Part of Advances in Neural Information Processing Systems 10 (NIPS 1997)
The initial activity-independent formation of a topographic map in the retinotectal system has long been thought to rely on the matching of molecular cues expressed in gradients in the retina and the tectum. However, direct experimental evidence for the existence of such gradients has only emerged since 1995. The new data has provoked the discussion of a new set of models in the ex(cid:173) perimentalliterature. Here, the capabilities of these models are an(cid:173) alyzed, and the gradient shapes they predict in vivo are derived.