Autoshaping and paleostriatal lesions in the pigeon

Three experiments were conducted with the pigeon (Columbia livia) to investigate the effects of bilateral electrolytic lesions of the paleostriatum on classical conditioning paradigms. In Experiment 1 naive subjects were given autoshaping training to a white centre key light and it was found that paleostriatal pigeons showed higher peck rates than unoperated controls. A further group of naive paleostriatal pigeons showed higher rates of autoshaped responding but did not differ from controls on a successive autoshaping discrimination with colour (Experiment 2A) or striped (Experiment 2B) stimuli. In Experiment 3 paleostriatal pigeons performed better than controls on a go, no-go alternation. The higher response rates shown by paleostriatal pigeons during autoshaping could not readily be explained in terms of a (non-associative) motor disturbance such as a tremor which could have caused multiple key pecks to be emitted in view of the demonstrations of unimpaired discrimination (Experiment 2) and better alternation (Experiment 3). Instead, the results suggest that paleostriatal pigeons may show potentiated classical conditioning.