Adolescent development of decision making processes in n-back task performance and links to pubertal timing and tempo

Adolescence is associated with substantial improvements in cognitive performance, with faster and more accurate decisions, yet the underlying mechanisms and the role of pubertal maturation remain unclear. Pubertal maturation can be characterized by timing, capturing whether an individual reaches pubertal milestones before or after peers, and tempo, capturing how fast one progresses through puberty relative to peers. We applied computational modeling to examine developmental changes in decision making and working memory and tested whether pubertal timing and tempo explain variance beyond age.

Using longitudinal data from 4194 participants (ages 9-17 years) in the Adolescent Brain Cognitive Development^SM (ABCD Study®), we characterized the development of accuracy, response times, and drift diffusion model parameters from an n-back task with generalized additive mixed models. Next, we compared age-only and puberty-informed models to test whether pubertal timing and tempo explain variance in cognitive development.

We observed non-linear improvements in performance and all model parameters, with the largest changes in drift rate and non-decision time, indicating more efficient processing and faster non-decision processes. Additional non-linear changes in decision threshold, capturing the speed-accuracy tradeoff, and choice bias suggest strategic shifts in response caution and task strategy. When controlling for sociodemographic variables, pubertal maturation was related to response times and drift rate in females.

This study shows that developmental improvements in n-back performance in youth are accompanied by increased information processing efficiency, faster non-decision processes, and adaptive decision policies, with weak links to individual differences in pubertal timing and tempo.