precortical control of behavior. In addition, DHEA/S’s antiglucocorticoid effects suggest a potentially important role for DHEA/S in memory development and the ability to produce novel behavior patterns in response to familiar stimuli, under conditions of arousal. The very fact that DHEA/S levels rise during maturation in humans represents an important evolutionary feature of the human life cycle that may shed light on the role of brain development and attachment in humans as well as fertility behavior more generally.

FUTURE RESEARCH DIRECTIONS

To more fully understand the implications of adrenarche for the development of boys, I suggest three important lines of investigation. The first of these is a better understanding of the interaction of DHEA/S and cortisol with testosterone in the disruption of normal emotional development in boys. The second is the study of cross-population differences in age-related patterns in adrenal and gonadal steroids and the insight they may provide into maturational timing. The third is a more detailed investigation of the role of adrenal and gonadal steroids on behavioral development in chimpanzees and gorillas as a background for understanding the truly human aspects of male reproductive maturation.

There is already sufficient evidence for the effects of cortisol and DHEA on major depressive disorder in adolescence to warrant further investigation (Goodyer et al., 2001). What the perspective offered here adds is a functional understanding that for adolescent boys mood dysregulation reflects not only the shifting patterns of psychosocial adjustment during this period but also the role of testosterone in producing the underlying motivations for attachment. DHEA/S, cortisol, and testosterone are only some of the many factors involved in this process, but they can help provide insight into the specific aspects of brain functioning that fail to develop normally in these conditions.

Researchers will also want to investigate the impact of variations in maturational timing across populations on the development of emotions and behavior. One very important issue in understanding the interaction of gonadal and adrenal steroids on adolescent maturation among boys is the role of DHEA/S in mediating the effects of testosterone on sexual behavior. If because of its relationship to brain growth, the timing of adrenarche is less variable than that of gonadarche (Worthman, 1993), individuals in early-maturing populations such as our own may be exposed to the maturational effects of DHEA/S for a much shorter time before being exposed to the sexually motivating effects of testosterone. Faster rates of maturation among adolescent boys may simply provide less time for the effects of



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