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Bilingual experience can delay cognitive decline during aging. A general hypothesis is that the executive control system of bilinguals faces an increased load due to controlling two languages, and this increased load results in a more “tuned brain” that eventually creates a neural reserve. Here we explored whether such a neuroprotective effect is independent of language modality, i.e., not limited to bilinguals who speak two languages but also occurs for bilinguals who use a spoken and a signed language. We addressed this issue by comparing bimodal bilinguals to monolinguals in order to detect age-induced structural brain changes and to determine whether we can detect the same beneficial effects on brain structure, in terms of preservation of gray matter volume (GMV), for bimodal bilinguals as has been reported for unimodal bilinguals. Our GMV analyses revealed a significant interaction effect of age × group in the bilateral anterior temporal lobes, left hippocampus/amygdala, and left insula where bimodal bilinguals showed slight GMV increases while monolinguals showed significant age-induced GMV decreases. We further found through cortical surface-based measurements that this effect was present for surface area and not for cortical thickness. Moreover, to further explore the hypothesis that overall bilingualism provides neuroprotection, we carried out a direct comparison of GMV, extracted from the brain regions reported above, between bimodal bilinguals, unimodal bilinguals, and monolinguals. Bilinguals, regardless of language modality, exhibited higher GMV compared to monolinguals. This finding highlights the general beneficial effects provided by experience handling two language systems, whether signed or spoken. Hum Brain Mapp 38:4109–4124, 2017. © 2017 Wiley Periodicals, Inc.

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.

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.

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.

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.

This paper investigates the production of Persian–English bilingual compound verbs (BCVs) of the type [VERB+VERB]. In this type of code-switched structure, a lexical verb from the donor language English is combined with a light verb from the native language Persian. We tested the hypothesis that in Persian–English BCVs English verbs occupy the nominal slots of monolingual Persian complex predicates of the type [NOMINAL+VERB]. Two methodologies were used. A conversational-corpus analysis confirmed our predictions that Persian–English BCVs have translation-equivalent Persian compound verbs, that the English verbs denote the same action as the nominal constituents of those monolingual constructions, and that the support verbs tend to correspond in both types of compound verbs. A bilingual picture-word interference experiment provided evidence suggesting that English verbs interfere with the production of the nominal constituents of complex Persian verbs in Persian-bilingual speakers. We conclude that words from different word categories can compete for lexical access.

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.

Whether bilingualism acts positively against neurocognitive decline is intensely debated. Although some reasons for it might be ideological, variability in sampling procedures and experimental design represent potential sources of inconsistency among studies. In this paper, we contend that bilingualism renders the extra-years of life of an increasingly long-lived population cognitively healthy, but only under specific conditions such as continuous practice and immersion in bilingual environments. We thus disagree with some authors’ recommendation that bilingualism be removed from consideration as a neuroprotective factor. We suggest, at the same time, that bilingualism should not be treated as axiologically superior to other environmental measures that promise to contrast the progressive loss of functional independence with increasing age. We conclude by emphasizing the need to evaluate the protective effects of L2-learning on the aging brain in a multimodal intervention perspective, thereby dissociating the effects of bilingualism from those of other cognitively stimulating factors.

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.

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.

Objective: To evaluate the clinical characteristics and rehabilitation management of patients who undergo amputation for COVID-19-associated coagulopathy. Methods: Clinical and laboratory data for 3 patients were analysed and their rehabilitative management discussed. Results: The medical records of 3 patients who had undergone amputation due to acute lower extremity ischaemia and who were provided with rehabilitation in the COVID-19 unit at San Raffaele Scientific Insitute, Milan Italy were reviewed. Conclusion: Coagulation changes related to SARSCoV- 2 may complicate recovery from this devastating disease. The rehabilitation management of amputated patients for COVID-19 acute lower extremity ischaemia is based on a multilevel approach for clinical, functional, nutritional and neuropsychological needs. Based on this limited experience, a dedicated programme for this specific group of patients seems advantageous to warrant the best functional outcome and quality of life.

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.

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.

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.

Amnestic mild cognitive impairment (aMCI) is a clinical condition characterized by memory impairment in the absence of any other cognitive impairment and is commonly associated with high conversion to Alzheimer's disease. Recent evidence shows that executive functions and selective attention mechanisms could also be impaired in aMCI. In this study, we investigated performance differences (i.e., reaction times [RTs] and accuracy) between a group of aMCI participants and a group of age-matched healthy individuals on the attentional network task (ANT) focusing on situations with increased interference. In particular, we assessed the relationship between interference and conflict effects and grey matter volumes (GMVs) of the anterior cingulate cortex (ACC)/pre-supplementary motor area in the entire sample because of its crucial role in conflict monitoring. When compared with controls, aMCI participants were less accurate on the ANT, showing increased interference and conflict effects, but no differences in RTs. In addition, aMCI participants exhibited lower GMV in the ACC than controls. While better accuracy for interference and conflict effects was associated with an increase of GMV in the ACC for both groups, RTs from the interference effect were negatively correlated with GMV of the ACC only in aMCI participants. In other words, lower GMV values of the ACC were paralleled with significantly impaired performance in terms of interference resolution. In conclusion, our study suggests the presence of a selective impairment in interference and conflict monitoring in aMCI, which in turn is associated with decreased GMVs in the ACC.

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.

Research has shown that linguistic functions in the bilingual brain are subserved by similar neural circuits as in monolinguals, but with extra-activity associated with cognitive and attentional control. Although a role for the right cerebellum in multilingual language processing has recently been acknowledged, a potential role of the left cerebellum remains largely unexplored.This paper reports the clinical and fMRI findings in a strongly right-handed (late) multilingual patient who developed differential polyglot aphasia, ataxic dysarthria and a selective decrease in executive function due to an ischemic stroke in the left cerebellum. fMRI revealed that lexical-semantic retrieval in the unaffected L1 was predominantly associated with activations in the left cortical areas (left prefrontal area and left postcentral gyrus), while naming in two affected non-native languages recruited a significantly larger bilateral functional network, including the cerebellum. It is hypothesized that the left cerebellar insult resulted in decreased right prefrontal hemisphere functioning due to a loss of cerebellar impulses through the cerebello-cerebral pathways.

Language selection (or control) refers to the cognitive mechanism that controls which language to use at a given moment and context. It allows bilinguals to selectively communicate in one target language while minimizing the interferences from the nontarget language. Previous studies have suggested the participation in language control of different brain areas. However, the question remains whether the selection of one language among others relies on a language-specific neural module or general executive regions that also allow switching between different competing behavioral responses including the switching between various linguistic registers. In this functional magnetic resonance imaging study, we investigated the neural correlates of language selection processes in German-French bilingual subjects during picture naming in different monolingual and bilingual selection contexts. We show that naming in the first language in the bilingual context (compared with monolingual contexts) increased activation in the left caudate and anterior cingulate cortex. Furthermore, the activation of these areas is even more extended when the subjects are using a second weaker language. These findings show that language control processes engaged in contexts during which both languages must remain active recruit the left caudate and the anterior cingulate cortex (ACC) in a manner that can be distinguished from areas engaged in intralanguage task switching.

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.