| Abstract: | The influence of deprivation procedures on the development of motion detection mechanisms has been studied in twenty-two kittens. Superior colliculus neurons did not acquire direction selectivity and normal ocular dominance in animals reared in the dark or in stroboscopic light; Neuron immaturity persisted in spite of a five week additional recovery period in normal conditions. Exposure to unidirectional visual motion for 10 h during the fifth week ofpostnatal age produced an asymmetric development of the two superior colliculi. Finally, unilateral neonatal ablation of visual cortex permanently impaired development of the ipsilateral superior colliculus. In the same or in different animals, development of optokinetic nystagmus, a typical visuomotor response, was similarly influenced by the global or selective deprivation procedures. These results suggest that motion detection mechanisms (both afferent and efferent) strongly depend upon constraints imposed by the visual world during the first weeks of life. |
