The effects of binocular and monocular occlusion on the number of optic nerve axons containing degenerative organelles.
In this study chicks were incubated in the dark and then reared for 2 days with either none, one or both eyes occluded. Cross-sections of the optic nerves were examined for profiles of axons containing accumulations of degenerative organelles. There were significantly more organelle-containing axons in the non-occluded and monocularly occluded birds compared with the binocularly occluded birds. There was no significant difference between the non-occluded and monocular group. Furthermore, there was no significant difference between the occluded and non-occluded eyes of monocular birds. We propose that the rise in organelle-containing axons during development reflects a phenomenon involved in the linking of the eyes, and that visual input to a single eye is sufficient to hasten this process.
D000818:Animals; D002645:Chickens / Q000033:anatomy & histology*; D008027:Light; D009900:Optic Nerve / Q000254:growth & development / Q000648:ultrastructure*; D009940:Organoids / Q000648:ultrastructure; D012683:Sensory Deprivation / Q000502:physiology*; D014785:Vision, Ocular / Q000502:physiology