Are simultaneous interpreters subject to the central processing bottleneck, which can postpone the reaction time and impair the performance of another concurrent task, during word production? Moreover, is there any difference between interpreters, bilinguals and monolinguals in the word production bottleneck? In this study, professional simultaneous interpreters, proficient bilinguals and monolinguals performed a dual task consisting of a picture naming task in sentence context (Task 1) and a pitch tone discrimination task (Task 2). The results show that interpreters are also subject to the central processing bottleneck during word production, and there is no significant difference between the three groups in the duration of the word production bottleneck. Unexpected differences in performance were found between English–Asian language and English–European language pairs within the interpreter group, but not within the bilingual group, showing that European-language interpreters were as fast as monolinguals in lexical access, and faster than Asian-language interpreters and bilinguals.

In a parity judgment task, the ERPs at parietal electrode sites become more negative as more mental rotation has to be executed. This article provides a review of the empirical evidence regarding this amplitude modulation. More specifically, experiments are reported that validate both the functional relationship between mental rotation and the amplitude modulation as well as the temporal relationship both in single- and in dual-task situations. Additionally, ERP effects are reported in the psychological refractory period (PRP) paradigm with mental rotation as the second task. Finally, unresolved issues are discussed that, I hope, might stimulate future research.