Language in the Mismatch Negativity Design

2007 ◽  
Vol 21 (3-4) ◽  
pp. 176-187 ◽  
Author(s):  
Yury Shtyrov ◽  
Friedemann Pulvermüller

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.

2021 ◽  
Vol 15 ◽  
Author(s):  
Diego Mac-Auliffe ◽  
Benoit Chatard ◽  
Mathilde Petton ◽  
Anne-Claire Croizé ◽  
Florian Sipp ◽  
...  

Dual-tasking is extremely prominent nowadays, despite ample evidence that it comes with a performance cost: the Dual-Task (DT) cost. Neuroimaging studies have established that tasks are more likely to interfere if they rely on common brain regions, but the precise neural origin of the DT cost has proven elusive so far, mostly because fMRI does not record neural activity directly and cannot reveal the key effect of timing, and how the spatio-temporal neural dynamics of the tasks coincide. Recently, DT electrophysiological studies in monkeys have recorded neural populations shared by the two tasks with millisecond precision to provide a much finer understanding of the origin of the DT cost. We used a similar approach in humans, with intracranial EEG, to assess the neural origin of the DT cost in a particularly challenging naturalistic paradigm which required accurate motor responses to frequent visual stimuli (task T1) and the retrieval of information from long-term memory (task T2), as when answering passengers’ questions while driving. We found that T2 elicited neuroelectric interferences in the gamma-band (>40 Hz), in key regions of the T1 network including the Multiple Demand Network. They reproduced the effect of disruptive electrocortical stimulations to create a situation of dynamical incompatibility, which might explain the DT cost. Yet, participants were able to flexibly adapt their strategy to minimize interference, and most surprisingly, reduce the reliance of T1 on key regions of the executive control network-the anterior insula and the dorsal anterior cingulate cortex-with no performance decrement.


2013 ◽  
Vol 3 (6) ◽  
pp. 20130030 ◽  
Author(s):  
Minus van Baalen

Evolution can be characterized as a process that shapes and maintains information across generations. It is also widely acknowledged that information may play a pivotal role in many other ecological processes. Most of the ecologically relevant information (and some important evolutionary information too) is of a very subjective and analogue kind: individuals use cues that may carry information useful only to them but not to others. This is a problem because most information theory has been developed for objective and discrete information. Can information theory be extended to this theory to incorporate multiple forms of information, each with its own (physical) carriers and dynamics? Here, I will not review all the possible roles that information can play, but rather what conditions an appropriate theory should satisfy. The most promising starting point is provided by entropy measures of conditional probabilities (using the so-called Kullback–Leibler divergence), allowing an assessment of how acquiring information can lead to an increase in fitness. It is irrelevant (to a certain extent) where the information comes from—genes, experience or culture—but it is important to realize that information is not merely subjective but its value should be evaluated in fitness terms, and it is here that evolutionary theory has an enormous potential. A number of important stumbling points remain, however; namely, the identification of whose fitness it concerns and what role the spatio-temporal dynamics plays (which is tightly linked to the nature of the physical carriers of the information and the processes that impact on it).


2020 ◽  
Vol 637 ◽  
pp. 117-140 ◽  
Author(s):  
DW McGowan ◽  
ED Goldstein ◽  
ML Arimitsu ◽  
AL Deary ◽  
O Ormseth ◽  
...  

Pacific capelin Mallotus catervarius are planktivorous small pelagic fish that serve an intermediate trophic role in marine food webs. Due to the lack of a directed fishery or monitoring of capelin in the Northeast Pacific, limited information is available on their distribution and abundance, and how spatio-temporal fluctuations in capelin density affect their availability as prey. To provide information on life history, spatial patterns, and population dynamics of capelin in the Gulf of Alaska (GOA), we modeled distributions of spawning habitat and larval dispersal, and synthesized spatially indexed data from multiple independent sources from 1996 to 2016. Potential capelin spawning areas were broadly distributed across the GOA. Models of larval drift show the GOA’s advective circulation patterns disperse capelin larvae over the continental shelf and upper slope, indicating potential connections between spawning areas and observed offshore distributions that are influenced by the location and timing of spawning. Spatial overlap in composite distributions of larval and age-1+ fish was used to identify core areas where capelin consistently occur and concentrate. Capelin primarily occupy shelf waters near the Kodiak Archipelago, and are patchily distributed across the GOA shelf and inshore waters. Interannual variations in abundance along with spatio-temporal differences in density indicate that the availability of capelin to predators and monitoring surveys is highly variable in the GOA. We demonstrate that the limitations of individual data series can be compensated for by integrating multiple data sources to monitor fluctuations in distributions and abundance trends of an ecologically important species across a large marine ecosystem.


Ecohydrology ◽  
2021 ◽  
Author(s):  
Qiongfang Li ◽  
Yuting Zhu ◽  
Qihui Chen ◽  
Yu Li ◽  
Jing Chen ◽  
...  

2021 ◽  
Vol 13 (9) ◽  
pp. 4926
Author(s):  
Nguyen Duc Luong ◽  
Nguyen Hoang Hiep ◽  
Thi Hieu Bui

The increasing serious droughts recently might have significant impacts on socioeconomic development in the Red River basin (RRB). This study applied the variable infiltration capacity (VIC) model to investigate spatio-temporal dynamics of soil moisture in the northeast, northwest, and Red River Delta (RRD) regions of the RRB part belongs to territory of Vietnam. The soil moisture dataset simulated for 10 years (2005–2014) was utilized to establish the soil moisture anomaly percentage index (SMAPI) for assessing intensity of agricultural drought. Soil moisture appeared to co-vary with precipitation, air temperature, evapotranspiration, and various features of land cover, topography, and soil type in three regions of the RRB. SMAPI analysis revealed that more areas in the northeast experienced severe droughts compared to those in other regions, especially in the dry season and transitional months. Meanwhile, the northwest mainly suffered from mild drought and a slightly wet condition during the dry season. Different from that, the RRD mainly had moderately to very wet conditions throughout the year. The areas of both agricultural and forested lands associated with severe drought in the dry season were larger than those in the wet season. Generally, VIC-based soil moisture approach offered a feasible solution for improving soil moisture and agricultural drought monitoring capabilities at the regional scale.


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