Growth Trajectories of Cognitive and Motor Control in Adolescence: How Much Is Development and How Much Is Practice?

Objective: Executive control continues to develop throughout adolescence and is vulnerable to alcohol use. Although longitudinal assessment is ideal for tracking executive function development and onset of alcohol use, prior testing experience must be distinguished from developmental trajectories. Method: We used the Stroop Match-to-Sample task to examine the improvement of processing speed and specific cognitive and motor control over 4 years in 445 adolescents. The twice-minus-once-tested method was used and expanded to four test sessions to delineate prior experience (i.e., learning) from development. A General Additive Model evaluated the predictive value of age and sex on executive function development and potential influences of alcohol use on development. Results: Results revealed strong learning between the first two assessments. Adolescents significantly improved their speed processing over 4 years. Compared with boys, girls enhanced ability to control cognitive interference and motor reactions. Finally, the influence of alcohol use initiation was tested over 4 years for development in 110 no/low, 110 moderate/heavy age- and sex-matched drinkers; alcohol effects were not detected in the matched groups. Conclusions: Estimation of learning effects is crucial for examining developmental changes longitudinally. Key Points Question : This prospective study investigated the cognitive development of executive control processes (general efficiency, cognitive, and motor control) by controlling for learning effects (i.e., prior practice experience) and evaluated whether these trajectories are affected by alcohol use initiation. Findings : Strong learning effects were observed between the first two repetitions of the task, cognitive development was related to age, and alcohol use initiation has no significant effects. Importance : This study identified prior testing experience as an essential factor to be measured in longitudinal neuropsychological and alcohol research. Next Steps : Larger prospective evaluations are needed and should consider additional neuropsychological processes and alcohol consumption patterns.