The increasing prevalence of acquired brain injury and other disorders that impair cognitive control has prompted calls for more ecologically valid neuropsychological tests. The Medication Scheduling Task was designed with this idea in mind, and its independence from motor ability further extends its applicability. Cross-validation of the task on 883 healthy participants aged 18-79 years found a two-factor structure, which, when compared with correlations of several tests of working memory and executive function, offered a substantive interpretation of the factors: (1) a cognitive control factor and (2) factor of accuracy. The study also included 31 people with acquired brain injury who, in addition to the aforementioned tests, also completed clinically established tests of attention, verbal learning and memory, and executive function. Individual comparisons of the clinical participants' performance with matched control participants (±3 years of variance in years of education and age) indicate significantly lower cognitive control performance of the clinical participants, but not lower accuracy. In both healthy and clinical participants, cognitive control performance declined with increasing age. Higher education had a positive effect, though statistically significant only in patients with prefrontal lobe damage. The score on the cognitive control factor correctly classifies a person as healthy (effective cognitive control) or cognitively impaired (significantly reduced cognitive control) in 83.4% of cases, indicating a high discriminatory ability.
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