Mismatch negativity-stimulation paradigms in past and in future

Predicting the unpredicted … brain response: A systematic review of the feature-related visual mismatch negativity (vMMN) and the experimental parameters that affect it

In this systematic review and meta-analysis, I consider aspects of experimental design that affect the visual mismatch negativity (vMMN)-an electrophysiological (neural) correlate of prediction error in vision that is typically largest between 150 ms and 300 ms in the event-related potential (ERP) at occipito-parietal regions on the scalp. I compiled data from 145 published studies investigating changes in a single property or feature of visual input. This review provides a concise summary of the vMMN literature on unexpected changes in features of visual input, outlining the most used (according to review) and optimal (following discussion on theoretical and practical implications) parameters of experiments investigating feature deviance for posterity as well as contemporary research. The data compiled was analysed to reveal meaningful relationships between aspects of experimental design and vMMN mean amplitude and peak latency. Results suggest that whether a control for adaptation is used, whether attention is towards vs. away from the stimulus of interest, and stimulus presentation time determines mean amplitude. Whether attention is towards vs. away from the stimulus of interest, the time between the stimulus of interest, deviant probability, and the number of standards separating deviants determines peak latency. There is also some indication that magnitude of deviance affects mean amplitude in studies exploring orientation deviance. This review and its findings elucidate potentially fruitful areas of future research.

Native language background affects the perception of duration and pitch

Estonian is a quantity language with both a primary duration cue and a secondary pitch cue, whereas Chinese is a tonal language with a dominant pitch use. Using a mismatch negativity experiment and a behavioral discrimination experiment, we investigated how native language background affects the perception of duration only, pitch only, and duration plus pitch information. Chinese participants perceived duration in Estonian as meaningless acoustic information due to a lack of phonological use of duration in their native language; however, they demonstrated a better pitch discrimination ability than Estonian participants. On the other hand, Estonian participants outperformed Chinese participants in perceiving the non-speech pure tones that resembled the Estonian quantity (i.e., containing both duration and pitch information). Our results indicate that native language background affects the perception of duration and pitch and that such an effect is not specific to processing speech sounds.

Markov chains as a proxy for the predictive memory representations underlying mismatch negativity

Events not conforming to a regularity inherent to a sequence of events elicit prediction error signals of the brain such as the Mismatch Negativity (MMN) and impair behavioral task performance. Events conforming to a regularity lead to attenuation of brain activity such as stimulus-specific adaptation (SSA) and behavioral benefits. Such findings are usually explained by theories stating that the information processing system predicts the forthcoming event of the sequence via detected sequential regularities. A mathematical model that is widely used to describe, to analyze and to generate event sequences are Markov chains: They contain a set of possible events and a set of probabilities for transitions between these events (transition matrix) that allow to predict the next event on the basis of the current event and the transition probabilities. The accuracy of such a prediction depends on the distribution of the transition probabilities. We argue that Markov chains also have useful applications when studying cognitive brain functions. The transition matrix can be regarded as a proxy for generative memory representations that the brain uses to predict the next event. We assume that detected regularities in a sequence of events correspond to (a subset of) the entries in the transition matrix. We apply this idea to the Mismatch Negativity (MMN) research and examine three types of MMN paradigms: classical oddball paradigms emphasizing sound probabilities, between-sound regularity paradigms manipulating transition probabilities between adjacent sounds, and action-sound coupling paradigms in which sounds are associated with actions and their intended effects. We show that the Markovian view on MMN yields theoretically relevant insights into the brain processes underlying MMN and stimulates experimental designs to study the brain's processing of event sequences.

The neuroscience of music – towards ecological validity

Studies in the neuroscience of music gained momentum in the 1990s as an integrated part of the well-controlled experimental research tradition. However, during the past two decades, these studies have moved toward more naturalistic, ecologically valid paradigms. Here, I introduce this move in three frameworks: (i) sound stimulation and empirical paradigms, (ii) study participants, and (iii) methods and contexts of data acquisition. I wish to provide a narrative historical overview of the development of the field and, in parallel, to stimulate innovative thinking to further advance the ecological validity of the studies without overlooking experimental rigor.