Abstract
OBJECTIVE: This study investigates the development of mental rotation skills in male and female youth from a longitudinal study at ages 9/10 (baseline), 11/12 (Year 2), and 13/14 (Year 4) using a relatively novel task, the Little Man Task. METHOD: The Little Man Task consists of four humanoid figures holding an object in either hand and rotated on two axes at 0° or 180°. Participants were prompted to indicate which of the figure's hands (left or right) was holding the object. Overall task performance (accuracy and response time on correct trials) and performance for individual orientations were obtained. Youth (n = 4,157) were drawn from the population-based, demographically diverse sample of the Adolescent Brain Cognitive Development Study. RESULTS: Conditional growth models for overall accuracy revealed main effects for age (representing the time variable) and sex. Effect sizes for sex effects were small and interactions between age and sex were not observed. There was a large main effect for orientation accompanied by small effect sizes for the interactions of orientation by age and orientation by sex. Exploratory descriptive data revealed that accuracy on the easiest orientation approximated asymptote at Year 4, whereas performance on the most difficult orientation remained relatively poor. CONCLUSIONS: Results demonstrate that rotational skills emerge early but are incompletely developed at midadolescence. Despite task characteristics optimized to detect sex differences, substantive differences were minimal. Further insight could be gained by incorporating an evaluation of evolving response strategies. (PsycInfo Database Record (c) 2025 APA, all rights reserved).