Social play in juvenile rats: a decade of methodological and experimental research.

The social play behavior of juvenile rats was originally described nearly a century ago, but research methods have only recently included the controlled laboratory investigation of psychobiological variables. This review covers the experimental literature of social play or play fighting behavior in juvenile laboratory rats reported during the last decade. Innovative measures for quantifying social play are described; hormonal, pharmacological, and neurological variables are examined; and interpretative concepts of social play are discussed. The current emphasis on measures and procedures as well as the limited scope of current research effort suggests a formative stage of research development.