Background: The Symbol Digit Modalities Tests (SDMT) is the most sensitive measure to multiple sclerosis (MS)related cognitive dysfunction. However, existing normative data has been under scrutiny. Specifically, they are outdated, do not take into account gender, and are poorly stratified by education. More importantly, there exists no oral only version norms, which is typical administration among individuals with MS. Objective: The present investigation aimed to develop updated normative data of the oral version SDMT in which age, gender, and education were taken into consideration. Methods: A total of 675 healthy individuals, stratified by age, gender, and education completed the oral version SDMT. Results: Significant effects were found for age, gender, and education, consistent with previous contentions. Specifically, performance on the SDMT tends to decline with age, with the most noticeable decline beginning in the third decade of life and continuing into the sixth decade. Women, in general perform better than men, with an average of 5.1 more points. Finally, education effects were apparent among those aged 25-54. Conclusion: Based on these findings, updated normative data are provided. Utilization of these updated norms will result in a much needed and more accurate assessment of processing speed for individuals with MS.

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Studies of statistical learning have shaped our understanding of the processes involved in the early stages of language acquisition. Many of these advances were made using experimental paradigms with artificial languages that allow for careful manipulation of the statistical regularities in the input. This article summarizes how these paradigms have begun to inform bilingualism research. We focus on two complementary goals that have emerged from studies of statistical learning in bilinguals. The first is to identify whether bilinguals differ from monolinguals in how they track distributional regularities. The second is determining how learners are capable of tracking multiple inputs, which arguably is an important facet of becoming proficient in more than one language.

Bilinguals show word use patterns in each of their languages that differ from those of monolinguals. One interpretation is that, for bilinguals, the word meanings of one language are influenced by those of the other. Another is that the cross-language influence lies in on-line processes – word retrieval probabilities or word form activation levels. To discriminate between interpretations, we asked Mandarin–English bilinguals to name household objects in their L1 and L2 via forced choice instead of free production. The options given were the monolingual-preferred choices, eliminating memory retrieval demands and keeping those words at a high level of activation. For comparison, monolinguals of each language performed the same task in their native language. Differences from monolinguals in word choice were substantially reduced, especially in L1, but bilingual patterns still showed some cross-language influence in both L1 and L2. This outcome implicates cross-language influences on both bilingual processing and meaning representations.

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