Article

Collaer ML, Hines M. Human behavioral sex differences: a role for gonadal hormones during early development? Psychol Bull 118: 55-107

Department of Psychology, University of California, Los Angeles, USA.
Psychological Bulletin (Impact Factor: 14.39). 08/1995; 118(1):55-107. DOI: 10.1037/0033-2909.118.1.55
Source: PubMed

ABSTRACT Evidence that gonadal hormones during prenatal and neonatal development influence behavior is reviewed. Several theoretical models of hormonal influences, derived from research in other species, are described. These models are evaluated on the basis of data from humans with either normal or abnormal hormonal exposure. It is concluded that the evidence is insufficient to determine which model best explains the data. Sexual differentiation may involve several dimensions, and different models may apply to different behaviors. Gonadal hormones appear to influence development of some human behaviors that show sex differences. The evidence is strongest for childhood play behavior and is relatively strong for sexual orientation and tendencies toward aggression. Also, high levels of hormones do not enhance intelligence, although a minimum level may be needed for optimal development of some cognitive processes. Directions for future research are proposed.

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    • "The process of puberty results in the release of some specific hormones which are primarily responsible for the development of secondary sex characteristics and for the emergence of reproductive capabilities in boys [2]. During this stage an increase in testosterone causes an increase in the sex drive (libido), enlargement of the reproductive organs such as the penis and testes, the production of sperm, increase of muscle mass and lowering of the voice, increased frequency of erection, and the growth of facial, chest, nipple and pubic hair among boys [3]. "
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    • "Deleterious mutations in AR can result in syndromes ranging from mild abnormalities to total failure of normal male phenotypic development (McPhaul, 2002a,b). AR also has associations with disease states (such as prostate cancer) and behavior in humans (Collaer and Hines, 1995; Wyce et al., 2010; Zitzmann and Nieschlag, 2003). Androgen receptors (AR) are DNA-binding transcription factors, the main regulators of androgen signaling in the cell, activated mostly by testosterone and 5α-dihydrotestosterone. "
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    • "A second NIH-sponsored report published in 2007, the Chapel Hill Consensus Statement, indicated that extensive data in rodents identified the potential for adverse outcomes in humans due to exposure during critical periods of development, and that the changes would likely be irreversible (vom Saal et al., 2007). Ethical considerations, however, make any study of potential vulnerabilities in children to BPA limited to epidemiological approaches that reveal correlations but not causation (Collaer and Hines, 1995; Rochester, 2013; Trasande et al., 2012). Another environmental estrogen that is prevalent globally is 17a-ethinyl estradiol (EE2), the active estrogen in birth control pills (Caldwell et al., 2012; Hinteman et al., 2006; Kostich et al., 2013; Lu et al., 2011; Pojana et al., 2004; Zhou et al., 2012). "
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