The language and social background questionnaire: Assessing degree of bilingualism in a diverse population.

Research examining the cognitive consequences of bilingualism has expanded rapidly in recent years and has revealed effects on aspects of cognition across the lifespan. However, these effects are difficult to find in studies investigating young adults. One problem is that there is no standard definition of bilingualism or means of evaluating degree of bilingualism in individual participants, making it difficult to directly compare the results of different studies. Here, we describe an instrument developed to assess degree of bilingualism for young adults who live in diverse communities in which English is the official language. We demonstrate the reliability and validity of the instrument in analyses based on 408 participants. The relevant factors for describing degree of bilingualism are: (1) the extent of non-English language proficiency and use at home, and (2) non-English language use socially. We then use the bilingualism scores obtained from the instrument to demonstrate their association with: (1) performance on executive function tasks, and (2) previous classifications of participants into categories of monolinguals and bilinguals.

Sequential congruency effects reveal differences in disengagement of attention for monolingual and bilingual young adults.

Three studies examined the hypothesis that bilinguals can more rapidly disengage attention from irrelevant information than monolinguals by investigating the impact of previous trial congruency on performance in a simple flanker task. In Study 1, monolingual and bilingual young adults completed two versions of a flanker task. There were no differences between language groups on mean reaction time using standard analyses for congruent or incongruent trials or the size of the flanker effect. Sequential congruency effects (SCEs) however, which account for previous trial congruency, were smaller for bilinguals than for monolinguals. This finding was strongest at the shortest response-to-stimulus interval (RSI). Study 2 replicated this effect using a slightly different flanker task and a shorter RSI than study 1. Study 3 showed that at long RSIs, where behavioral SCE differences between groups disappear because of sufficient time to recover from the previous trial, event-related potentials demonstrated a continued influence of previous trial congruency for monolinguals but not bilinguals at both the N2 and the P3, replicating the reaction time effects in Studies 1 and 2. Together, these studies demonstrate that bilinguals experience less influence from previous trial congruency and have greater ability to disengage attention from the previous trial in order to focus attention on the current trial than is found for monolinguals.

Words Get in the Way: Linguistic Effects on Talker Discrimination.

A speech perception experiment provides evidence that the linguistic relationship between words affects the discrimination of their talkers. Listeners discriminated two talkers' voices with various linguistic relationships between their spoken words. Listeners were asked whether two words were spoken by the same person or not. Word pairs varied with respect to the linguistic relationship between the component words, forming either: phonological rhymes, lexical compounds, reversed compounds, or unrelated pairs. The degree of linguistic relationship between the words affected talker discrimination in a graded fashion, revealing biases listeners have regarding the nature of words and the talkers that speak them. These results indicate that listeners expect a talker's words to be linguistically related, and more generally, indexical processing is affected by linguistic information in a top-down fashion even when listeners are not told to attend to it.