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Brain clocks, which quantify discrepancies between brain age and chronological age, hold promise for understanding brain health and disease. However, the impact of diversity (including geographical, socioeconomic, sociodemographic, sex and neurodegeneration) on the brain-age gap is unknown. We analyzed datasets from 5,306 participants across 15 countries (7 Latin American and Caribbean countries (LAC) and 8 non-LAC countries). Based on higher-order interactions, we developed a brain-age gap deep learning architecture for functional magnetic resonance imaging (2,953) and electroencephalography (2,353). The datasets comprised healthy controls and individuals with mild cognitive impairment, Alzheimer disease and behavioral variant frontotemporal dementia. LAC models evidenced older brain ages (functional magnetic resonance imaging: mean directional error = 5.60, root mean square error (r.m.s.e.) = 11.91; electroencephalography: mean directional error = 5.34, r.m.s.e. = 9.82) associated with frontoposterior networks compared with non-LAC models. Structural socioeconomic inequality, pollution and health disparities were influential predictors of increased brain-age gaps, especially in LAC (R² = 0.37, F² = 0.59, r.m.s.e. = 6.9). An ascending brain-age gap from healthy controls to mild cognitive impairment to Alzheimer disease was found. In LAC, we observed larger brain-age gaps in females in control and Alzheimer disease groups compared with the respective males. The results were not explained by variations in signal quality, demographics or acquisition methods. These findings provide a quantitative framework capturing the diversity of accelerated brain aging.

The Action-sentence Compatibility Effect (ACE) is a well-known demonstration of the role of motor activity in the comprehension of language. Participants are asked to make sensibility judgments on sentences by producing movements toward the body or away from the body. The ACE is the finding that movements are faster when the direction of the movement (e.g., toward) matches the direction of the action in the to-be-judged sentence (e.g., Art gave you the pen describes action toward you). We report on a pre-registered, multi-lab replication of one version of the ACE. The results show that none of the 18 labs involved in the study observed a reliable ACE, and that the meta-analytic estimate of the size of the ACE was essentially zero.

IntroductionTimely diagnosis of behavioral variant frontotemporal dementia (bvFTD) remains challenging because it depends on clinical expertise and potentially ambiguous diagnostic guidelines. Recent recommendations highlight the role of multimodal neuroimaging and machine learning methods as complementary tools to address this problem.MethodsWe developed an automatic, cross-center, multimodal computational approach for robust classification of patients with bvFTD and healthy controls. We analyzed structural magnetic resonance imaging and resting-state functional connectivity from 44 patients with bvFTD and 60 healthy controls (across three imaging centers with different acquisition protocols) using a fully automated processing pipeline, including site normalization, native space feature extraction, and a random forest classifier.ResultsOur method successfully combined multimodal imaging information with high accuracy (91%), sensitivity (83.7%), and specificity (96.6%).DiscussionThis multimodal approach enhanced the system's performance and provided a clinically informative method for neuroimaging analysis. This underscores the relevance of combining multimodal imaging and machine learning as a gold standard for dementia diagnosis.

The overt pronoun constraint (OPC) states that, in null subject languages, overt pronoun subjects of embedded clauses cannot be bound by "wh-" or quantifier antecedents. Through the administration of two written questionnaires, we examined the OPC in 246 monolingual native speakers of three dialects of Spanish, spoken in Barranquilla (Colombia), Santiago (Chile), and Buenos Aires (Argentina). We tested separately the predictions that overt pronouns cannot be bound by "wh-" antecedents (Experiment 1) and that they cannot be bound by quantifier antecedents (Experiment 2). We found that the OPC was not operative in any of these dialects. In Experiment 1, the percentage of bound answers was approximately the same as the percentage of anaphoric answers. In Experiment 2, the percentage of bound answers was significantly higher than the percentage of anaphoric answers. Implications both for theories of pronoun resolution in null subject languages and for theories of first and second language acquisition are discussed.

Background: Fatigue ranks among the most common and disabling symptoms in multiple sclerosis (MS). Recent theoretical works have surmised that this trait might be related to alterations across interoceptive mechanisms. However, this hypothesis has not been empirically evaluated. Objectives: To determine whether fatigue in MS patients is associated with specific behavioral, structural, and functional disruptions of the interoceptive domain. Methods: Fatigue levels were established via the Modified Fatigue Impact Scale. Interoception was evaluated through a robust measure indexed by the heartbeat detection task. Structural and functional connectivity properties of key interoceptive hubs were tested by magnetic resonance imaging (MRI) and resting-state functional MRI. Machine learning analyses were employed to perform pairwise classifications. Results: Only patients with fatigue presented with decreased interoceptive accuracy alongside decreased gray matter volume and increased functional connectivity in core interoceptive regions, the insula, and the anterior cingulate cortex. Each of these alterations was positively associated with fatigue. Finally, machine-learning analysis with a combination of the above interoceptive indices (behavioral, structural, and functional) successfully discriminated (area under the curve > 90%) fatigued patients from both non-fatigued and healthy controls. Conclusion: This study offers unprecedented evidence suggesting that disruptions of neurocognitive markers subserving interoception may constitute a signature of fatigue in MS. [ABSTRACT FROM AUTHOR]

Despite the growth of research on translation and interpreting, measures of competence in such activities typically stem from informal, non-validated instruments. This scenario casts doubts on the ensuing findings and hinders comparability across studies. To address the issue, we introduce the Translation and Interpreting Competence Questionnaire (TICQ), an online tool for collecting relevant quantitative and qualitative data. The instrument comprises three sections. Section A covers demographic data and aspects of language history and multilingual abilities. Sections B and C focus on translation and interpreting competence, respectively, via self-rating scales on modality-specific skills and questions about procedural, declarative, and otherwise professional factors. A stringent validation procedure based on data from 284 participants (including item reliability estimations, principal component analyses, and multigroup discriminant function analyses) revealed that the TICQ can robustly classify subjects in terms of their actual status (laymen, students, professionals) in the translation and interpreting communities –with an accuracy of roughly 80%. Importantly, the TICQ is available in three languages, it is fully customizable, and it can be administered online, locally or in pen-and-paper format. Briefly, this user-friendly tool provides comprehensive information for empirical investigations in the field, offering unprecedented opportunities to enhance sample selection, between-study comparisons, and meta-analytic research. [ABSTRACT FROM AUTHOR]

Frontostriatal networks play critical roles in grounding action semantics and syntactic skills. Indeed, their atrophy distinctively disrupts both domains, as observed in patients with Huntington's disease (HD) and Parkinson's disease, even during early disease stages. However, frontostriatal degeneration in these conditions may begin up to 15 years before the onset of clinical symptoms, opening avenues for pre‐clinical detection via sensitive tasks. Such a mission is particularly critical in HD, given that patients’ children have 50% chances of inheriting the disease. Against this background, we assessed whether deficits in the above‐mentioned domains emerge in subjects at risk to develop HD. We administered tasks tapping action semantics, object semantics, and two forms of syntactic processing to 18 patients with HD, 19 asymptomatic first‐degree relatives, and sociodemographically matched controls for each group. The patients evinced significant deficits in all tasks, but only those in the two target domains were independent of overall cognitive state. More crucially, relative to controls, the asymptomatic relatives were selectively impaired in action semantics and in the more complex syntactic task, with both patterns emerging irrespective of the subjects’ overall cognitive state. Our findings highlight the relevance of these dysfunctions as potential prodromal biomarkers of HD. Moreover, they offer theoretical insights into the differential contributions of frontostriatal hubs to both domains while paving the way for innovations in diagnostic procedures. [ABSTRACT FROM AUTHOR]

Traditionally, Huntington's disease (HD) has been known as a movement disorder, characterized by motor, psychiatric, and cognitive impairments. Recent studies have shown that motor and action-language processes are neurally associated. The cognitive mechanisms underlying this interaction have been investigated through the action compatibility effect (ACE) paradigm, which induces a contextual coupling of ongoing motor actions and verbal processing. The present study is the first to use the ACE paradigm to evaluate action- word processing in HD patients (HDP) and their families. Specifically, we tested three groups: HDP, healthy first-degree relatives (HDR), and non-relative healthy controls. The results showed that ACE was abolished in HDP as well as HDR, but not in controls. Furthermore, we found that the processing deficits were primarily linguistic, given that they did not correlate executive function measurements. Our overall results underscore the role of cortico-basal ganglia circuits in action-word processing and indicate that the ACE task is a sensitive and robust early biomarker of HD and familial vulnerability. [ABSTRACT FROM AUTHOR]