Instead of viewing organisms and individuals as passive recipients of their biological, ecological, and cultural inheritances, the developmental niche construction theory and the biocultural co-construction framework both emphasize that the individual's agency plays a key role in regulating how environmental and sociocontextual influences may affect the course of ontogeny. Indeed, target article by Flynn, Laland, Kendal and Kendal (2012), states that "infants and children both being directed, and directing, their own environment". In the author's own work on biocultural co-construction of developmental plasticity (Baltes, Reuter-Lorenz & Rosler, 2006; Li, 2003; cf. Gottlieb, 1998), it is underscored that individuals are not merely passive receivers of their biological and cultural inheritances; rather, individuals are active agents who make choices and take actions to regulate the available resources for promoting their own development (Li & Freund, 2005; cf. Baltes & Baltes, 1990; Ford, 1987; Freund, 2008). If individual agency is the active driver of developmental niche construction, then psychological and neurobiological mechanisms of adaptive cognitive control and motivation underlie the development of individual agency. In this commentary, the author thus hopes to add some specificity to one type of ontogenetic mechanism that is relevant for developmental niche construction. Specifically, the article focuses on the maturation and senescence of neurotransmitter systems, which play crucial roles in the development of executive control, motivation, and the regulation of reactions to social and environmental stressors. (Contains 1 figure.)