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Almost all of our everyday activities depend on executive function (EF) skills. In line with the increasing attention to the ecological validation of neuropsychological assessment and intervention methods, this study aimed to explore the ecological validity of a relevant set of widely used EF tests, mostly from well-known paradigms of EF assessment, in predicting driving ability. Ninety-six healthy novice drivers ( M age  = 26.2 years, SD  = 8.4; 48 female) completed four stages of our data collection including psychological, EF, and driving assessments. For the psychological assessment, validated measures of sensation-seeking, risk-taking, personality traits, ADHD symptoms, depression, anxiety, and stress were administered. For the EF assessment, selected tests from the Delis-Kaplan Executive Function System (D-KEFS: Trail Making, Design Fluency, and Tower) and the Behavioral Assessment of the Dysexecutive Syndrome (BADS: Key Search, Zoo Map, and Modified Six Elements) along with a computerized Stroop test were administered. For the driving assessment, we used a simulated driving test comprising of 14 key dimensions of driving skills. Several correlations and multiple regression analyses were conducted. Significant correlations were found between all the EF measures and driving performance. Moreover, the EF measures predicted the driving ability over and above the effects of previous driving experience and the psychological variables. These results provide supporting evidence for the ecological validity of the EF tests in predicting driving performance. The incorporation of assessment and intervention targeting multiple domains of EF into driving rehabilitation and education programs could be a focus of future research.

Human factors, including the level of cognitive functioning, are the most influential factors in road traffic crashes. Among cognitive abilities, executive functions (EFs) of the brain play a pivotal role in driving performance and outcomes, including crash numbers. The current study was aimed to explore, for the first time, the ability of EF tests to predict success on the official driving tests in applicants of driving license in Iran. We administered a relevant set of commonly used EF tests, including a computerized Stroop test and six tests from the Delis-Kaplan Executive Function System (D-KEFS) and the Behavioral Assessment of the Dysexecutive Syndrome (BADS), to 87 healthy new drivers applying for a driver's license ( M age = 25.9 years, SD  = 8.2; 43 female). We also administered a series of demographic and psychological questionnaires. The data regarding the participants' official driving tests were extracted from the official records. To determine the relations of the EF tests with success on the driving tests, several correlation and regression analyses were conducted. Most of the EF measures had significant correlations with the road test success, while having no significant relations with the theory test success. Moreover, in our regression analyses, The EF measures predicted success on the official driving road test, but not success on the driving theory test, even after controlling for the effects of previous unlicensed driving experience and stress symptoms. The results demonstrate the predictability of the driving road test success from executive functioning.

Executive dysfunctions are among the most prevalent neurobehavioral sequelae of traumatic brain injuries (TBIs). Using culturally validated tests from the Delis-Kaplan Executive Function System (D-KEFS: Trail Making, Verbal Fluency, Design Fluency, Sorting, Twenty Questions, and Tower) and the Behavioural Assessment of the Dysexecutive Syndrome (BADS: Rule Shift Cards, Key Search, and Modified Six Elements), the current study was the first to examine executive functioning in a group of Iranian TBI patients with focal frontal contusions. Compared with a demographically matched normative sample, the frontal contusion patients showed substantial impairments, with very large effect sizes (p ≤ .003, 1.56 < d < 3.12), on all the executive measures. Controlling for respective lower-level/fundamental conditions, the differences on the highest-level executive (cognitive switching) conditions were still significant. The frontal patients also committed more errors. Patients with lateral prefrontal (LPFC) contusions were qualitatively worst. For example, only the LPFC patients committed perseverative repetition errors. Altogether, our results support the notion that the frontal lobes, specifically the lateral prefrontal regions, play a critical role in cognitive executive functioning, over and above the contributions of respective lower-level cognitive abilities. The results provide clinical evidence for validity of the cross-culturally adapted versions of the tests.