The effects of acculturation on neuropsychological test performance in English-speaking and Farsi-speaking Iranian individuals

The aims of this study were to (1) characterize and provide descriptive statistics for the neuropsychological test performance of both English-Speaking and Farsi-Speaking Iranian individuals on three measures that involve little verbal mediation, (2) examine differences in the performance of English-Speaking Iranians, Farsi-Speaking Iranians, and Caucasians on three measures that require very little verbal mediation and are typically regarded as culture-free, and (3) assess the relationship between cultural factors and neuropsychological test performance of the English-Speaking and Farsi-Speaking Iranians. One-hundred-eight healthy adult participants composed three groups in this study: 44 Caucasian, monolingual English-speakers, 28 English-Speaking Iranian, and 36 Farsi-Speaking Iranian. Participants' performance on the Wisconsin Card Sorting Test (WCST), Trail Making Test (TMT), and Color Trails Test (CTT) was assessed. Results from a MANCOVA, using age as the covariate, indicated that group means were significantly different for the WCST percent conceptual response score, TMT-A, and TMT-B. Specifically, the Farsi-speaking Iranian group had lower conceptual level scores and slower completion times for TMT-A and TMT-B compared to the English-speaking Iranian group and the Caucasian group, who performed the same. Additionally, correlation analyses revealed that the Iranian participants' (Farsi- and English-speaking) level of acculturation and percentage of education obtained inside the US were related to performance on several of the neuropsychological variables. These findings provide support for the presumption that culture affects performance on neuropsychological measures. Furthermore, it is imperative that clinicians, who administer neuropsychological tests to ethnically diverse individuals, account for the influence of specific cultural factors when interpreting test results.