Some challenges for the triadic model for the study of adolescent motivated behavior.

Within this special issue, Ernst has provided a comprehensive overview of the triadic neural systems model and its explanatory power for the conceptualization of adolescent development. Within this commentary, we encourage further consideration of several issues as this valuable model is expanded and articulated. These issues include the extent of functional distinctions among the three proposed neural nodes that comprise the triadic framework, the proposed dichotomy between motivation and emotion as linked to approach versus avoidance, the extent to which approach and avoidance can be dissociated on behavioral and neural levels during adolescent development, and how individual difference factors mechanistically interact with broader age-based developmental trends.