Cognitive control in older Minnan-Mandarin and Hakka-Mandarin bidialectal adults: Advantages in Stroop-type tasks.

• We examined bidialectal benefits in 40 older monolingual and bidialectal adults. • Advantages extend beyond bilingualism to bidialectalism in some Stroop tests. • Bidialectal advantages emerge in Stroop color-word and Stroop day-night tasks. • Bidialectal advantages emerge in tasks resting heavily on inhibitory control. • Bidialectal advantages emerge in tasks with a high or mid level of difficulty. The effect of bidialectalism on older bidialectal adults' performance on cognitive tasks has received little attention in aging studies. The current research aimed to investigate older monolingual and bidialectal adults' performance on nonverbal and verbal cognitive tasks, including Simon, Stroop, flanker, and spatial n-back tasks. Bidialectalism and task effects were examined via a comparison of the monolinguals' and bidialectals' response latencies. Two experiments were conducted, which consisted of four nonverbal tasks (Experiment 1) and four verbal tasks (Experiment 2), respectively. The participants were 20 older Mandarin monolingual adults and 20 older Minnan-Mandarin/Hakka-Mandarin bidialectal adults from Taiwan. The results indicated that the bidialectals performed better than the monolinguals on the nonverbal and verbal Stroop color-word tasks and the verbal Stroop day-night task. The nonverbal tasks revealed no significant interaction of task and language group, while the verbal tasks showed the opposite results. These findings suggest that the advantages in cognitive control extended beyond bilingualism to bidialectalism. Moreover, the bidialectal advantage was found in some tasks which involved more attentional and inhibitory control and had a high or intermediate level of task difficulty, and was absent in other tasks. [ABSTRACT FROM AUTHOR]