Abstract
Objective
Traumatic brain injury (TBI) survivors often exhibit problems with executive function (EF). Language use can also impact EF test performances. We examined the effects of TBI and bilingualism/monolingualism on several EF tests.
Method
The sample (N = 94) consisted of 37 healthy controls (19 bilingual; 18 monolingual), 30 acute TBI participants (10 bilingual; 20 monolingual), and 27 chronic TBI participants (16 bilingual; 11 monolingual). Acute TBI participants were tested 6 months post-injury and chronic TBI participants were tested 12 months or more post-injury. Stroop Color-Word (SCW), Delis-Kaplan Executive Function System Letter Fluency (DKEFS-LF), Trail Making Test part B (TMT-B) and a EF global composite (EF-GC) were used to assess EF. All participants passed performance validity testing. 3X2 ANOVAs were conducted to determine the effect of TBI and bilingualism/monolingualism on EF performances.
Results
Main effects were found between groups (control and TBI groups) on SCW, p = .046, ηp² = .07, TMT-B, p = .042, ηp² = .07, and EF-GC, p = .005, ηp² = .13; the 6-month TBI group performed worse than controls on TMT-B and EF-GC. Main effects were found for bilingualism/ monolingualism on SCW, p = .012, ηp² = .07, and TMT-B, p = .034, ηp² = .05; monolingual participants performed better than bilingual participants. No significant interactions between TBI and language were found.
Conclusion
The TBI group underperformed on SCW, TMT-B, and EF-GC compared to controls; relative to monolinguals, bilinguals underperformed on the SCW and TMT-B only. In conclusion, our findings seem to suggest that monolinguals have better cognitive flexibility compared to bilinguals that result in better EF performances.
Effects of Distraction on Performance Validity: A Pilot Study with Veterans
