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1.
Cereb Cortex ; 33(13): 8783-8791, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37160328

RESUMO

It is now well established that reading words in a second language (L2) automatically activates native language (L1) translations in bilinguals. Although there is evidence that access to such representations is inhibited when words have a negative emotional valence, the mechanism underlying such inhibition is elusive, and it is unknown whether inhibition arises online as L2 is being processed or whether negative valence affects subsequent L1 processing. Here, we recorded event-related brain potentials in Chinese-English bilinguals engaged in an implicit translation-priming paradigm involving L2 (English) word pairs. Participants performed a semantic relatedness task, unaware that word pairs could conceal a sound repetition if translated into Chinese. When emotional valence was manipulated in prime position (first word), we observed form repetition priming through L1 translations for positive but not for negative words. However, when emotional valence was manipulated in target position (second word), priming occurred for both positive and negative word valences. This result begins to elucidate the mechanism by which emotion regulates language processing in bilinguals: Negative words in L2 induce a refractory period during which cross-language lexical access is blocked. These findings show that despite being neuroanatomically distinct in the human brain, emotional (limbic) regulation systems can penetrate language processing.


Assuntos
Multilinguismo , Humanos , Leitura , Idioma , Encéfalo/fisiologia , Emoções/fisiologia
2.
Eur J Neurosci ; 57(5): 840-853, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36656284

RESUMO

How speaking two languages affects executive functions has been a long-standing debate and the mechanisms underlying the observed cognitive advantages of bilingualism remain unspecified. Here, using multivariate pattern classification methods, we decoded spatial patterns of neural signals associated with Flanker task performance in mono-dialectal and bi-dialectal speakers of Chinese. While univariate approach to even-related potentials (ERPs) showed no between-group difference, decoding accuracy of ERPs was reduced in bi-dialectal as compared to mono-dialectal speakers in both congruent-neutral and incongruent-neutral classifications. There was no effect of bidialectalism, however, on decoding accuracy of alpha-band oscillations, an electrophysiological index implicated in inhibition. Behavioural data analysed using the Drift Diffusion Model (DDM) showed facilitating effects of bidialectalism on non-decision times but no effect on drift rates. These findings demonstrate that using two dialects on a daily basis enhances general attentional deployment rather than affecting specific component of executive functions such as inhibitory control. Given that the two dialects of Chinese differed almost exclusively in phonology, the bidialectalism effect was most likely motivated by resolving phonological competition at lexical processing level.


Assuntos
Função Executiva , Multilinguismo , Função Executiva/fisiologia , Idioma , Atenção/fisiologia
3.
BMC Neurosci ; 22(1): 36, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34000982

RESUMO

BACKGROUND: The neural networks underpinning language control and domain-general executive functions overlap in bilinguals, but existing evidence is mainly correlative. Here, we present the first neurofunctional evidence for a transfer effect between (domain-general) inhibitory control and language control through training. We trained Chinese-English bilinguals for 8 days using a Simon task taxing the inhibitory control system, whilst an active control group was trained with a color judgment task that does not tax the inhibitory control system. All participants performed a language-switching task before and after training. It has been suggested that the activity of the left DLPFC was associated with domain-general top-down cognitive control (Macdonald et al. Science 288: 1835-1838, 2000) and bilingual language control (Wang et al. Neuroimage 35: 862-870, 2007). In addition, the dACC was closely related to the conflict detection (Abutalebi et al. Cereb Cortex 18:1496-1505, 2008). Last, the activity of the left caudate has been linked with lexical selection (Abutalebi et al. Cereb Cortex 18:1496-1505, 2008), especially the selection of the weak language (Abutalebi et al. Cortex 49: 905-911, 2013). Therefore, we focused on these three regions of interest (ROIs) where neural changes associated with transfer were expected to occur. RESULTS: The results showed a negative correlation between changes in activation levels in the left dorsolateral prefrontal cortex (DLPFC) and changes in the switch cost magnitude in the language-switching task in the training group but not in the control group, suggesting that the DLPFC plays a critical role in the transfer effect from domain-general executive functions to language control. However, there was no measurable effect in the anterior cingulate cortex or left caudate nucleus, suggesting that the inhibitory control training increased the neural efficiency for language production in bilinguals in terms of attention shifting and conflict resolution, but the training did not affect conflict detection and lexical selection. CONCLUSION: These findings showed how cognitive training evidence can help establish a causational link between the neural basis of domain-general executive functions and language control in bilinguals.


Assuntos
Encéfalo/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Multilinguismo , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Adulto Jovem
4.
Neuroimage ; 203: 116180, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31520745

RESUMO

The ability to conceive time is a corner stone of human cognition. It is unknown, however, whether time conceptualisation differs depending on language of operation in bilinguals. Whilst both Chinese and English cultures associate the future with the front space, some temporal expressions of Chinese involve a configuration reversal due to historic reasons. For instance, Chinese refers to the day after tomorrow using the spatiotemporal metaphor hou-tian - 'back-day' and to the day before yesterday using qian-tian - 'front-day'. Here, we show that native metaphors interfere with time conceptualisation when bilinguals operate in the second language. We asked Chinese-English bilinguals to indicate whether an auditory stimulus depicted a day of the week either one or two days away from the present day, irrespective of whether it referred to the past or the future, and ignoring whether it was presented through loudspeakers situated in the back or the front space. Stimulus configurations incongruent with spatiotemporal metaphors of Chinese (e.g., "Friday" presented in the front of the participant during a session held on a Wednesday) were conceptually more challenging than congruent configurations (e.g., the same stimulus presented in their back), as indexed by N400 modulations of event-related brain potentials. The same pattern obtained for days or years as stimuli, but surprisingly, it was found only when participants operated in English, not in Chinese. We contend that the task was easier and less prone to induce cross-language activation when conducted in the native language. We thus show that, when they operate in the second language, bilinguals unconsciously retrieve irrelevant native language representations that shape time conceptualisation in real time.


Assuntos
Encéfalo/fisiologia , Multilinguismo , Semântica , Percepção do Tempo/fisiologia , Estimulação Acústica , Percepção Auditiva/fisiologia , Eletroencefalografia , Potenciais Evocados , Humanos , Metáfora
5.
Hum Brain Mapp ; 40(8): 2434-2448, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30697881

RESUMO

Processing affective prosody, that is the emotional tone of a speaker, is fundamental to human communication and adaptive behaviors. Previous studies have mainly focused on adults and infants; thus the neural mechanisms underlying the processing of affective prosody in newborns remain unclear. Here, we used near-infrared spectroscopy to examine the ability of 0-to-4-day-old neonates to discriminate emotions conveyed by speech prosody in their maternal language and a foreign language. Happy, fearful, and angry prosodies enhanced neural activation in the right superior temporal gyrus relative to neutral prosody in the maternal but not the foreign language. Happy prosody elicited greater activation than negative prosody in the left superior frontal gyrus and the left angular gyrus, regions that have not been associated with affective prosody processing in infants or adults. These findings suggest that sensitivity to affective prosody is formed through prenatal exposure to vocal stimuli of the maternal language. Furthermore, the sensitive neural correlates appeared more distributed in neonates than infants, indicating a high-level of neural specialization between the neonatal stage and early infancy. Finally, neonates showed preferential neural responses to positive over negative prosody, which is contrary to the "negativity bias" phenomenon established in adult and infant studies.


Assuntos
Emoções/fisiologia , Neuroimagem Funcional , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Percepção Social , Espectroscopia de Luz Próxima ao Infravermelho , Percepção da Fala/fisiologia , Feminino , Humanos , Recém-Nascido , Masculino , Lobo Parietal/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem
6.
J Neurosci ; 33(33): 13533-7, 2013 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-23946411

RESUMO

Mastering two languages has been associated with enhancement in human executive control, but previous studies of this phenomenon have exclusively relied on comparisons between bilingual and monolingual individuals. In the present study, we tested a single group of Welsh-English bilinguals engaged in a nonverbal conflict resolution task and manipulated language context by intermittently presenting words in Welsh, English, or both languages. Surprisingly, participants showed enhanced executive capacity to resolve interference when exposed to a mixed compared with a single language context, even though they ignored the irrelevant contextual words. This result was supported by greater response accuracy and reduced amplitude of the P300, an electrophysiological correlate of cognitive interference. Our findings introduce a new level of plasticity in bilingual executive control dependent on fast changing language context rather than long-term language experience.


Assuntos
Encéfalo/fisiologia , Função Executiva/fisiologia , Multilinguismo , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Humanos , Idioma , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
7.
J Neurosci ; 32(19): 6485-9, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22573670

RESUMO

Reading words in a second language spontaneously activates native language translations in the human bilingual mind. Here, we show that the emotional valence of a word presented in English constrains unconscious access to its Chinese translation. We asked native speakers of Chinese fluent with English to indicate whether or not pairs of English words were related in meaning while monitoring their brain electrical activity. Unbeknownst to the participants, some of the word pairs hid a sound repetition if translated into Chinese. Remarkably, English words with a negative valence such as "violence" did not automatically activate their Chinese translation, even though we observed the expected sound repetition priming effect for positive and neutral words, such as "holiday" and "theory." These findings show that emotion conveyed by words determines language activation in bilinguals, where potentially disturbing stimuli trigger inhibitory mechanisms that block access to the native language.


Assuntos
Emoções/fisiologia , Coração/fisiologia , Multilinguismo , Estimulação Luminosa/métodos , Leitura , Adolescente , Adulto , Feminino , Humanos , Idioma , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
8.
Cereb Cortex ; 22(3): 577-83, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21680846

RESUMO

The attentional effects triggered by emotional stimuli in humans have been substantially investigated, but little is known about the impact of affective valence on the processing of meaning. Here, we used a cross-modal priming paradigm involving visually presented adjective-noun dyads and environmental sounds of controlled affective valence to test the contributions of conceptual relatedness and emotional congruence to priming. Participants undergoing event-related potential recording indicated whether target environmental sounds were related in meaning to adjective-noun dyads presented as primes. We tested spontaneous emotional priming by manipulating the congruence between the affective valence of the adjective in the prime and that of the sound. While the N400 was significantly reduced in amplitude by both conceptual relatedness and emotional congruence, there was no interaction between the 2 factors. The same pattern of results was found when participants judged the emotional congruence between environmental sounds and adjective-noun dyads. These results support the hypothesis that conceptual and emotional processes are functionally independent regardless of the specific cognitive focus of the comprehender.


Assuntos
Aprendizagem por Associação/fisiologia , Percepção Auditiva/fisiologia , Córtex Cerebral/fisiologia , Emoções/fisiologia , Meio Ambiente , Potenciais Evocados Auditivos/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Potenciais Evocados/fisiologia , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Psicoacústica , Tempo de Reação/fisiologia
9.
Brain Struct Funct ; 228(2): 635-649, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36585969

RESUMO

Research has shown that several variables affect language control among bilingual speakers but the effect of affective processing remains unexplored. Chinese-English bilinguals participated in a novel prime-target language switching experiment in which they first judged the affective valence (i.e., positive or negative) of auditorily presented words and then named pictures with neutral emotional valence in either the same (non-switch trial) or different language (switch trial). Brain activity was monitored using functional magnetic resonance imaging (fMRI). The behavioral performance showed that the typical switch cost (i.e., the calculated difference between switch and non-switch trials) emerged after processing positive words but not after negative words. Brain imaging demonstrated that processing negative words immediately before non-switch picturing naming trials (but not for switch trials) increased activation in brain areas associated with domain-general cognitive control. The opposite patterns were found after processing positive words. These findings suggest that an (emotional) negative priming effect is induced by spontaneous exposure to negative words and that these priming effects may be triggered by reactive emotional processing and that they may interact with higher level cognitive functions.


Assuntos
Multilinguismo , Idioma , Encéfalo/fisiologia , Emoções/fisiologia , Mapeamento Encefálico
10.
J Affect Disord ; 330: 165-172, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36828149

RESUMO

BACKGROUND: Adolescent mental health is influenced by various adverse environmental conditions. However, it remains unclear how these factors jointly affect adolescent depression. This study aimed to use network analysis to assess the associations between different environmental factors and depressive symptoms in adolescents and to identify key pathways between them. METHODS: This study included 610 adolescents with depression from inpatient and outpatient units recruited between March 2020 and November 2021. The mean age was 14.86 ± 1.96, with no significant difference between males (n = 155, 15.10 ± 2.19) and females (n = 455, 14.78 ± 1.88). Depressive symptoms were measured using the Children's Depression Inventory, and individual risk environment factors included childhood trauma, social peer and family risk factors. Network features, including network centrality, stability, and bridge centrality, were investigated. RESULTS: Anhedonia and self-esteem were found to be more central in depressive symptoms. Insult experiences from the social peer and emotional abuse experience from childhood were more central environmental factors. Childhood trauma experiences were more related to adolescent depressive symptoms compared to family and peer factors. Bridge analyses identified emotional abuse, emotional neglect and physical neglect as the main bridges linking environment risk to depressive symptoms. LIMITATIONS: This was a cross-sectionally designed study, which limited its ability to examine longitudinal dynamic interactions between environmental factors and adolescent depressive symptoms. CONCLUSIONS: Our findings suggested that childhood trauma experiences might have greater psychological impacts on adolescent depression than family and social peer environments, and should be considered as crucial targets for preventing severe depressive moods.


Assuntos
Depressão , Grupo Associado , Masculino , Criança , Feminino , Humanos , Adolescente , Depressão/epidemiologia , Depressão/psicologia , Saúde Mental , Meio Social , Autoimagem , Fatores de Risco
11.
Neuroimage ; 59(4): 3468-73, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22155033

RESUMO

It is generally accepted that word processing in bilinguals is language nonselective. However, this has mostly been shown in contexts involving deliberate processing focusing on a particular aspect of linguistic information (e.g., lexicality, semantic category, relatedness). It is therefore unknown to what extent non-target language access is only apparent in overt language processing contexts. Here, we examined the effect of involuntary word processing in bilingual individuals performing a nonverbal judgment task on shapes. Chinese-English bilinguals had to differentiate between circles and squares by pressing buttons while ignoring intervening English words. In the critical trials, the to-be-ignored words concealed a sound repetition with the words "circle" or "square" when translated into Chinese. In these trials, we found increased N200 event-related potential amplitudes, reflecting inhibition in this condition as compared to the control condition, in which the intervening words were totally unrelated to the shapes. Since no lateralised readiness potential effect was found in this comparison, access to Chinese translations must have been quickly inhibited, consistent with the fact that we observed no behavioural effects of the hidden manipulation. These results suggest fast and unconscious language nonselective access even when no language task is being performed.


Assuntos
Processos Mentais/fisiologia , Multilinguismo , Tradução , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
12.
Nat Hum Behav ; 6(8): 1169-1179, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35654965

RESUMO

Human neonates can discriminate phonemes, but the neural mechanism underlying this ability is poorly understood. Here we show that the neonatal brain can learn to discriminate natural vowels from backward vowels, a contrast unlikely to have been learnt in the womb. Using functional near-infrared spectroscopy, we examined the neuroplastic changes caused by 5 h of postnatal exposure to random sequences of natural and reversed (backward) vowels (T1), and again 2 h later (T2). Neonates in the experimental group were trained with the same stimuli as those used at T1 and T2. Compared with controls, infants in the experimental group showed shorter haemodynamic response latencies for forward vs backward vowels at T1, maximally over the inferior frontal region. At T2, neural activity differentially increased, maximally over superior temporal regions and the left inferior parietal region. Neonates thus exhibit ultra-fast tuning to natural phonemes in the first hours after birth.


Assuntos
Percepção da Fala , Encéfalo/fisiologia , Lobo Frontal , Humanos , Lactente , Recém-Nascido , Aprendizagem , Lobo Parietal/diagnóstico por imagem , Percepção da Fala/fisiologia
13.
J Neurosci ; 30(22): 7646-51, 2010 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-20519539

RESUMO

Bilingual individuals have been shown to access their native language while reading in or listening to their other language. However, it is unknown what type of mental representation (e.g., sound or spelling) they retrieve. Here, using event-related brain potentials, we demonstrate unconscious access to the sound form of Chinese words when advanced Chinese-English bilinguals read or listen to English words. Participants were asked to decide whether or not English words presented in pairs were related in meaning; they were unaware of the fact that some of the unrelated word pairs concealed either a sound or a spelling repetition in their Chinese translations. Whereas spelling repetition in Chinese translations had no effect, concealed sound repetition significantly modulated event-related brain potentials. These results suggest that processing second language activates the sound, but not the spelling, of native language translations.


Assuntos
Compreensão/fisiologia , Audição/fisiologia , Multilinguismo , Leitura , Traduções , Estimulação Acústica/métodos , Adulto , Análise de Variância , Povo Asiático , Eletroencefalografia/métodos , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Testes de Linguagem , Masculino , Fonética , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Semântica , Vocabulário , Adulto Jovem
14.
Front Psychol ; 11: 791, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425858

RESUMO

Language switching involves multiple processing stages. Previous studies have not dissociated the cognitive process underlying language form switches and concept switches. Here, we examined the two factors using a novel language-switching paradigm. Chinese-English bilinguals named individually presented pictures in either Chinese or English according to a language cue. Pictures in two consecutive trials represented either identical, semantically related, or unrelated concepts. Results showed both language (form) switch costs and concept switch costs. The interaction between these two factors suggested that the effects were additive, with the longest naming response times observed when two pictures were semantically unrelated and involved a switch between languages. These findings suggest that the functional loci of the language control mechanism occur at multiple processing stages. Implications of the findings are discussed within current models of language processing in bilinguals.

15.
Psychophysiology ; 57(8): e13562, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32149394

RESUMO

Empathy for others' pain plays a critical role in human social interactions, but the influence of language contexts remains unclear. We examined the foreign-language effect on the behavioral and the underlying neural processes of empathy for others' pain. Chinese-English bilinguals performed a pain empathy task separately in Chinese (native language) and English (foreign language) contexts while event-related potentials (ERPs) were recorded. Results showed that bilingual participants reported greater ratings of perceived pain intensity in response to the observation of others' pain in the English as compared to the Chinese context. When comparing the brain responses to painful stimuli with those to non-painful stimuli, a significant empathic response in the early ERP component (N1) was found only in the English, but not in the Chinese context. Empathic response in the P3 component was larger when bilingual participants performed the task in English as compared to Chinese. However, empathic response in the late positive potential (LPP) was comparable between these two language contexts. Furthermore, spontaneous fronto-central α-oscillation power recorded prior to the onset of empathic stimuli was significantly lower in the foreign language as compared to the native-language context. These findings demonstrated a foreign-language effect on both the automatic affective sharing and the top-down cognitive evaluation processes of empathy for others' pain. This effect is most likely to be the result of altered brain states, involving increased vigilance and arousal level when bilingual individuals function in a foreign-language context.


Assuntos
Ritmo alfa/fisiologia , Empatia/fisiologia , Potenciais Evocados/fisiologia , Multilinguismo , Percepção Social , Adulto , Feminino , Humanos , Masculino , Dor/psicologia , Adulto Jovem
16.
Brain Lang ; 194: 23-34, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30991263

RESUMO

In bilingual speakers, language switching might involve a change in language form, meaning, or both. However, the neural substrates of language control in the three switching conditions have not been specified. We examined bilingual speech production using a picture-naming paradigm that teased apart language and semantic switching. Bilingual participants named two serially presented pictures, which show the same or different object, with one or two languages. The three switching conditions showed distinct neural activation patterns within the prefrontal cortex. Moreover, neural substrates shared by all switching conditions were primarily found in fronto-parietal regions. Besides, forward switching (L1-to-L2) activated a more widespread neural network than backward switching (L2-to-L1). We discuss differential engagement of the cognitive control system as a function of switching type during bilingual speech production.


Assuntos
Multilinguismo , Córtex Pré-Frontal/fisiologia , Adulto , Feminino , Humanos , Masculino , Semântica , Fala , Voz , Adulto Jovem
17.
Brain Struct Funct ; 224(7): 2357-2371, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31222427

RESUMO

Previous research has shown that training on inhibitory control (IC) leads to functional neural plastic changes, although this effect on individuals with different levels of IC abilities has yet to be studied. Here, we examined the individual differences in IC abilities of 85 participants, who performed a Simon task while undergoing a functional magnetic resonance imaging (fMRI) scan. Participants in the experimental group followed an 8-day training session on IC between the pre- and the post-test, whereas the control group did not receive any training. The fMRI results reported that, in comparison to the control group, the training session elicited different patterns of neural adaptation between participants with high- and low-IC abilities in the experimental group. While training reduced activation levels in the supplementary motor area (SMA), bilateral thalamus, and left anterior cingulate cortex (ACC) of individuals with low-IC performance prior to the training, the same pattern was not found in participants with high-IC performance. In addition, individual differences in IC abilities before training also positively correlated with activation reduction in these brain regions after training. These results suggest that individual differences in IC abilities modulate the neural plasticity of IC, and IC training specifically enhanced neural efficiency in individuals with low-IC abilities. Our findings provide a novel perspective for investigating the functional neuroplasticity of the IC system by highlighting the interaction between individual variances in IC abilities and short-term training effects.


Assuntos
Encéfalo/fisiologia , Plasticidade Neuronal/fisiologia , Transmissão Sináptica/fisiologia , Adulto , Função Executiva/fisiologia , Feminino , Humanos , Individualidade , Imageamento por Ressonância Magnética/métodos , Masculino , Desempenho Psicomotor/fisiologia , Adulto Jovem
18.
World J Gastroenterol ; 14(27): 4365-9, 2008 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-18666327

RESUMO

AIM: To study and determine the resting energy expenditure (REE) and oxidation rates of glucose, fat and protein in severe chronic hepatitis B patients. METHODS: A total of 100 patients with liver diseases were categorized into three groups: 16 in the acute hepatitis group, 56 in the severe chronic hepatitis group, and 28 in the cirrhosis group. The REE and the oxidation rates of glucose, fat and protein were assessed by indirect heat measurement using the CCM-D nutritive metabolic investigation system. RESULTS: The REE of the severe chronic hepatitis group (20.7 +/- 6.1 kcal/d per kg) was significantly lower than that of the acute hepatitis group (P = 0.014). The respiratory quotient (RQ) of the severe chronic hepatitis group (0.84 +/- 0.06) was significantly lower than that of the acute hepatitis and cirrhosis groups (P = 0.001). The glucose oxidation rate of the severe hepatitis group (39.2%) was significantly lower than that of the acute hepatitis group and the cirrhosis group (P < 0.05), while the fat oxidation rate (39.8%) in the severe hepatitis group was markedly higher than that of the other two groups (P < 0.05). With improvement of liver function, the glucose oxidation rate increased from 41.7% to 60.1%, while the fat oxidation rate decreased from 26.3% to 7.6%. CONCLUSION: The glucose oxidation rate is significantly decreased, and a high proportion of energy is provided by fat in severe chronic hepatitis. These results warrant a large clinical trail to assess the optimal nutritive support therapy for patients with severe liver disease.


Assuntos
Metabolismo Energético , Gorduras/metabolismo , Glucose/metabolismo , Hepatite B Crônica/metabolismo , Hepatopatias/metabolismo , Oxigênio/metabolismo , Proteínas/metabolismo , Adulto , Progressão da Doença , Feminino , Hepatite B Crônica/virologia , Humanos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Modelos Biológicos
19.
Cogn Sci ; 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29802646

RESUMO

In their paper "Do Bilinguals Automatically Activate Their Native Language When They Are Not Using it?", Costa, Pannunzi, Deco, and Pickering (Cognitive Science, 2017) proposed a reinterpretation of Thierry and Wu's (2004, 2007) finding of native language-based (Chinese, L1) ERP effects when they tested Chinese-English late bilinguals exclusively in their second language (English, L2). Using simulations in a six-node Hebbian learning model (three L1 nodes, three L2 nodes), Costa et al. suggested that form overlaps in L1 between otherwise unrelated words create a persistent relationship between their L2 translations. In this scenario, words in the nascent L2 lexicon overlapping in their L1 translations would become linked during learning because of the form overlap in L1; once the L2 words are learned, the direct link between them would be sufficient to generate robust, apparently "L1-mediated" priming without requiring any activation of L1 translations. Costa et al. contend that links between L2 words remain beyond the learning phase, even after links to L1 representations have been severed, and thus that their model affords an alternative account to (but not a rebuttal of) Thierry and Wu's claim of language non-selective activation-or automatic activation of translation equivalents-in late bilinguals. In this response, we build on Costa et al.'s original simulation code, showing that it can only reproduce L1-independent priming when implementing the L1 disconnection in their particular way. By contrast, when severing inter-language connections bidirectionally, their model fails to retain any sizeable influence of L1 form overlap on L2 activations. The model is not the theory, however, and we discuss several issues that would need to be addressed in further attempts to model language non-selective activation in late bilinguals.

20.
Front Psychol ; 9: 395, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29636713

RESUMO

The present functional magnetic resonance imaging (fMRI) study investigated influences of language contexts on inhibitory control and the underlying neural processes. Thirty Cantonese-Mandarin-English trilingual speakers, who were highly proficient in Cantonese (L1) and Mandarin (L2), and moderately proficient in English (L3), performed a picture-naming task in three dual-language contexts (L1-L2, L2-L3, and L1-L3). After each of the three naming tasks, participants performed a flanker task, measuring contextual effects on the inhibitory control system. Behavioral results showed a typical flanker effect in the L2-L3 and L1-L3 condition, but not in the L1-L2 condition, which indicates contextual facilitation on inhibitory control performance by the L1-L2 context. Whole brain analysis of the fMRI data acquired during the flanker tasks showed more neural activations in the right prefrontal cortex and subcortical areas in the L2-L3 and L1-L3 condition on one hand as compared to the L1-L2 condition on the other hand, suggesting greater involvement of the cognitive control areas when participants were performing the flanker task in L2-L3 and L1-L3 contexts. Effective connectivity analyses displayed a cortical-subcortical-cerebellar circuitry for inhibitory control in the trilinguals. However, contrary to the right-lateralized network in the L1-L2 condition, functional networks for inhibitory control in the L2-L3 and L1-L3 condition are less integrated and more left-lateralized. These findings provide a novel perspective for investigating the interaction between bilingualism (multilingualism) and inhibitory control by demonstrating instant behavioral effects and neural plasticity as a function of changes in global language contexts.

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