-related brain potential. Here we address the issue of whether the relative probability of the sounds in a sequence was a critical factor influencing which sounds would be represented as standards in the deviant comparison process. One frequent (F1) and two infrequent (D1 and D2) sounds that differed only in duration were presented in a sequence. D1 occurred proportionally as frequently with respect to D2 as F1 occurred with respect to D1. If the proportional relationship of sounds were critical then D1 could serve as a ''standard'' to D2 and thus D2 should elicit two MMNs. However, D2 elicited MMN only with respect to F1. This result as well as those obtained in two control conditions suggests that ''standards'' are not established on the basis of relative probability; they emerge as a result of global characteristics, the longer-term context, of the sound sequence.

Neuroscience Letters, 1999

We recorded event-related brain potentials (ERPs) to two different infrequent deviant tones presented successively within the repetitive sequence of a standard tone. A separate mismatch negativity (MMN) component was elicited by each of the two deviants when the interval separating their onsets was 300 ms. However, only a single MMN component was elicited when the temporal separation between the onsets of the two deviants was 150 ms. Previous studies obtained similar results using two temporally separated deviations carried by a single sound. Taken together, these results support the notion of a general temporal integration mechanism in the formation of auditory events with ca. 200 ms long window.

NeuroReport, 2007

We examined phonetic and sensory processes in speech perception using mismatch negativity, an event-related potential component congruent with discrimination, but which occurs for unattended stimuli. Adult listeners (N¼16) heard a repeated standard (the syllable 'da') that was interrupted infrequently by a phonetically di¡erent 'deviant' syllable ('ba').The acoustic di¡erence between standard and deviant was manipulated to create both acoustically Strong and Weak deviant stimuli. Mismatch negativities in response to the Strong deviant were signi¢cantly greater than those for the Weak deviant, in spite of the fact that both represented stable instances of the phonetic category. The data suggest that the mismatch negativity component can be strongly in£uenced by sensory factors beyond what is predicted by overt categorization and discrimination judgments. NeuroReport 18:901^905

Neuroscience Letters, 2003

The auditory sensory-memory mechanisms in the human brain were investigated using the mismatch negativity (MMN) component of the event-related potential. MMNs were recorded to stimuli deviating from the repetitive standard stimuli simultaneously either in one or two features (frequency, intensity). If the processing of these two features is independent of each other, the MMN to the double deviant should equal the sum of the MMNs elicited by the corresponding single deviants. The double-deviant MMNs were found to be additive at the electrode sites below the Sylvian fissure but not at the frontal scalp areas. The results suggest that the temporal subcomponent of MMN is additive whereas the frontal is non-additive. The pattern of results was similar in ignore and attend conditions, suggesting that the components were not attentionally modulated.