Efficacy of a computer-based cognitive training program to enhance planning skills in 5 to 7-year-old normally-developing children.

We designed and evaluated the efficacy of a computer-based cognitive training program (Executive Function Enhancement Program [EFEP]) to stimulate executive functions through enhancing planning in normally-developing children. A total of 111 Colombian children participated in the study. Fifty-nine (53%) of the children were assigned to the experimental condition (application of the EFEP program) with two levels of planning performance, and fifty-two (47%) to the waiting list control condition with the same two levels of planning. The training program was applied three times a week over six weeks, with post-intervention assessment two weeks after the end of training. A follow-up assessment was carried out three months later. Results showed that the intervention program was particularly effective in the children with lower pre-intervention performance in planning, demonstrating that the program is an efficient therapeutic instrument for enhancing the executive function of planning in children between 5 and 7 years old.

Processing of task-irrelevant words of different frequency values: a visual mismatch negativity study.

This study examined electrophysiological correlates of early and automatic word access. Chinese single-character words of high frequency and low frequency were peripherally presented in an oddball paradigm. Participants were instructed to carry out a centrally presented nonlinguistic colour-tracking task and ignore the lexical stimuli presented on both sides. Early visual mismatch negativity (vMMN) effects at 120-150 and 200-300 ms were elicited only by high-frequency characters, whereas low-frequency characters yielded vMMN only after 300 ms. This contrast of vMMN effects indicating lexical processing in an attention-deprived condition is suggested to result from stronger memory traces for high-frequency characters in comparison with low-frequency characters.

Early lexical processing of Chinese words indexed by Visual Mismatch Negativity effects.

Although Mismatch Negativity (MMN) effects indicating early, automatic lexical processing have been reported in the auditory language modality, so far these have not been reliably obtained in MMN studies of visual word recognition. The present study explores this discrepancy by investigating whether visual MMN (vMMN) effects can be obtained in written Chinese single-character word recognition. While participants were engaged in a non-linguistic distraction task, we measured Event-Related Potentials (ERPs) time-locked to perifoveally-presented real and pseudo- characters matched in overall visual-orthographic attributes. VMMN was defined as significant difference between the ERPs to characters presented as deviants or as standards in a context of non-characters. For the native Chinese readers, af ter sub-lexical structural detection from 120-160 ms, only real characters elicited vMMN at the interval of 170-210 ms, suggesting that lexical information in Chinese words is processed early and automatically. In a later window of 340-380 ms, both real and pseudo- characters yielded vMMNs. In a control group of non-Chinese participants, no evidence of vMMN was found for either real or pseudo-characters. Taken together, these results suggest that long-term memory representations for real characters may enable their early processing even in unattended conditions.

Written-Word Concreteness Effects in Non-attend Conditions: Evidence From Mismatch Responses and Cortical Oscillations.

It has been widely reported that concrete words have processing advantages over abstract words in terms of speed and efficiency of processing, a phenomenon known as the concreteness effect. However, little is still known about the early time-course of processing concrete and abstract words and whether this concreteness effect can still persist in conditions where attention is not focused on the words presented (automatic processing). This study aimed to shed light on these issues by examining the electrophysiological brain responses to concrete and abstract words. While participants were engaged in a non-linguistic color tracking task presented in the center of the monitor screen, matched Chinese concrete and abstract single-character words appeared within a passive oddball paradigm, out of the focus of attention. In calculating visual Mismatch Negativity (vMMN), Event-related potentials (ERPs) to words of the same semantic category were compared when these words were presented as deviants and standards. Before 320 ms, both abstract and concrete words yielded vMMN with left-lateralized distribution, suggesting similar verbal processing at an initial processing stage. After 320 ms, only concrete words additionally elicited vMMN with a central distribution. Time frequency (TF) analysis of the results also revealed larger theta power increase (200-300 ms) and theta power phase locking (200-450 ms) for concrete than for abstract words. Interestingly, there was more alpha power decrease for abstract than for concrete words from 300 to 450 ms. This may reflect the greater difficulty in processing abstract meaning. Taken together, our ERP and TF results point to the existence of different neural mechanisms underlying non-attentive processing of abstract and concrete words.

When "He" Can Also Be "She": An ERP Study of Reflexive Pronoun Resolution in Written Mandarin Chinese.

The gender information in written Chinese third person pronouns is not symmetrically encoded: the character for "he" (, with semantic radical , meaning human) is used as a default referring to every individual, while the character for "she" (, with semantic radical , meaning woman) indicates females only. This critical feature could result in different patterns of processing of gender information in text, but this is an issue that has seldom been addressed in psycholinguistics. In Chinese, the written forms of the reflexive pronouns are composed of a pronoun plus the reflexive "/self" (/himself and /herself). The present study focuses on how such gender specificity interacts with the gender type of an antecedent, whether definitional (proper name) or stereotypical (stereotypical role noun) during reflexive pronoun resolution. In this event-related potential (ERP) study, gender congruity between a reflexive pronoun and its antecedent was studied by manipulating the gender type of antecedents and the gender specificity of reflexive pronouns (default: /himself vs. specific: /herself). Results included a P200 "attention related" congruity effect for /himself and a P600 "integration difficulty" congruity effect for /herself. Reflexive pronoun specificity independently affected the P200 and N400 components. These results highlight the role of /himself as a default applicable to both genders and indicate that only the processing of /herself supports a two-stage model for anaphor resolution. While both reflexive pronouns are evaluated at the bonding stage, the processing of the gender-specific reflexive pronoun is completed in the resolution stage.

Differential oscillatory encoding of foreign speech.

Neuronal oscillations play a key role in auditory perception of verbal input, with the oscillatory rhythms of the brain showing synchronization with specific frequencies of speech. Here we investigated the neural oscillatory patterns associated with perceiving native, foreign, and unknown speech. Spectral power and phase synchronization were compared to those of a silent context. Power synchronization to native speech was found in frequency ranges corresponding to the theta band, while no synchronization patterns were found for the foreign speech context and the unknown language context. For phase synchrony, the native and unknown languages showed higher synchronization in the theta-band than the foreign language when compared to the silent condition. These results suggest that neural synchronization patterns are markedly different for native and foreign languages.

Complex brain network properties in late L2 learners and native speakers.

Whether the neural mechanisms that underlie the processing of a second language in highly proficient late bilinguals (L2 late learners) are similar or not to those that underlie the processing of the first language (L1) is still an issue under debate. In this study, a group of late learners of Spanish whose native language is English and a group of Spanish monolinguals were compared while they read sentences, some of which contained syntactic violations. A brain complex network analysis approach was used to assess the time-varying topological properties of the functional networks extracted from the electroencephalography (EEG) recording. Late L2 learners showed a lower degree of parallel information transfer and a slower propagation between regions of the brain functional networks while processing sentences containing a gender mismatch condition as compared with a standard sentence configuration. In contrast, no such differences between these conditions were detected in the Spanish monolinguals. This indicates that when a morphosyntactic language incongruence that does not exist in the native language is presented in the second language, the neural activation pattern is configured differently in highly proficient late bilinguals than in monolinguals.

Anatomical connectivity changes in the bilingual brain.

How the brain deals with more than one language and whether we need different or extra brain language sub-networks to support more than one language remain unanswered questions. Here, we investigate structural brain network differences between early bilinguals and monolinguals. Using diffusion-weighted MRI (DW-MRI) tractography techniques and a network-based statistic (NBS) procedure, we found two structural sub-networks more connected by white matter (WM) tracts in bilinguals than in monolinguals; confirming WM brain plasticity in bilinguals. One of these sub-networks comprises left frontal and parietal/temporal regions, while the other comprises left occipital and parietal/temporal regions and also the right superior frontal gyrus. Most of these regions have been related to language processing and monitoring; suggesting that bilinguals develop specialized language sub-networks to deal with the two languages. Additionally, a complex network analysis showed that these sub-networks are more graph-efficient in bilinguals than monolinguals and this increase seems to be at the expense of a whole-network graph-efficiency decrease.

Are vowels and consonants processed differently? Event-related potential evidence with a delayed letter paradigm.

To investigate the neural bases of consonant and vowel processing, event-related potentials (ERPs) were recorded while participants read words and pseudowords in a lexical decision task. The stimuli were displayed in three different conditions: (i) simultaneous presentation of all letters (baseline condition); (ii) presentation of all letters, except that two internal consonants were delayed for 50 msec (consonants-delayed condition); and (iii) presentation of all letters, except that two internal vowels were delayed for 50 msec (vowels-delayed condition). The behavioral results showed that, for words, response times in the consonants-delayed condition were longer than in the vowels-delayed condition, which, in turn, were longer than in the baseline condition. The ERPs showed that, starting as early as 150 msec, words in the consonants-delayed condition produced a larger negativity than words in vowels-delayed condition. In addition, there were peak latency differences and amplitude differences in the P150, N250, P325, and N400 components between the baseline and the two letter-delayed conditions. We examine the implications of these findings for models of visual-word recognition and reading.

Modulations of 'late' event-related brain potentials in humans by dynamic audiovisual speech stimuli.

Lipreading reliably improve speech perception during face-to-face conversation. Within the range of good dubbing, however, adults tolerate some audiovisual (AV) discrepancies and lipreading, then, can give rise to confusion. We used event-related brain potentials (ERPs) to study the perceptual strategies governing the intermodal processing of dynamic and bimodal speech stimuli, either congruently dubbed or not. Electrophysiological analyses revealed that non-coherent audiovisual dubbings modulated in amplitude an endogenous ERP component, the N300, we compared to a 'N400-like effect' reflecting the difficulty to integrate these conflicting pieces of information. This result adds further support for the existence of a cerebral system underlying 'integrative processes' lato sensu. Further studies should take advantage of this 'N400-like effect' with AV speech stimuli to open new perspectives in the domain of psycholinguistics.