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Computational morphometry of magnetic resonance images represents a powerful tool for studying macroscopic differences in human brains. In the present study (N participants = 829), we combined different techniques and measures of brain morphology to investigate one of the most compelling topics in neuroscience: sexual dimorphism in human brain structure. When accounting for overall larger male brains, results showed limited sex differences in gray matter volume (GMV) and surface area. On the other hand, we found larger differences in cortical thickness, favoring both males and females, arguably as a result of region-specific differences. We also observed higher values of fractal dimension, a measure of cortical complexity, for males versus females across the four lobes. In addition, we applied source-based morphometry, an alternative method for measuring GMV based on the independent component analysis. Analyses on independent components revealed higher GMV in fronto-parietal regions, thalamus and caudate nucleus for females, and in cerebellar- temporal cortices and putamen for males, a pattern that is largely consistent with previous findings.

In the present meta-analysis, we investigated the robustness and the magnitude of the Foreign Language Effect (FLE)-that is, the putative effect of language context (native versus foreign language) on decision-making. We also investigated whether the FLE is moderated by language experience-measured by second language age of acquisition and proficiency-or by methodological choices-the types of decision problems adopted, the presentation modality of the tasks administered, and the perspective in which problems are framed. Our results showed a reliable FLE, which was not moderated by language experience or methodological choices. We discuss our findings in relation to available theories of FLE, and indicate possible future directions to improve our understanding of the interplay between bilingualism and decision-making.

Inhibitory control is the capacity to withhold or suppress a thought or action intentionally. The anterior Midcingulate Cortex (aMCC) participates in response inhibition, a proxy measure of inhibitory control. Recent research suggests that response inhibition is modulated by individual variability in the aMCC sulcal morphology. However, no study has investigated if this phenomenon is associated with neurofunctional differences during a task. In this study, 42 participants performed an Attention Network Task and a Numerical Stroop task in an MRI scanner. We investigated differences in brain activity and response inhibition efficiency between individuals with symmetric and asymmetric aMCC sulcal patterns. The results showed that aMCC morphological variability is partly associated with inhibitory control, and revealed greater activation in individuals with symmetric patterns during the Stroop task. Our findings provide novel insights into the functional correlates of the relationship between aMCC morphology and executive abilities.

Bilingualism is a natural laboratory for studying whether the brain's structural connectome is influenced by different aspects of language experience. However, evidence on how distinct components of bilingual experience may contribute to structural brain adaptations is mixed. The lack of consistency, however, may depend, at least in part, on methodological choices in data acquisition and processing. Herein, we adopted the Network Neuroscience framework to investigate how individual differences in second language (L2) exposure, proficiency, and age of acquisition (AoA) – measured as continuous between-subject variables – relate to whole-brain structural organization. We observed that L2 exposure modulated the connectivity of two networks of regions subserving language comprehension and production. L2 proficiency was associated with enhanced connectivity within a rostro-caudal network, which supports language selection and word learning. Moreover, L2 AoA and exposure affected inter-hemispheric communication between control-related regions. These findings expand mechanistic knowledge about particular environmental factors associated with specific variation in brain structure.

Notwithstanding rising interest, a coherent picture of the brain's representation of two languages has not yet been achieved. In the present meta-analysis we analysed a large number of functional neuroimaging studies focusing on language processing in bilinguals. We used activation likelihood estimation (ALE) to enucleate activation areas involved in bilingual processing and control of different types of linguistic knowledge – lexico-semantics, grammar, phonology – in L1 and L2. Results show that surprisingly, compared to L2, lexico-semantic processing in L1 involves a widespread system of cortico-subcortical regions, especially when L2 is acquired later in life. By contrast, L2 processing recruits regions exceeding the L1 semantic network and relating to executive control processes. Only few regions displayed selective activation for grammar and phonology. Analyses of language switching highlight a functional overlap between domain-general and bilingual language control networks. Collectively, our findings point to a shared neural network for L1 and L2 with few differences depending on the linguistic level. The emerging picture identifies under-investigated issues, offering clear directions for future research.

There is currently no agreement on which factor modulates most effectively and enduringly brain plasticity in bilingual individuals. Grouping heterogeneous linguistic profiles under a dichotomous condition (bilingualism versus monolingualism) may obscure critical aspects of language experience underlying neural changes, thus leading to variable and often conflicting findings. In the present study, we overcome these limitations by analyzing the individual and joint contribution of L2 AoA, proficiency and usage – all measured as continuous variables – on the resting-state functional connectivity of the brain networks mediating the specific demands of bilingual language processing: the language network and the executive control network. Our results indicate that bilingual experience – defined as a continuous and multifaceted phenomenon – impacts brain plasticity by modulating the functional connectivity both within and between language and control networks. Each experience-related factor considered played a role in changing the connectivity of these regions. Moreover, the effect of AoA was modulated by proficiency and usage. These findings shed new light on the importance of modeling bilingualism as a gradient measure rather than an all-or-none phenomenon.

Learning and learning to regulate more than one language is shown to have an impact on the structural connectivity of the brain in networks related to language processing and executive control. The available evidence remains however variable in terms of the occurrence, localization and extent of these effects. Variability likely depends on the fact that grouping heterogeneous linguistic profiles under a dichotomous condition (bilingualism vs. monolingualism) may obscure critical aspects of language experience underlying white matter changes. Here, we treated the main quantifiable features in which bilingual experience can be partitioned—that is, age of acquisition, proficiency and use of a second language—as continuous variables, and tested their effects on a sample of young adult participants. Findings indicate that the time spent using a second language, rather than the age of acquisition or knowledge of that language, significantly modulates white matter microstructure in a bilateral cingulo-frontal cluster encompassing structures primarily related to language control. Taken together, these data point to a usage-dependent remodeling of cingulo-frontal connections, and substantiate the conceptualization of bilingualism as a complex and dynamic experience.

The moral foreign language effect (MFLE) describes how people's decisions may change when a moral dilemma is presented in either their native (NL) or foreign language (FL). Growing attention is being directed to unpacking what aspects of bilingualism may influence the MFLE, though with mixed or inconclusive results. The current study aims to bridge this gap by adopting a conceptualization of bilingualism that frames this construct as a composite and continuous measure. In a between-group analysis, we asked 196 Italian-English bilinguals to perform a moral dilemmas task in either their NL (i.e., Italian) or FL (i.e., English). In a within-group analysis, we evaluated the effects of FL age of acquisition, FL proficiency, and language dominance - all measured as continuous variables - on moral decision-making. Overall, findings indicate that differences within bilinguals' language experience impact moral decisions in an FL. However, the effect of the linguistic factors considered was not ubiquitous across dilemmas, and not always emerged into a MFLE. In light of these results, our study addresses the importance of treating bilingualism as multidimensional, rather than a unitary variable. It also discusses the need to reconceptualize the FLE and its implications on moral decision-making.

Neuroimaging evidence suggests that bilingualism may act as a source of neural plasticity. However, prior work has mostly focused on bilingualism-induced alterations in gray matter volume and white matter tract microstructure, with additional effects related to other neurostructural indices that might have remained undetected. The degree of cortical folding or gyrification is a morphometric parameter which provides information about changes on the brain's surface during development, aging and disease. We used Surface-based Morphometry (SBM) to investigate the contribution of bilingual experience to gyrification from early adulthood to old age in a sample of bilinguals and monolingual controls. Despite widespread cortical folding reductions for all participants with increasing age, preserved gyrification exclusive to bilinguals was detected in the right cingulate and entorhinal cortices, regions vulnerable with normal and pathological brain aging. Our results provide novel insights on experience-related cortical reshaping and bilingualism-induced cortical plasticity in adulthood.

For everyday communication, bilingual speakers need to face the complex task of rapidly choosing the most appropriate language given the context, maintaining this choice over the current communicative act, and shielding lexical selection from competing alternatives from non-target languages. Yet, speech production of bilinguals is typically flawless and fluent. Most of the studies available to date constrain speakers' language choice by cueing the target language and conflate language choice with language use. This left largely unexplored the neural mechanisms underlying free language choice, i.e., the voluntary situation of choosing the language to speak. In this study, we used fMRI and Multivariate Pattern Analysis to identify brain regions encoding the target language when bilinguals are free to choose in which language to name pictures. We found that the medial prefrontal cortex encoded the chosen language prior to speaking. By contrast, during language use, language control recruited a wider brain network including the left inferior frontal lobe, the basal ganglia, and the angular and inferior parietal gyrus bilaterally. None of these regions were involved in language choice. We argue that the control processes involved in language choice are different from those involved in language use. Furthermore, our findings confirm that the medial prefrontal cortex is a domain-general region critical for free choice and that bilingual language choice relies on domain general processes.

In this work, we present ITABÙ, a database containing ratings for taboo words in Italian on emotional dimensions - valence, arousal, and dominance - and semantic dimensions - imageability, familiarity, and concreteness. Data have been collected from 130 participants by means of online questionnaires. Emotional dimensions are also analyzed in relation to participants' gender. In addition to providing a detailed emotional and semantic characterization of stimuli, ITABÙ is an essential tool for psycholinguistic and neurolinguistic research with taboo words.

Bilingualism represents a distinctive way to investigate the interplay between brain and behaviour, and an elegant model to study the role of environmental factors in shaping this relationship. Past neuroimaging research has mainly focused on how bilingualism influences brain structure, and how eventually the brain accommodates a second language. In this paper, we discuss a more recent contribution to the field which views bilingualism as lens to understand brain-behaviour mappings from a different perspective. It has been shown, in contexts not related to bilingualism, that cognitive performance across several domains can be predicted by neuroanatomical variants determined prenatally and largely impervious to postnatal changes. Here, we discuss novel findings indicating that bilingualism modulates the predictive role of these variants on domain-specific cognition. The repercussions of these findings are potentially far-reaching on multiple levels, and highlight the need to shape more complex questions for progress in cognitive neuroscience approaches to bilingualism.

Background: The dorsal anterior cingulate cortex (dACC) is a key network hub for cognitive control and environmental adaptation. Previous studies have shown that task-based functional activity in this area is constrained by individual differences in sulcal pattern, a morphologic feature of cortex anatomy determined during fetal life and stable throughout development. Methods: By using anatomical magnetic resonance imaging and seed-based resting-state functional connectivity (rsFC), we explored the influence of sulcal pattern variability on the functional architecture of the dACC in a sample of healthy adults aged 20-80 years (n = 173). Results: Overall, rsFC was associated with individual differences in sulcal pattern. Furthermore, rsFC was modulated by the age-sulcal pattern interaction. Conclusion: Our results suggest a relationship between brain structure and function that partly traces back to early stages of brain development. The modulation of rsFC by the age-sulcal pattern interaction indicates that the effects of sulcal pattern variability on the functional architecture of the dACC may change over adulthood, with potential repercussions for brain network efficiency and cognitive function in aging.

The anterior cingulate cortex (ACC) is a key structure implicated in the regulation of cognitive control (CC). Previous studies suggest that variability in the ACC sulcal pattern—a neurodevelopmental marker unaffected by maturation or plasticity after birth—is associated with intersubject differences in CC performance. Here, we investigated whether bilingual experience modulates the effects of ACC sulcal variability on CC performance across the lifespan. Using structural MRI, we first established the distribution of the ACC sulcal patterns in a large sample of healthy individuals (N = 270) differing on gender and ethnicity. Second, a participants’ subsample (N = 157) was selected to test whether CC performance was differentially affected by ACC sulcation in bilinguals and monolinguals across age. A prevalent leftward asymmetry unaffected by gender or ethnicity was reported. Sulcal variability in the ACC predicted CC performance differently in bilinguals and monolinguals, with a reversed pattern of structure–function relationship: asymmetrical versus symmetrical ACC sulcal patterns were associated with a performance advantage in monolinguals and a performance detriment to bilinguals and vice versa. Altogether, these findings provide novel insights on the dynamic interplay between early neurodevelopment, environmental background and cognitive efficiency across age.

The use of socially opprobrious words (taboo words) is a cross-cultural phenomenon occurring between individuals from almost all social extractions. The neurocognitive correlates of using taboo words in the native language (L1) as compared to their use in a second (L2) language are largely unknown. We used fMRI to investigate the processing of taboo and non-taboo stimuli in monolinguals (Experiment 1) and highly proficient bilinguals (Experiment 2) engaged in lexical decision tasks. We report that for L1 socio-pragmatic knowledge is automatically conveyed and taboo words are processed with less effort than non-taboo words. For L2 the processing of taboo words is more effortful and engages additional structures (anterior cingulate cortex, insula) involved in social-norm representation and evaluation. Our results contribute to understand the interface between language and social-norm processing indicating that lexical processing is affected by socio-pragmatic knowledge, but only when the speaker has a contextual use of the language.

Anorexia Nervosa (AN) is a disorder with a dramatic impact on both the individual and society. Besides severe weight loss, excessive physical exercise and cognitive disturbances can be present in patients with AN as primary symptoms of the pathology or as secondary effects induced by physical and metabolic alterations. Mechanistic research in this field has taken advantage of a well characterized animal model, the activity-based anorexia model (ABA). ABA rodents and subjects with AN show clear behavioral and physiological similarities, but a throughout neurocognitive assessment of the model is still missing. Here, we review the available literature in the ABA field, highlighting similarities between ABA and AN at the behavioral, neurophysiological and cognitive level. Furthermore, based on availability, feasibility and adaptability of rodent behavioral protocols, we propose a set of neurocognitive assays that can be performed on the ABA. The proposed assessment represents an important step forward in the validation and extension of the ABA model, opening several routes of investigation related to AN and other eating disorders.

Evidence that bilingualism protects against age-related neurocognitive decline is mixed. One relatively consis- tent finding is that bilingual seniors have greater grey matter volume (GMV) in regions implicated in executive control (EC) and language processing. Here, we compare the neuroplastic effects of bilingual experience on the EC network of young and aging populations directly, and for the first time we evaluate the extent to which such effects may predict executive control performance across age. We used GMV as an index of neural reserve and response time (RT) performance on the Flanker task for measuring EC efficiency. In the presence of age-related widespread GM deterioration, bilinguals had greater GMV than monolinguals in key regions of interest across age. Moreover, whereas EC performance in monolingual seniors was strictly related to GMV, this was not ob- served for bilingual seniors or younger participants in either group. Interactions between expected effects-of-age and language group on the relationships between GMV and RT suggested that bilingualism affords differential benefits across the lifespan. In younger participants, greater GMV offered no behavioral benefit on EC perfor- mance, whilst it did for seniors. It thus appears that age-related cognitive decline following GMV loss in the EC network is delayed in bilinguals.

With event-related functional MRI (fMRI) and with behavioral measures we studied the brain processes underlying the acquisition of native language literacy. Adult dialect speakers were scanned while reading words belonging to three different conditions: dialect words, i.e., the native language in which subjects are illiterate (dialect), German words, i.e., the second language in which subjects are literate, and pseudowords. Investigating literacy acquisition of a dialect may reveal how novel readers of a language build an orthographic lexicon, i.e., establish a link between already available semantic and phonological representations and new orthographic word forms. The main results of the study indicate that a set of regions, including the left anterior hippocampal formation and subcortical nuclei, is involved in the buildup of orthographic representations. The repeated exposure to written dialect words resulted in a convergence of the neural substrate to that of the language in which these subjects were already proficient readers. The latter result is compatible with a "fast" brain plasticity process that may be related to a shift of reading strategies.

Bilinguals require a high degree of cognitive control to select the language intended for speaking and inhibit the unintended. Previous neuroimaging studies have not teased apart brain regions for generating the intention to use a given language, and those for speaking in that language. Separating these two phases can clarify at what stage competition between languages occurs. In this fMRI study German-English bilinguals were first cued to use German or English. After a delay, they named a picture in the cued language. During the intention phase, the precuneus, right superior lateral parietal lobule, and middle temporal gyrus were more activated when participants had to update the currently active language. During language execution activation was higher for English compared to German in brain areas associated with cognitive control, most notably the anterior cingulate and the caudate. Our results suggest two different systems enabling cognitive control during bilingual language production.

Item does not contain fulltext, The impacts of bilingualism upon the human brain, specifically in terms of the neuroplastic and neurofunctional changes upon general cognitive functions and on cognitive decline, are currently attracting much attention not only from the neuroscience and psycholinguistic communities but also from the general public. Researchers are especially focused on the putative protective effects of bilingualism upon cognitive decline.

Neuroimaging studies suggest that the neural network involved in language control may not be specific to bi-/multilingualism but is part of a domain-general executive control system. We report a trilingual case of a Cantonese (L1), English (L2), and Mandarin (L3) speaker, Dr. T, who sustained a brain injury at the age of 77 causing lesions in the left frontal lobe and in the left temporo-parietal areas resulting in fluent aphasia. Dr. T's executive functions were impaired according to a modified version of the Stroop color-word test and the Wisconsin Card Sorting Test performance was characterized by frequent perseveration errors. Dr. T demonstrated pathological language switching and mixing across her three languages. Code switching in Cantonese was more prominent in discourse production than confrontation naming. Our case suggests that voluntary control of spoken word production in trilingual speakers shares neural substrata in the frontobasal ganglia system with domain-general executive control mechanisms. One prediction is that lesions to such a system would give rise to both pathological switching and impairments of executive functions in trilingual speakers.

In a world that is becoming more multilingual, bilingual aphasia is a clinical problem with a major clinical impact. However, at present we lack causal explanations of the many features of recovery patterns and there is no consensus about the language in which the patient should receive speech therapy. Further advance requires an understanding of the dynamics of recovery. In a novel longitudinal, single-case study, we combine fMRI and dynamic causal modeling to examine the effects of specific language treatment for picture naming on the representation and control of language areas during the course of recovery. Improved performance in the treated language was associated with increased activation in language areas. Consistent with theoretical expectations, causal modeling indicated increased connectedness of the control and language networks for the treated language. This functional approach holds great promise for investigating recovery patterns and the effects of specific language treatment in bilingual aphasic patients.

Dual-route models of graphemic word processing have become paradigm cases for cognitive science and have been very successful in accounting for word and nonword reading and writing and their impairments. Although they were originally based on English, research has meanwhile been conducted on other languages and orthographies. Data are now available on several other European languages based on alphabetic scripts (French, German, and Italian), consonantal scripts (Hebrew), syllabic scripts (Japanese kana), and ideographic scripts (Chinese and Japanese kanji). Taken together, these studies point to the universality of two routes for reading, a lexical and a sublexical one, applying to nonalphabetic as well as alphabetic languages, and each route can be selectively impaired, thus suggesting their independent neural organization (Butterworth & Yin, 1991; Weekes, 2005). At the same time, neuroimaging studies of subjects in different alphabetic languages with a different degree of transparency between graphemes and phonemes suggest that a greater reliance on one or the other route depends on language-specific features (Paulesu et al., 2001). Given the similarity between languages with respect to the architecture of the model, future research can now focus on the role of specific differences.

The present fMRI study of semantic fluency for animal and tool names provides further evidence for category-specific brain activations, and reports task-related changes in effective connectivity among defined cerebral regions. Two partially segregated systems of functional integration were highlighted: the tool condition was associated with an enhancement of connectivity within left hemispheric regions, including the inferior prefrontal and premotor cortex, the inferior parietal lobule and the temporo-occipital junction; the animal condition was associated with greater coupling among left visual associative regions. These category-specific functional differences extend the evidence for anatomical specialization to lexical search tasks, and provide for the first time evidence of category-specific patterns of functional integration in word-retrieval.