The effects of fantastical pretend-play on the development of executive functions: An intervention study.

Although recent correlational studies have found a relationship between fantasy orientation (FO; i.e., a child's propensity to play in a fantastical realm) and higher order cognitive skills called executive functions (EFs), no work has addressed the causality and directionality of this relationship. The current study experimentally examined the directionality of the observed relationship between FO and EF development in preschool-aged children through an innovative play intervention employing a randomized controlled design. A sample of 110 children between the ages of 3 and 5years were randomly assigned to one of three conditions: fantastical pretend-play intervention, non-imaginative play intervention, or business-as-usual control. Results revealed that children who participated in a 5-week fantastical pretend-play intervention showed improvements in EFs, whereas children in the other two conditions did not. Within the fantastical pretend-play condition, children who were highly engaged in the play and those who were highly fantastical demonstrated the greatest gains in EFs. These data provide evidence for the equifinal relationship between fantasy-oriented play and EF development, such that engaging in fantasy-oriented play may be one of many ways to directly enhance EF development.

Acute withdrawal but not long-term withdrawal from methamphetamine affects sexual behavior in female rats.

The present study was designed to investigate the long-term effects of repeated methamphetamine (MA) exposure on sexual motivation in female rats tested after a period of drug abstinence. In Experiment 1, female subjects received three injections of MA (1.0mg/kg/day, every other day) or saline and were tested for paced mating behavior (where females could control the receipt of sexual stimulation from one male rat) 21 days after their last injection. In Experiment 2, female subjects received 12 consecutive injections of MA (1.0mg/kg/day) or saline and were tested for mate choice (where females could control the receipt of sexual stimulation from two male rats simultaneously) 6 days after their last injection. Experiment 3 was identical to Experiment 2 except that female subjects received no baseline mating test and were tested for mate choice 24h and 6 days after their last injection. Open field tests were conducted in each experiment to measure locomotor activity after repeated exposure to MA. Although repeated MA exposure increased locomotor activity, mating behavior was not facilitated after either a short (6 days) or long (21 days) period of drug abstinence. Nevertheless, sexual behavior was disrupted during the 24h acute withdrawal period. Therefore, although the present study found no evidence of cross-sensitization between female sexual behavior and MA after either a short or a long period of drug abstinence, sexual behavior in sexually naïve female rats is sensitive to the depressive state associated with acute withdrawal from MA. In conclusion, the results of the present study suggest that MA acts differently from other psychomotor stimulants, and that the effects of MA withdrawal on sexual behavior differ between male and female rats.