RESUMO
OBJECTIVE: The present study examined how years of immersion in a nondominant language affect (a) the degree of bilingualism as measured by picture naming scores and (b) the bilingual disadvantage relative to monolinguals. METHOD: Forty-two older Spanish-English bilinguals named pictures in an expanded rapid administration version of the Multilingual Naming Test (MINT Sprint 2.0) in both languages and completed a language history questionnaire. English-speaking monolinguals (n = 138; from Gollan et al., 2024) named pictures in just one language. RESULTS: Spanish-dominant bilinguals named more pictures in the nondominant language but fewer pictures in the dominant language relative to English-dominant bilinguals. Increased years of immersion in the nondominant language increased naming scores in that language but decreased naming scores in the dominant language. When controlling for differences in age and education level, monolinguals named more pictures than bilinguals even in their dominant language, a difference that was numerically smaller for English-dominant bilinguals. However, two bilinguals who stated that they prefer to be tested in English scored much higher in Spanish. CONCLUSIONS: Older bilinguals name fewer pictures than demographically matched monolinguals even when bilinguals are tested in their dominant language and especially if they report many years of immersion in their nondominant language. The bilingual disadvantage can be magnified if self-reported language preference is used to determine the language of testing. Accurate interpretation of bilingual picture naming scores requires a thorough language history and objective assessment in both languages, which can be done in relatively little time using rapid administration procedures. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
RESUMO
Although cognitive and behavioral deficits are well known to occur following traumatic brain injury (TBI), motor deficits that occur even after mild trauma are far less known, yet are equally persistent. This study was aimed at making progress toward determining how the brain reorganizes in response to TBI. We used the adult rat controlled cortical impact injury model to study the ipsilesional forelimb map evoked by electrical stimulation of the affected limb, as well as the contralesional forelimb map evoked by stimulation of the unaffected limb, both before injury and at 1, 2, 3, and 4 weeks after using functional magnetic resonance imaging (fMRI). End-point c-FOS immunohistochemistry data following 1 h of constant stimulation of the unaffected limb were acquired in the same rats to avoid any potential confounds due to altered cerebrovascular coupling. Single and paired-pulse sensory evoked potential (SEP) data were recorded from skull electrodes over the contralesional cortex in a parallel series of rats before injury, at 3 days, and at 1, 2, 3, and 4 weeks after injury in order to determine whether alterations in cortical excitability accompanied reorganization of the cortical map. The results show a transient trans-hemispheric shift in the ipsilesional cortical map as indicated by fMRI, remote contralesional increases in cortical excitability that occur in spatially similar regions to altered fMRI activity and greater c-FOS activation, and reduced or absent ipsilesional cortical activity chronically. The contralesional changes also were indicated by reduced SEP latency within 3 days after injury, but not by blood oxygenation level-dependent fMRI until much later. Detailed interrogation of cortical excitability using paired-pulse electrophysiology showed that the contralesional cortex undergoes both an early and a late post-injury period of hyper-excitability in response to injury, interspersed by a period of relatively normal activity. From these data, we postulate a cross-hemispheric mechanism by which remote cortex excitability inhibits ipsilesional activation by rebalanced cortical excitation-inhibition.
