What can we learn from replication failures in the quest for interpreter advantages in cognitive control?

Previous research has generated mixed results with regards to the interpreter advantage in cognitive control (Yudes, Macizo, & Bajo, 2011). In a systematic review based on the unity/diversity model of cognitive control (Miyake et al., 2000), we showed that different components of cognitive control (i.e., Inhibition, Shifting, Updating) may be differently influenced by expertise and/or training in interpreting (Nour et al., in preparation). Most crucially, a distinction was found between the impact on shifting and updating skills, with a selective effect of interpreter training on shifting abilities only. In a longitudinal design, we tested Inhibition (Attention Network Test (ANT)), Shifting (bilingual categorization task) and Updating (reading span test) skills in 15 students of interpreting and we compared their performance to 12 students of translation. All participants were tested at the beginning and at the end of their training, with an 8-month interval between the two tests. We did not find any effects on the Shifting and Updating components. The analyses of the ANT, however, revealed a puzzling triple interaction effect between congruency, cue type and group (p = .02). In fact, the group of interpreters showed higher progress on incongruent trials with a central cue. Our results are only partially in line with those from a recent study with a similar design that found significant effects of interpreter training on Shifting and Updating, but not on Inhibition (Dong & Liu, 2016). We interpret our findings in light of the similar discussion on the bilingual advantage in cognitive control (e.g., von Bastian, Souza, & Gade, 2016). We suggest a theory-based approach to the relationship between interpreting expertise and training, in an attempt to explain expertise- and training-related plasticity in the interpreter brain (Elmer, Hanggi, & Jancke, 2014; Hervais-Adelman, Moser-Mercer, & Golestani, 2015).