Scott, E., & Panksepp, J. (2003). Rough-and-tumble play in human children. Aggressive Behavior, 29 (6), 539-551.

Abstract: Rough and tumble (R&T) play is a unique set of behaviors that can be reliably distinguished from aggression and other childhood activities. Although it may be the most fundamental form of play, it has received comparatively little experimental attention in the human species. Forty children, ages three to six, were allowed to play in pairs (10 male pairs, 10 female pairs) during a 30 minute videotaped session with no toys available while music played in the background during every other five-minute time period. The incidence frequency of children’s play and related behavioral activities were scored using 20 behavioral categories. The major findings show only modest gender differences in the frequency of play behaviors in such controlled social encounters; the main difference is that boys engaged in slightly more physical play solicitations than girls. Music facilitated General Motor Activities (e.g., Running and Walking behaviors), but not specific R&T play actions (e.g., Wrestling, Ventral and Dorsal contacts). Finally, most play behaviors as well as general activities declined systematically over the course of each recording session. This experiment highlights how human social play can be systematically studied in a controlled laboratory setting. (PsycINFO Database Record (c) 2004 APA, all rights reserved)(journal abstract)