Resurgence in Siamese fighting fish, Betta splendens.

Resurgence of previously reinforced responding was investigated in male Siamese fighting fish (Betta splendens). Swimming through a ring produced 15-s mirror presentations according to, with different fish, either a fixed-ratio 1 or a variable-interval 60-s schedule of reinforcement. When responding was stable, a differential-reinforcement-of-other-behavior schedule was substituted for the mirror-presentation schedule. Following this, mirror presentations were discontinued (extinction). During this latter phase, there were transient increases in the ring-swim response relative to the frequency of such responding during the differential-reinforcement-of-other behavior schedule. Resurgence was similar for the fish exposed previously to the fixed-ratio or to the variable-interval schedule. These results extend to Siamese fighting fish a well-established behavioral phenomenon previously not observed in this species or with this response topography, and only rarely reported following the removal of a non-consumable reinforcer.