Human behavioral sex differences: A role for gonadal hormones during early development?
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.
- SourceAvailable from: Rachel Wanjiku Njoroge[Show abstract] [Hide abstract]
ABSTRACT: The use of crude kerosene as a dietary supplement in boarding schools has been a common practice in east Africa and other countries for many years, with the belief of it reducing the sex drive (libido) at the pubertal stage. There is however no scientific basis for this belief. The present study aimed at using a rat animal model to investigate the effects of crude kerosene on serum testosterone levels, aggression and its possible toxic effects. Fifteen male albino rats of approximately similar age and average weights were put into three groups of five animals each; the control group (placebo), low kerosene dose (10 μl/day) group and high kerosene dose (300 μl/day) group. ELISA was used to determine the serum testosterone levels. During treatment, changes in aggression were observed and noted. Liver toxicity was determined using enzyme assays, total protein and albumin while renal toxicity was monitored using serum creatinine levels. A full hemogram was conducted to determine hematological effects. Various tissue biopsies were obtained and examined using histopathological techniques for evidence of toxicity. Contrary to the common belief, our findings showed an overall increase of serum testosterone levels of up to 66% in the low dose and 75% in the high dose groups, with an increasing trend by the end of the study. The high dose group showed significantly increased levels of white blood cells (WBC) (p = 0.036), red blood cells (RBC) (p = 0.025), hematocrit (HCT) (p = 0.03), red cell distribution width (p = 0.028) and platelets (p = 0.017). The histological results of the stomach indicated chronic gastritis.Toxicology Reports 12/2015; 2:175-183. DOI:10.1016/j.toxrep.2014.11.017
Dataset: GCE 2014 review
Dataset: GCE 2014 review