Interocular transfer of visual discriminations in goldfish after selective commissure lesions.

Goldfish with transections of the intertectal commissure learned but failed to transfer interocularly a simple visually cued avoidance task in a shuttle box, whereas posterior commissure lesions had no effect on this simple transfer task. However, fish with tectal commissure lesions could show normal interocular transfer of a shape discrimination, once discrimination pretraining with color cues had been carried out with each eye separately. Lesions of anterior commissure had no effect on either shape or color transfer, but fish with intended cuts of the postoptic commissures showed striking deficits of interocular transfer. As with comparable studies in the pigeon, it is concluded that postoptic, but not tectal, commissures are required for interocular transfer in the goldfish.