Human and preclinical models of addiction demonstrate that gonadal hormones modulate acquisition of drug seeking. Little is known, however, about the effects of these hormones on extinction of drug-seeking behavior. Here, we investigated how 17ß-estradiol (E[subscript 2]) affects expression and extinction of cocaine seeking in female rats. Using a…

The present study used within-session transitions between two concurrent schedules to evaluate choice in transition. Eight female Long-Evans rats were trained to respond under concurrent schedules of reinforcement during experimental sessions that lasted 22 hr. The generalized matching equation was used to model steady-state behavior at the end of…

Operant conditioning with "Betta splendens" ("Bettas") has been investigated extensively using males of the species. Ethological studies of female "Bettas" have revealed aggressive interactions that qualitatively parallel those between male "Bettas". Given these similarities, four experiments were conducted with female "Bettas" to examine the…

This article presents an analysis of the longitudinal consequences of out-of-school science learning with a conceptual framework that connects the intentions of youth to their participation in science. The focus is on one girl's science activities in her home and hobby pursuits from fourth to seventh grade to create an empirical account of how…

In many nonhuman species of vertebrates, females are attracted to red on male conspecifics. Red is also a signal of male status in many nonhuman vertebrate species, and females show a mating preference for high-status males. These red-attraction and red-status links have been found even when red is displayed on males artificially. In the present…