Hormonal and physical markers of puberty and their relationship to adolescent‐typical novelty‐directed behavior

Abstract

The extent to which characteristic adolescent behaviors are associated with pubertal changes or driven by more general, puberty-independent developmental alterations is largely unknown. Using physiological and hormonal markers of puberty, this experiment characterized pubertal timing across adolescence and examined the relationships among these variables and novelty-directed behaviors. Males and females were tested for response to novelty at P28, P32, P36, P40, P44, P48 and P75, and examined for balano-preputial skinfold separation and sperm presence (males) or vaginal opening (females), followed by blood collection for hormonal assessments. Despite earlier pubertal maturation in females, with maturation generally completed by P36 in females and P44 in males, novelty-directed behavior peaked at P32 and P36 in both sexes, and was unrelated to pubertal measures. These data support the suggestion that the ontogenetic peak in this behavior during adolescence is not notably puberty-dependent.

Eating high fat chow enhances the locomotor-stimulating effects of cocaine in adolescent and adult female rats

“…Conversely, low circulating concentrations of estradiol and progesterone (i.e., during the estrus stage of the cycle) are correlated with an increased behavioral response of female rats to cocaine (Roberts et al 1989). In the current study, eating high fat chow increased the effects of cocaine in adolescent rats that presumably were not sexually mature (Vetter-O'Hagen and Spear 2011), and in adult rats, that presumably were in different phases of the estrous cycle. Furthermore, in adult rats eating standard chow and tested repeatedly with drug, the effects of cocaine were stable over time.…”

Testosterone and estradiol differentially affect cell proliferation in the subventricular zone of young adult gonadectomized male and female rats

“…At this age, rats are in the prepuberal period and the level of testosterone (in males) is extremely low, while the level of estradiol (in females) is not increased as it will do in the following weeks (Vetter-O'Hagen and Spear, 2012). Gonadectomy after puberty may determine a sudden decrease from high to low estradiol or testosterone levels, whereas, at the prepuberty time the impact on the endocrine balance of individuals is less drastic.…”

Exciting fear in adolescence: Does pubertal development alter threat processing?

“…As we (Dahl, 2004; Forbes and Dahl, 2010) and others (Steinberg, 2008) have reviewed, the onset of adolescence is associated with an increased tendency to seek novel, high-arousal sensations, and this appears to be directly linked to pubertal maturation (though, see Vetter-O’Hagen and Spear, 2012, for evidence in rodents that novelty seeking is related to age not puberty). There is extensive evidence showing that pubertal increases in sensation seeking predict real-world risky behavior, such as smoking and sexual risk taking (Martin et al, 2002).…”