语言对认知的影响—— 基于双语认知“优势效应”的分析

双语认知优势效应不仅在言语领域有所表现, 更主要的体现在以认知控制、注意选择、心理抑制能力为基础的非言语认知领域。影响该效应出现的因素是多方面的, 第二语言获得年龄和双语熟练程度是其中两个最为重要的因素。研究发现, 双语表征和产生机制是导致双语认知优势效应的语言学机制, 而以Broca语言区为核心的大脑前额叶则是其主要的神经基础。未来该领域的研究不仅要进一步关注双语认知优势效应产生的内在言语机制和神经基础, 还应当积极关注双语认知和个体情绪、人格发展的关系。     

语言转换对非熟练双语者不同认知控制成分的即时影响

语言转换情境是否影响非熟练双语者的认知控制存在争议。实验1和实验2分别采用不同的实验范式探讨语言转换对非熟练双语者的认知控制是否会有即时的影响, 以及对不同认知控制成分的影响是否会有不同。结果表明, 语言转换情境能够即时地促进反应抑制, 阻碍干扰抑制, 但对认知灵活性没有影响, 同时说明了反应抑制、干扰抑制和认知灵活性属于3种不同的认知成分, 其内在作用机制不同。此外, 研究结果还进一步说明了双语者的认知控制优势是双语者长期双语使用的结果, 为双语优势的内在机制提供了实验支持。     

双语经验对认知能力的影响

综合近年关于双语经验对认知影响的研究, 探讨双语经验对认知的积极和消极两方面的影响, 且着重介绍了双语经验对认知的积极影响。双语经验对认知的积极影响主要体现在语言认知能力、非语言认知能力和中央执行功能几个方面。此外, 进一步对双语促进认知发展的原因进行了两方面的分析：一个是双语思维经验促进抑制控制的发展, 另一个双语学习经验强化双语者的左右脑交流, 从而导致脑功能活动方式的变化。最后, 对今后双语与认知关系的研究中需要注意的问题提出了一些思考。     

第二语言水平对双语者语言抑制能力的影响——来自英语–汉语单通道双语者和英语–美国手语双通道双语者的证据

采用同形异义词干扰任务考察第二语言水平对英语–汉语单通道双语者和英语–美国手语双通道双语者语言抑制能力的影响。结果发现:(1)高水平英语–汉语单通道双语者的语言抑制能力较强,但低水平英语–汉语单通道双语者与英语单语者的语言抑制能力没有显著差异,说明少量的双语经验不足以导致双语认知优势;(2)不同水平的英语–美国手语双通道双语者的语言抑制能力差异不显著。所以如此,与英语–美国手语双通道双语者不存在口语和手语的双语表征加工竞争有关。整个研究表明,双语认知优势效应与双语者的二语水平以及通道经验有关。     

执行控制的双语优势效应及其调节变量：来自元分析的证据

双语经验所带来的执行控制优势一直以来备受关注,然而对于双语优势效应的理论解释和具体表现则莫衷一是。为进一步明确执行控制双语优势效应的内在机制,当前研究区分了干扰抑制和反应抑制,并纳入年龄和语系类型等调节变量,最终通过对102篇文献进行元分析发现,执行控制整体的双语优势边缘显著(g=0.11),但在控制发表偏差之后双语优势消失。其中,干扰抑制成分的双语优势边缘显著(g=0.08);控制发表偏差后反应抑制成分的双语优势消失;认知灵活性成分的双语优势受到被试年龄和出版年份的调节。研究结果启示未来研究可更多关注干扰抑制和反应抑制在双语优势效应上的差异及其内在机制,以及双语者年龄和第二语言与母语间的语言距离对于执行控制双语优势的影响。     

第二语言学习与脑可塑性

脑可塑性指人脑会因为环境刺激、认知需求和行为经验而产生功能或结构改变。近10年来的单双语者对比和语言训练研究结果表明, 不论儿童、青年或老年人, 第二语言学习和使用都能改变其脑运行模式并带来相应结构变化, 包括灰质(GM)体积和白质(WM)密度增加, 且长期持续的双语经验还能形成认知优势, 帮助抵制由老化导致的负面认知影响。基于脑可塑性概念及其研究证据, 从双语经验与语言训练两方面, 对比分析了长期和短期第二语言学习引起脑功能或结构变化及其内在机制, 并对未来相关研究进行了展望。     

双语水平与认知控制心智转换

研究考察双语水平对认知控制心智转换的影响。通过语言转换和任务转换实验,比较两组一语水平相同而二语水平不同的“不平衡”中英双语者（40人,平均年龄20.30岁）。结果发现高水平组在语言转换中优于低水平组,但在任务转换中两组无显著差异。说明双语水平对认知控制心智转换的影响不显著。回归分析结果表明心智转换与双语水平无关,但二语使用显著预测任务转换代价,双语转换频率显著预测任务混合代价。研究表明双语水平对认知控制心智转换的促进作用不显著,但二语使用和双语转换频率可能是双语者心智转换能力增强的重要因素。研究进一步推进了双语促进认知控制的理论,明确了双语优势的具体来源及认知控制受影响的具体层面。     

国外双语口吃研究进展

双语口吃是双语者中出现的一种言语流畅性障碍。虽然双语教育越来越普及,但人们对双语口吃的关注却比较少。本文系统回顾了国外双语口吃方面的文献,主要发现:(1)口吃在双语者中比在单语者中更加流行;(2)影响双语口吃的因素包括双语的介入、缺乏经济安全和情绪不稳定、语言的相似性、第二语言获得的年龄等;(3)双语口吃的诊断需要参考一些附加诊断标准和方法,如伴随不流畅的次要行为(眨眼、身体运动等)、情感和认知评定、家族口吃史等;(4)双语口吃的治疗方法主要包括延缓或暂时取消双语教育;通过另一种语言的经验来战胜口吃;在不得不进行双语教育的情况下,应首先从孩子的优势语言入手进行口吃矫治。     

统计学习与双语认知的关系

统计学习是提取环境输入潜在规则的一种认知机制,其与语言的关联已得到证实。双语认知是学界关注的热点之一。统计学习与双语认知的关系如何?文章先介绍统计学习认知机制及其与语言的关系,然后从“统计学习能力可否预测二语学习表现”、“统计学习训练能否促进二语学习”和“双语经验能否提高统计学习能力”三个维度述评相关文献,并指出未来可从输入特征、个体差异和神经科学角度进一步探讨统计学习与双语认知的关系。     

双语者代码切换的认知与神经机制——从行为研究到脑成像研究

双语者代码切换的机制已引起心理语言学家和认知神经科学家的广泛关注。研究分别在行为层面和神经机制层面展开。发现,双语者在进行代码切换时会出现切换代价,切换代价来源于心理词典外部的语言任务图式之间的竞争,其机制可能与中央执行控制机制有密切联系,左侧额下回、双侧缘上回和背外侧前额叶等脑区参与了双语者的代码切换过程。文章还分析了在这一领域仍待研究的一些问题,并提出了进一步开展双语代码切换研究的建议。     

Bilingual enhancements have no socioeconomic boundaries

To understand how socioeconomic status (SES) and bilingualism simultaneously operate on cognitive and sensory function, we examined executive control, language skills, and neural processing of sound in adolescents who differed in language experience (i.e. English monolingual or Spanish‐English bilingual) and level of maternal education (a proxy for SES). We hypothesized that experience communicating in two languages provides an enriched linguistic environment that can bolster neural precision in subcortical auditory processing which, in turn, enhances cognitive and linguistic function, regardless of the adolescent's socioeconomic standing. Consistent with this, we report that adolescent bilinguals of both low and high SES demonstrate more stable neural responses, stronger phonemic decoding skills, and heightened executive control, relative to their monolingual peers. These results support the argument that bilingualism can bolster cognitive and neural function in low‐SES children and suggest that strengthened neural response consistency provides a biological mechanism through which these enhancements occur.     

Enhanced music sensitivity in 9-month-old bilingual infants

This study explores the influence of bilingualism on the cognitive processing of language and music. Specifically, we investigate how infants learning a non-tone language perceive linguistic and musical pitch and how bilingualism affects cross-domain pitch perception. Dutch monolingual and bilingual infants of 8–9 months participated in the study. All infants had Dutch as one of the first languages. The other first languages, varying among bilingual families, were not tone or pitch accent languages. In two experiments, infants were tested on the discrimination of a lexical (N = 42) or a violin (N = 48) pitch contrast via a visual habituation paradigm. The two contrasts shared identical pitch contours but differed in timbre. Non-tone language learning infants did not discriminate the lexical contrast regardless of their ambient language environment. When perceiving the violin contrast, bilingual but not monolingual infants demonstrated robust discrimination. We attribute bilingual infants’ heightened sensitivity in the musical domain to the enhanced acoustic sensitivity stemming from a bilingual environment. The distinct perceptual patterns between language and music and the influence of acoustic salience on perception suggest processing diversion and association in the first year of life. Results indicate that the perception of music may entail both shared neural network with language processing, and unique neural network that is distinct from other cognitive functions.     

Effects of Bilingual Language Use and Language Proficiency on 24-month-olds’ Cognitive Control

ABSTRACT

Although a bilingual advantage has been reported for various measures of cognitive control, most previous studies have looked at a limited range of cognitive control measures. Furthermore, they typically leave unaddressed whether positive effects of bilingualism hold for all bilinguals or whether these are modulated by differences in bilingual language use and proficiency of children and their parents. This study reports on tasks of selective attention and inhibitory control from 24-month-old bilinguals (n = 37) and monolinguals (n = 58). Their parents completed a Dutch vocabulary checklist assessing receptive and productive vocabulary as well as questionnaires on children’s attentional focusing, attention shifting and inhibitory control, and language background. Linear mixed-effect regressions showed no differences on cognitive control between the monolinguals and bilingual groups. However, analyses taking into account differences in children’s bilingual language use and proficiency and of their parents revealed a more nuanced picture. Specifically, children’s degree of balanced language usage predicted parent-rated cognitive control. Furthermore, bilingual toddlers who had parents were low proficient in one of the home languages showed significantly better performance on a selective attention task than toddlers whose parents were both proficient in both home languages. These findings suggest that both children’s active usage of two languages and their experience with switching depending on their interlocutor are related to cognitive control performance in young bilingual children. As such, they add to a growing body of evidence that the bilingual advantage in cognitive control is tied to specific conditions of bilingualism, already at a young age.     

Convergent cortical representation of semantic processing in bilinguals

This study examined whether semantic processes in two languages (English and Spanish) are mediated by a common neural system in fluent bilinguals who acquired their second language years after acquiring their first language. Functional magnetic resonance imaging was performed while bilingual participants made semantic and nonsemantic decisions about words in Spanish and English. There was greater activation for semantic relative to nonsemantic decisions in left and right frontal regions, with greater left frontal activation. The locations of activations were similar for both languages, and no differences were found when semantic decisions for English and Spanish words were compared directly. These results demonstrate a shared frontal lobe system for semantic analysis of the languages and are consistent with cognitive research on bilingualism indicating that the two languages of a bilingual person access a common semantic system.     

The role of componential analysis,categorical hypothesising,replicability and confirmation bias in testing for bilingual advantages in executive functioning

Kroll and Bialystok assert that managing two languages leads to a reorganisation of the neural circuits involved in language and cognitive processing and to bilingual advantages in executive functioning. This commentary documents that bilingual advantages in inhibitory control, switching and monitoring are difficult to replicate. Kroll and Bialystok argue that the use of componential analyses and categorical hypothesising are often responsible for the null results and that these research practices have created a false controversy surrounding the existence of bilingual advantages. An alternative perspective is presented suggesting that the appearance of a steady stream of published reports has been exaggerated because of the frequent use of risky small n's, a confirmation bias to report positive findings and a reluctance to conduct and report exact replications.     

双语(或多语)是否有利抵御老年痴呆症？

近50年来的语言神经科学研究确认了双(多)语经验的认知效应。就10年来双(多)语经验抵御老年痴呆症(特别是阿尔茨海默症, AD)的研究成果进行了深入探讨, 并基于认知储备(cognitive reserve)理论, 从功能和结构两方面探讨了双语(多语)经验抵御AD的神经机制。从外语的类型、熟悉程度、开始习得年龄, 以及研究方法等角度提出了要解决的问题, 旨在推动外语学习和教学, 并为老年化疾病和跨学科语言学研究提供新的思路。     

Brain network interactions in auditory, visual and linguistic processing

In the paper, we discuss the importance of network interactions between brain regions in mediating performance of sensorimotor and cognitive tasks, including those associated with language processing. Functional neuroimaging, especially PET and fMRI, provide data that are obtained essentially simultaneously from much of the brain, and thus are ideal for enabling one to assess interregional functional interactions. Two ways to use these types of data to assess network interactions are presented. First, using PET, we demonstrate that anterior and posterior perisylvian language areas have stronger functional connectivity during spontaneous narrative production than during other less linguistically demanding production tasks. Second, we show how one can use large-scale neural network modeling to relate neural activity to the hemodynamically-based data generated by fMRI and PET. We review two versions of a model of object processing - one for visual and one for auditory objects. The regions comprising the models include primary and secondary sensory cortex, association cortex in the temporal lobe, and prefrontal cortex. Each model incorporates specific assumptions about how neurons in each of these areas function, and how neurons in the different areas are interconnected with each other. Each model is able to perform a delayed match-to-sample task for simple objects (simple shapes for the visual model; tonal contours for the auditory model). We find that the simulated electrical activities in each region are similar to those observed in nonhuman primates performing analogous tasks, and the absolute values of the simulated integrated synaptic activity in each brain region match human fMRI/PET data. Thus, this type of modeling provides a way to understand the neural bases for the sensorimotor and cognitive tasks of interest.