Abstract
Tested 24 male, Long-Evans hooded rats in 2 motivational states (hungry and satiated) and 2 social conditions (single and paired) in adjacent and communicating Skinner boxes for the effect of a social stimulus on operant behavior. The social stimulus interfered in all conditions except 1: satiated Ss paired with hungry Ss pressed the bar significantly more often than in any other condition. It is concluded that the social facilitation effect is produced by progressive changes in the motivational state of the S as well as by a set of stimuli triggering the operant behavior. (PsycINFO Database Record (c) 2006 APA, all rights reserved)