The effects of social deprivation on levels of social play in the laboratory rat Rattus norvegicus.

Previous studies on a variety of species suggest the existence of a 'rebound' effect in social play: young animals may show heightened levels of play, following temporary deprivation of opportunity for social interaction. The present experiment investigated this phenomenon in greater detail, by measuring the effect of different types of social deprivation on levels of social play in prepubescent laboratory rats Rattus norvegicus. In one deprivation condition, subjects were denied whole-body contact, but not other forms of social interaction; in another condition, subjects experienced more extensive isolation. Both kinds of deprivation produced equally large post-deprivation increases in social play, suggesting that the important factor in producing the rebound effect is the absence of opportunity for whole-body contact - the predominant component of "rough and tumble" social play.