Fig. 5.

Speed of acquisition and lateralization of NCM. A: learning curves, showing the latency to reach behavioral criterion (80%) on the first discrimination, in examples from a fast and a slow learner. B: in NCM, fast learners showed stronger ARMs in the left hemisphere compared with the right (P < 0.001, KS test) for all stimuli. This asymmetry is the opposite from what has been reported in naive birds (Phan and Vicario 2010). In contrast, slow learners were not significantly lateralized. Lateral differences were not seen in CMM recordings.