Schulz Kalynn M, Molenda-Figueira Heather A, Sisk Cheryl L
Department of Psychiatry and Developmental Psychobiology Program, University of Colorado, Denver Anschutz Medical Campus, Aurora, CO 80045, USA.
Horm Behav. 2009 May;55(5):597-604. doi: 10.1016/j.yhbeh.2009.03.010.
Phoenix, Goy, Gerall, and Young first proposed in 1959 the organizational-activational hypothesis of hormone-driven sex differences in brain and behavior. The original hypothesis posited that exposure to steroid hormones early in development masculinizes and defeminizes neural circuits, programming behavioral responses to hormones in adulthood. This hypothesis has inspired a multitude of experiments demonstrating that the perinatal period is a time of maximal sensitivity to gonadal steroid hormones. However, recent work from our laboratory and others demonstrates that steroid-dependent organization of behavior also occurs during adolescence, prompting a reassessment of the developmental time-frame within which organizational effects are possible. In addition, we present evidence that adolescence is part of a single protracted postnatal sensitive period for steroid-dependent organization of male mating behavior that begins perinatally and ends in late adolescence. These findings are consistent with the original formulation of the organizational/activational hypothesis, but extend our notions of what constitutes "early" development considerably. Finally, we present evidence that female behaviors also undergo steroid-dependent organization during adolescence, and that social experience modulates steroid-dependent adolescent brain and behavioral development. The implications for human adolescent development are also discussed, especially with respect to how animal models can help to elucidate the factors underlying the association between pubertal timing and adult psychopathology in humans.
1959年，菲尼克斯、戈伊、杰拉尔和扬首次提出了激素驱动的大脑和行为性别差异的组织-激活假说。最初的假说认为，在发育早期接触类固醇激素会使神经回路男性化并消除女性化特征，从而设定成年期对激素的行为反应。这一假说激发了大量实验，证明围产期是对性腺类固醇激素最为敏感的时期。然而，我们实验室及其他机构最近的研究表明，依赖类固醇的行为组织也发生在青春期，这促使人们重新评估可能产生组织效应的发育时间框架。此外，我们提供的证据表明，青春期是男性交配行为依赖类固醇组织的一个单一的、漫长的产后敏感期的一部分，该敏感期从围产期开始，在青春期后期结束。这些发现与组织/激活假说的最初表述一致，但极大地扩展了我们对“早期”发育构成的认识。最后，我们提供的证据表明，女性行为在青春期也会经历依赖类固醇的组织过程，并且社会经历会调节依赖类固醇的青少年大脑和行为发育。我们还讨论了这些发现对人类青少年发育的影响，特别是动物模型如何有助于阐明人类青春期时间与成人精神病理学之间关联的潜在因素。
