Previous research has shown that bilinguals'two languages are activated whenever they prepare to speak, even if the context requires only one language to be spoken. Past studies have demonstrated that words in the other language can become active to the extent that their articulatory information is available, enabling these words to compete with words in the intended language. Despite the persistent activation of the other language, bilinguals rarely make accidental language intrusions when speaking. This suggests that bilinguals exploit a sophisticated mechanism for controlling the two languages. How do bilinguals control their two languages when planning to select just the word in the intended language? One account of bilingual language control proposes that inhibition is used to competition between words in the two languages. The inhibitory account is also consistent with evidence that has revealed bilingual advantages in executive functions. Evidence shows that bilinguals outperform monolinguals on tasks that require suppression of irrelevant actions, switching between two sets of responses, and attending to cued information. While it is tempting to think that bilingual language experience is the direct cause of the benefits to bilinguals'executive functions, there is no direct evidence that links bilingualism to enhanced cognitive abilities. However, it has been speculated that controlling the two languages in order to select the right word during speech planning is the particular aspect of bilingual language experience that strengthens executive functions. There are still some aspects of the inhibitory account of bilingual language control that need to be addressed in order to advance this account of bilingual cognitive advantages beyond speculation. Recent studies have begun to address whether inhibition is required for bilingual speech production and the available evidence does suggest that inhibition underlies bilingual speech planning. However, these studies have not yet examined particular properties of the inhibitory mechanism. The planned research program will investigate the scope (what is inhibited) and time course of inhibition (when it occurs) during speech planning by conducting a series of experiments that will adopt electrophysiological methods (ERPs) to track the earliest processing in the brain. These brain recordings will be examined within the context of an extended picture naming task, in which the long-term patterns of inhibition can be tracked. Long term consequences of inhibition have scarcely been studied, but have real-world implications for bilingual immigrants. Bilinguals and monolinguals will name pictures across an initial block of naming and several successive blocks while ERPs and behavioral measurements are collected. Previous evidence suggests global inhibition of the dominant language (inhibition of words in the entire language) occurs to enable bilinguals to speak in their weaker language after using their dominant language. The planned research will investigate whether or not the inhibition of the dominant language found is global in scope and how long the inhibition lasts in the earliest moments in time that ERPs can capture and the larger time-frame of the task.
Every time bilinguals intend to produce a single word in one of their two languages they must avoid speaking highly active alternative words in the other language. This research aims to investigate whether suppression of words in the language not-to-be-spoken allows bilinguals to speak words in the intended language, how long this suppression may last, and its cognitive consequences.
| Boutonnet, Bastien; McClain, Rhonda; Thierry, Guillaume (2014) Compound words prompt arbitrary semantic associations in conceptual memory. Front Psychol 5:222 |
