The effects of second language proficiency and language distance on young adults' executive functioning performance

Abstract

The bilingual advantage hypothesis suggests that knowing and controlling more than one language enhances cognitive capacities. While there are studies that have shown a positive relationship between bilingualism and various cognitive factors there is also a growing literature finding no difference between monolinguals and bilinguals. Finding pure monolinguals has become almost impossible, especially in the young adult population. Hence, this study aims to investigate two bilingual groups that have different genetic language distances between their first language (L1) and second language (L2) (i.e., L1-Turkish-L2-English and L1-Turkish-L2-Arabic) and examine whether language proficiency plays a role in task performances of executive functioning (henceforth EF). The sample of the study consisted of 108 participants with Turkish as their first language, 55 of which had English as their second language (Female = 40, Male = 15, Mage = 22.96) and 53 with Arabic as their L2 (Female = 40, Male = 13, Mage = 22.05). We collected data in two sessions; the first session included computerized versions of the Stroop task as a measure of inhibition, Wisconsin Card Sorting Task for cognitive flexibility and 2-Back for verbal working memory and both the forward and backward Corsi Block tests for spatial working memory. The second session included the second language proficiency task PPVT-IV, Penn Matrix Analysis Test (PMAT24) as a measure of non-verbal reasoning, and the letter verbal fluency task to control for L1 fluency. The findings suggest that L2 proficiency was not a significant predictor of EF task performance in our sample. Additionally, the genetic language distance score in our study was based on how distant the languages originated from one another. However different aspects of language distance such as orthography and word borrowing can play a role in how language distance effects EF performance therefore, they can be considered for future studies.