Abnormal development of retinogeniculate X axons in strabismic cats: a possible substrate for visual dysfunction

Rearing cats with surgically induced esotropia results in a number of structural and functional abnormalities in the visual system. In the present experiments, we have studied the morphology of individual retinogeniculate X axons in esotropic cats using intracellular recording and staining techniques. After serially reconstructing stained axonal arbors, we find that some X axon terminations in A-laminae of the lateral geniculate nucleus (LGN) have larger volumes and lower bouton densities than normal. This is true for X axons projecting from both the deviated and the non-deviated eye. It is possible that these abnormalities in morphological development contribute to the disruptions in signal transfer that has been observed in X-cells in the LGN of esotropic cats.