Abstract:

Interpreting is an intensive language switching task, and it may thus bring additional benefits to the interpreter’s switching ability on top of what benefits may be produced from general bilingual experience. This paper is a review of the relevant findings of interpreter advantages in switching, hoping to shed light on the more general issue of bilingual advantages in switching.
Switching ability could be very complex, and sorting out its complexity as revealed in the literature may help find out the patterns or mechanisms of interpreters’ switching ability. First of all, switch could be either “rule-based” or “task-based”, typically and respectively measured by the Wisconsin Card Sorting Test and the color-shape switching task. On the one hand, interpreters have shown advantages in both types of switching ability in the literature. On the other, the patterns of results differ between the advantages in rule-based switch and in task-based switch. To be specific, interpreters’ advantage is relatively more stable in rule-based switch, but empirical studies are not consistent regarding task-based switch. A review of the literature seems to show that there is a developmental change. That is, interpreting training may first bring about an advantage in local switch (indexed by switch cost in a univalent switching task), and then later an advantage in global monitoring (indexed by mixing cost in a bivalent switching task). 
The above patterns of results (i.e., stable advantage in rule-based switch; developmental change from local-switch advantage to global-switch advantage in task-based switch) can be accounted for by the control features of interpreting (heavy load of working memory, high demands on cognitive resources). To illustrate, interpreting is a complex task that involves multiple control processes, in which working memory serves as an indispensable module of control. Previous studies have shown that interpreters exhibit a stable advantage in working memory. It is speculated in this paper that the rule-based switch is probably more dependent on working memory than the task-based switch, which may explain why the interpreter advantage in the rule-based switch is more stable than that in the task-based switch. Besides, interpreting puts high demands on different processes of language switching. With limited cognitive resources, beginning student interpreters may find it necessary to first fulfill local switching between two languages so as to catch up with the speed of the task. With more training and more experience, interpreters may become more comfortable in switching between two languages, and thus more cognitive resources are available for globally monitoring the interpreting process. In short, the developmental change from local switch to global monitoring could be attributed to an improvement of efficiency in utilizing cognitive resources.
In addition, since interpreter advantage is generally defined as additional benefits when compared with general bilingual experience, the presence of an interpreter advantage must be related to how interpreting tasks differ from general bilingual communications tasks. As regards interpreter advantages in switching, interpreting requires switching between two languages under extreme time pressure, reflecting high intensity in language switching. To test the effect of language switching intensity on the presence of a switching advantage, some studies have compared written translation training with interpreting training. The logic is that written translation requires frequent language switch similar to interpreting, and yet language switch is less intensive in written translation (without time constraint) than in interpreting. The results show that the training of written translation does not bring additional benefits to the trainees’ switching ability as interpreting training does when compared with general bilinguals.
The above analysis of interpreter advantages in switching have implications for research on the controversial issue of bilingual advantage. By examining the distinctive features of interpreting, we gained a preliminary understanding of the factors influencing interpreter advantages in switching. Similarly, to clarify the controversy in general bilingual switching advantages, it may be helpful to analyze the specialty of the bilingual experience involved. That means: First, a careful characterization of bilinguals’ language experience is necessary, including whether the bilinguals have interpreting experience and even intensive monolingual experience (e.g., public speaking). Second, some bilinguals do not demonstrate any advantage in switching ability probably because their bilingual experience fails to reach the intensity level of language switching required for generating a switching advantage. Third, in terms of the theories of bilingual language switching, the control features of different bilingual experiences are also worth being taken into account.

Key words: switching ability, interpreter advantage in switching, rule-based switch, task-based switch, bilingual advantage