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Humans can extract statistical regularities of the environment to predict upcoming events. Previous research recognized that implicitly acquired statistical knowledge remained persistent and continued to influence behavior even when the regularities were no longer present in the environment. Here, in an fMRI experiment, we investigated how the persistence of statistical knowledge is represented in the brain. Participants (n = 32) completed a visual, four-choice, RT task consisting of statistical regularities. Two types of blocks constantly alternated with one another throughout the task: predictable statistical regularities in one block type and unpredictable ones in the other. Participants were unaware of the statistical regularities and their changing distribution across the blocks. Yet, they acquired the statistical regularities and showed significant statistical knowledge at the behavioral level not only in the predictable blocks but also in the unpredictable ones, albeit to a smaller extent. Brain activity in a range of cortical and subcortical areas, including early visual cortex, the insula, the right inferior frontal gyrus, and the right globus pallidus/putamen contributed to the acquisition of statistical regularities. The right insula, inferior frontal gyrus, and hippocampus as well as the bilateral angular gyrus seemed to play a role in maintaining this statistical knowledge. The results altogether suggest that statistical knowledge could be exploited in a relevant, predictable context as well as transmitted to and retrieved in an irrelevant context without a predictable structure. [ABSTRACT FROM AUTHOR]

Objectives: Stress "deafness" is a difficulty in the detection of stress pattern changes of second language (L2) words. This study investigated the influence of cognitive factors and L2 proficiency on the processing of L2 stress. Methodology: Fifty-four native speakers of Hungarian, a language with non-contrastive stress, participated in the study; the participants were categorized as not speaking German or having a proficiency at the intermediate or advanced level. They had to recall sequences with increasing length consisting of German pseudowords that differed in either their phonemes (phoneme task) or stress patterns (stress task). Cognitive factors measured included working memory, phonological awareness and inhibitory control. Data and Analysis: The accuracy data obtained in the sequence recall task was analysed with generalized linear mixed modelling. Two separate analyses were performed to investigate the presence of stress "deafness" and the effect of cognitive factors. Findings: Results showed that the stress task led to lower performance than the phoneme task, irrespective of L2 proficiency. Furthermore, the analysis showed different cognitive factors contributing to the performance in the tasks: in the phoneme task, it was working memory, phonological awareness and inhibitory control, while in the stress task, it was only working memory and phonological awareness but not the inhibitory control. Originality: This is the first study to provide evidence about the cognitive background of the stress "deafness" effect, and to suggest the differential role of inhibitory control in phoneme and stress processing. Implications: These findings demonstrate the robustness of the stress "deafness" effect in a language with non-contrastive stress, provide evidence of the effect being independent of L2 proficiency and suggest that speakers of languages with non-contrastive stress do not have the necessary cognitive basis to form accurate L2 stress representations. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the role of executive functions ( EFs) in different strategies underlying risky decision making. Adult participants from a nonclinical sample were assigned to low or high EF groups based on their performance on EF tasks measuring shifting, updating, and inhibition. ERPs were recorded while participants performed the Balloon Analogue Risk Task ( BART). In this task, each balloon pump was associated with either a reward or a balloon pop with unknown probability. The BART behavioral measures did not show between-group differences. However, the feedback-related negativity ( FRN) associated with undesirable outcomes was larger in the high EF group than in the low EF group. Since the FRN represents salience prediction error, our results suggest that the high EF group formed internal models that were violated by the outcomes. Thus, we provided ERP evidence for EFs influencing risky decision-making processes. [ABSTRACT FROM AUTHOR]

Verbal fluency tasks are commonly used in cognitive and developmental neuropsychology in assessing executive functions, language skills as well as divergent thinking. Twenty-two typically developing children and 22 children with ADHD between the ages of 8 and12 years were examined using verbal fluency tasks, prepotent response inhibition, and working memory tests. The clinical group showed impaired inhibitory and spatial working memory processes. We used different qualitative analyses of verbal fluency tasks to explore the lexical and executive strategies (word clustering and switching), and the temporal properties of the responses. Children with ADHD had a leeway in applying relevant lexical or executive strategies related to difficulties in strategy using. The reduced efficiency of children with ADHD in semantic fluency task is based on suboptimal shifting between word clusters and is related to the lack of ability of producing new clusters of items. The group difference appeared at the level of accessing and/or activating common words; however, the executive process of searching the lexicon extensively is intact. [ABSTRACT FROM PUBLISHER]

Humans are capable of acquiring multiple types of information presented in the same information stream. It has been suggested that at least two parallel learning processes are important during learning of sequential patterns-statistical learning and rule-based learning. Yet, the neurophysiological underpinnings of these parallel learning processes are not fully understood. To differentiate between the simultaneous mechanisms at the single trial level, we apply a temporal EEG signal decomposition approach together with sLORETA source localization method to delineate whether distinct statistical and rule-based learning codes can be distinguished in EEG data and can be related to distinct functional neuroanatomical structures. We demonstrate that concomitant but distinct aspects of information coded in the N2 time window play a role in these mechanisms: mismatch detection and response control underlie statistical learning and rule-based learning, respectively, albeit with different levels of time-sensitivity. Moreover, the effects of the two learning mechanisms in the different temporally decomposed clusters of neural activity also differed from each other in neural sources. Importantly, the right inferior frontal cortex (BA44) was specifically implicated in visuomotor statistical learning, confirming its role in the acquisition of transitional probabilities. In contrast, visuomotor rule-based learning was associated with the prefrontal gyrus (BA6). The results show how simultaneous learning mechanisms operate at the neurophysiological level and are orchestrated by distinct prefrontal cortical areas. The current findings deepen our understanding on the mechanisms of how humans are capable of learning multiple types of information from the same stimulus stream in a parallel fashion., (© 2021 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.)