SPATIAL-LEARNING AND MEMORY DEFICITS AFTER TELENCEPHALIC ABLATION IN GOLDFISH TRAINED IN-PLACE AND TURN MAZE PROCEDURES

The present work investigated whether the fish telencephalon is involv ed in spatial learning based on place strategies in a manner similar t o mammalian hippocampus. Goldfish were trained in a 4-arm maze in a ro om with relevant spatial cues. Sham and to-be-ablated subjects were tr ained in each of 4 experimental procedures designed as follows: place, turn, place-turn, and control. After acquisition, complete ablations of both telencephalic hemispheres for the experimental groups were car ried out. The results showed that ablation exclusively impaired perfor mance in animals using place strategies; in these, accuracy fell to ch ance level during both postsurgery retraining and reversal periods. In the other groups, ablation of the telencephalon did not induce any si gnificant deficit. These results suggest that the fish telencephalon p lays a crucial role in complex place learning.