Investigating White Matter Lesion Load, Intrinsic Functional Connectivity, and Cognitive Abilities in Older Adults

Changes to the while matter of the brain disrupt neural communication between spatially distributed brain regions and are associated with cognitive changes in later life. While approximately 95% of older adults experience these brain changes, not everyone who has significant white matter damage displays cognitive impairment. Few studies have investigated the association between white matter changes and cognition in the context of functional brain network integrity. This study used a data-driven, multivariate analytical model to investigate intrinsic functional connectivity patterns associated with individual variability in white matter lesion load as related to fluid and crystallized intelligence in a sample of healthy older adults (n = 84). Several primary findings were noted. First, a reliable pattern emerged associating whole-brain resting-state functional connectivity with individual variability in measures of white matter lesion load, as indexed by total white matter lesion volume and number of lesions. Secondly, white matter lesion load was associated with increased network disintegration and dedifferentiation. Specifically, lower white matter lesion load was associated with greater within- versus between-network connectivity. Higher white matter lesion load was associated with greater between-network connectivity compared to within. These associations between intrinsic functional connectivity and white matter lesion load were not reliably associated with crystallized and fluid intelligence performance. These results suggest that changes to the white matter of the brain in typically aging older adults are characterized by increased functional brain network dedifferentiation. The findings highlight the role of white matter lesion load in altering the functional network architecture of the brain

Utvrđivanje sintaktičke konvergencije u dvojezičnih govornika ruskoga jezika i jezika sakha

This paper illustrates the implementation of two basic experiments to test word order changes in Russian and Sakha, languages in long–standing contact. We hypothesize that changes in word order may correlate with deeper structural changes and la nguage shift. The experiments show that some speakers are shifting from Sakha to Russian: 4 from a sample of 30 speakers could not produce texts in Sakha, and one third of the sample produced sentences with some errors. At the same time, there were a significant number of mistakes in the Russian production experiments, indicating interference from Sakha and/or imperfect learning. A sociolinguistic questionnaire showed a high level of accuracy between speakers’ self–assessment of their proficiency in each of the target languages as measured by the experiments shown here. Moreover, the simple experiments themselves revealed a number of other production errors and proved to be a reasonable indicator of less than fluent proficiency and of at least the initial stages of language shift.Članak pokazuje primjenu dvaju osnovnih testova za provjeru promjena u poretku riječi u dvama jezicima u dugogodišnjemu kontaktu: u ruskome jeziku i u jeziku sakha (ili jakutskom). Pretpostavka je da promjene u poretku riječi mogu biti povezane s dubljim strukturnim promjenama i gubitkom jezika. Istraživanja pokazuju da neki govornici prestaju rabiti jezik sakha jer govore ruski: u skupini od 30 govornika četvero ih ne može proizvesti tekst na jeziku sakha, dok je trećina ispitanika proizvela rečenice s pogreškama. Istodobno, u proizvodnji tekstova na ruskome također je zabilježen znatan broj pogrešaka koje su odražavale interferencije s drugim jezikom (sakha) ili su posljedica loše usvojenoga jezika. Sociolingvistički je upitnik pokazao visoku razinu podudarnosti između samoprocjene jezične kompetencije govornika u svakome od proučavanih jezika i rezultata naših mjerenja. Štoviše, i vrlo jednostavne provjere kompetencije pokazale su stanovit broj ostalih vrsta pogrešaka te dokazale da su pouzdan pokazatelj sve slabije tečnosti u govoru kao i neupitno početne faze gubitka jezika

Reconstructing sociolinguistic variation

In this paper we illustrate a methodology for reconstructing language in interaction from literary texts, demonstrating how they can serve as documentation of speech when primary linguistic material is unavailable. A careful incorporation of facts from literary dialect not only informs grammatical reconstruction in situations with little to no documentation, but also allows for the reconstruction of the sociolinguistic use of a language, an oft-overlooked aspect of linguistic reconstruction. Literary dialogue is often one of the only attestations of regional varieties of a language with a very salient standard dialect, where no primary sources are available. Odessan Russian (OdR), a moribund dialect of Russian, serves as a case study. OdR grew out of intensive language contact and differs from most other varieties of Russian, with substrate influences from Yiddish, Ukrainian, and Polish, and lexical borrowing from other languages. The only records of "spoken" OdR are found in fctional narrative. An analysis of works from several prominent Odessan writers, including Isaak Babel and Ze'ev Jabotinsky, reveals considerable variation among speakers of OdR; careful tracking of this variation shows how it was distributed among different social groups, and suggests how it may have been deployed to index and acknowledge different social roles

Repensando la Universidad : Algunos aportes para la discusión

En el presente trabajo nos proponemos retomar algunos argumentos que circulan desde hace tiempo acerca de la universidad y su crisis. Crisis que, consideramos, es en parte producto de una serie de procesos de transformación que han tenido lugar en las últimas décadas en nuestro país. En este sentido no se puede dejar de analizar la crisis de la Universidad como un proceso complejo atravesado por políticas de Estado que han tenido evidentes impactos en todo el sistema. Sin embargo pensar la crisis universitaria circunscribiéndola sólo a tales procesos nos brinda una mirada parcial de lo que sucede al interior de la misma. Por tal motivo intentaremos avanzar en la búsqueda de otros sentidos de la crisis que nos permitan dar cuenta de sus múltiples dimensiones que la definen. Por otro lado, intentaremos esbozar algunas reflexiones acerca de lo que consideramos es una alternativa posible para pensar nuevas funciones y nuevos roles de la Universidad pública, aunque advirtiendo su complejidad en el contexto actual en el que la universidad se inscribe.Facultad de Humanidades y Ciencias de la Educació

A Nanosensor for TNT Detection Based on Molecularly Imprinted Polymers and Surface Enhanced Raman Scattering

We report on a new sensor strategy that integrates molecularly imprinted polymers (MIPs) with surface enhanced Raman scattering (SERS). The sensor was developed to detect the explosive, 2,4,6-trinitrotoluene (TNT). Micron thick films of sol gel-derived xerogels were deposited on a SERS-active surface as the sensing layer. Xerogels were molecularly imprinted for TNT using non-covalent interactions with the polymer matrix. Binding of the TNT within the polymer matrix results in unique SERS bands, which allow for detection and identification of the molecule in the MIP. This MIP-SERS sensor exhibits an apparent dissociation constant of (2.3 ± 0.3) × 10−5 M for TNT and a 3 μM detection limit. The response to TNT is reversible and the sensor is stable for at least 6 months. Key challenges, including developing a MIP formulation that is stable and integrated with the SERS substrate, and ensuring the MIP does not mask the spectral features of the target analyte through SERS polymer background, were successfully met. The results also suggest the MIP-SERS protocol can be extended to other target analytes of interest

Argument Structure in Language Shift: Morphosyntactic Variation and Grammatical Resilience in Modern Chukchi

Despite the growing interest in endangered languages, relatively little attention has been paid to the ways in which the structure of these languages is conditioned by the language shift setting, even among conservative older speakers. This thesis investigates how the social circumstances of language endangerment---which include disrupted intergenerational transmission, loss of a cohesive speech community, pressure to master a new dominant language, and stigmatization of the traditional language---can have significant grammatical effects. I investigate morphosyntactic variation among different groups of speakers of the highly endangered polysynthetic indigenous language Chukchi, which is spoken in northeastern Russia. Following a series of disruptive social and educational policies implemented in the mid-20th century, speakers of Chukchi rapidly shifted to Russian; today, virtually all speakers are bilingual in Russian and transmission of Chukchi to children has ceased entirely. In order to systematically compare linguistic patterns among speakers of different backgrounds (proficient older speakers, attriting speakers, and young L2 or heritage learners), I utilize a combination of traditional fieldwork techniques and controlled experimental production tasks. I focus on several distinct reflexes of the encoding of argument structure, which cuts across multiple morphosyntactic domains and thus affords us the opportunity to examine not only individual grammatical changes due to language shift, but also system-wide grammatical restructuring that can only be seen as a direct result of the modern sociolinguistic setting. Modern Chukchi speakers evidence variation across the following domains: agreement marking, morphological and syntactic ergativity, valency-changing derivational morphology, verbal and nominal incorporation, and argument drop. While older, highly proficient speakers display patterns that are largely consistent with existing grammatical descriptions, attriting speakers and L2 speakers show deviations from the expected patterns, though not always in identical ways. Attriting and L2 speakers reanalyze agreement marking across different dimensions, and while both groups make little productive use of verbal derivation and incorporation, this tendency is more pronounced among L2 learners. However, these varieties are alike in that the changes present in the grammars of these speakers are entirely consistent with cross-linguistic tendencies and a shift away from a polysynthetic configuration. Furthermore, while similar changes in other moribund languages have often been characterized as "linguistic loss," the Chukchi data show that as certain features are lost, speakers innovate new patterns to replace them, often making use of existing resources in the language (rather than borrowing from or replicating patterns in the contact language)

Transmission of narratives among former Soviet Union (FSU) émigrés

This qualitative study explores the stories told by Former Soviet Union (FSU) Jewish émigré parents to their American-reared children about their experiences of life in the FSU and their reasons for emigration. Specifically, this study examines whether the stories transmitted reflect the mass oppression, suppression and state-sponsored brutality exacted upon Soviet Jews. The sample consisted of twelve participants between the ages of 18-35, all of whom had at least one parent who emigrated from the FSU. The analysis revealed the following noteworthy findings: 1) All twelve participants inherited stories depicting the collective discrimination that Jews were forced to endure under the Soviet regime; 2) The narratives of Central Asian Jews reflected a more positive association with the FSU than did the accounts transmitted by Eastern-European Jews, suggesting critical regional and cultural differences despite their mutually shared identity as FSU Jewish émigrés; 3) The transmission of the collective discrimination imposed upon the Jewish population in Soviet Russia and the personal implications of Soviet Anti-Semitism for their parents was influential in shaping the participants\u27 identity; (4) The narratives were communicated both directly and indirectly and shared often, suggesting the prevalence of such a practice among FSU Jewish families in the United States; (5) The participants\u27 parents\u27 explicit communication of their expectations implicitly told the story of their lives in the FSU and their reasons for emigration; (6) These expectations were communicated with an intensity and drive that was often internalized by the American-reared children

Investigating White Matter Lesion Load, Intrinsic Functional Connectivity, and Cognitive Abilities in Older Adults

Changes to the while matter of the brain disrupt neural communication between spatially distributed brain regions and are associated with cognitive changes in later life. While approximately 95% of older adults experience these brain changes, not everyone who has significant white matter damage displays cognitive impairment. Few studies have investigated the association between white matter changes and cognition in the context of functional brain network integrity. This study used a data-driven, multivariate analytical model to investigate intrinsic functional connectivity patterns associated with individual variability in white matter lesion load as related to fluid and crystallized intelligence in a sample of healthy older adults (n = 84). Several primary findings were noted. First, a reliable pattern emerged associating whole-brain resting-state functional connectivity with individual variability in measures of white matter lesion load, as indexed by total white matter lesion volume and number of lesions. Secondly, white matter lesion load was associated with increased network disintegration and dedifferentiation. Specifically, lower white matter lesion load was associated with greater within- versus between-network connectivity. Higher white matter lesion load was associated with greater between-network connectivity compared to within. These associations between intrinsic functional connectivity and white matter lesion load were not reliably associated with crystallized and fluid intelligence performance. These results suggest that changes to the white matter of the brain in typically aging older adults are characterized by increased functional brain network dedifferentiation. The findings highlight the role of white matter lesion load in altering the functional network architecture of the brain