Play behavior: Testing a novel tool to study play in children and impact of acute corticosterone on play behavior

Abstract

Play is important for the development of non-human mammals and humans. Children that are in development benefit from play behavior to learn about social competence, solve complex problems and train their cognitive flexibility. Only, some children hamper with participating with play behavior. Pain, fatigue, social isolation and treatment of medicine may influence the participation of play in children with a chronic disease. To address whether children with a chronic disease have altered play behavior an ethogram to objectively measure play behavior was made. Furthermore, it is unknown if treatment of corticosteroids, which is a clinical used medicine, influences play behavior. Because two research questions were conducted, two different experiments were performed. In the first experiment, the goal was to improve the reliability of the ethogram which score different play behaviors in children. For this purpose, refinement of the description of the behaviors could increase reliability. Observers weekly scored children for 3 months to improve the domains described in the ethogram. Analyzes of the intra- and inter- observer reliability as well as the differences in frequency/sequence and frequency analyzes could support the refinement of the ethogram. Data showed that intra- and inter observer reliability was improved due to refinement of the ethogram. Nevertheless, the intra and inter reliability of frequency/sequence did not suffice the criteria of a reliability of 80%. In the second experiment, acute corticosterone was administered to rats to identify if corticosterone alters social play behavior. Corticosterone was administered in the rats in fashion of 0-, 3-, and 10 mg/kg. Rats were isolated for 2 hours before injection and 20 minutes after injection before putting paired rats in play cage. Play behavior was recorded and scored by the number of pounces and pins. Data analyzes using a one-way ANOVA showed no significant differences between groups treated with vehicle and with corticosteroids. Other social behaviors were also measured but did also not find any differences in treatment groups. Therefore, we observed no change in social play behavior after administration of corticosterone, suggesting that treatment with corticosterone does not alter the tendency of rats to engage in social play. These two experiments were conducted to reveal the challenges that children with a chronic cope with on a play behavior level.