This study aimed to characterize the digit span performances of cognitively healthy Chinese and White older adults as well as to investigate the neural basis underlying their respective digit span profiles.

Numerous studies have demonstrated that Chinese and English speakers differ in their digit span performances; however, the contributing factors remain uncertain. We hypothesize that the discrepancies in digits span performances between Chinese and White individuals are associated with the differences in language profile and the neural structures supporting the digit span tasks.

A total of 411 White Americans and 106 Chinese older adults were included and further categorized into four groups based on their race, primary language, and testing language: White-English-English (EEE), Chinese-Chinese-Chinese (CCC), Chinese-English-English (CEE), and Chinese-Chinese-English (CEE). All participants completed the forward and backward digit span tasks (FDS, BDS). We compared the group differences in FDS and BDS and analyzed their respective age and education effect via linear regression model. We examined the neural correlates of digit span performances via voxel-based morphometry analysis.

The heterogeneity in FDS performance and the asynchronous age effect on BDS scores highlight the importance of race and language considerations in the implementation of neuropsychological tasks and the development of normative values. Population-specific validation can potentially improve the neuroanatomical interpretation of cognitive tasks.