Postnatal Development of the Visual Cortex and the Influence of Environment.

摘要: In the early sixties, having begun to describe physiology of ceils in adult cat visual cor tex (1), David Hubel and I decided invest igate how highly specific response properties cort ical cells emerged during postnatal development. We were also interested e x a m i n g rote experience normal development, ques t ion ra sed d iscussed by philosophers since ime Descartes . The design these experiments was undoubtedly influenced observation that children with congenital ca ta rac s still have substantial often permanent deficits af ter removal proper refract (2). Also, behavioral studies had shown animals raised dark or an environment devoid contours similar impairment their functions (3,4). Because difficulties associated raising kittens total da rkness , we fuse lids suture. This procedure p r v any fo rm vision wi thout completely light-depriving imal c this be f fec ive because respond are insensitive changes levels diffuse light (5) Initially only one eye closed, using other as control. turned out for tunate below single lo u re on more dramatic than results obtained from both eyes occluded kept dark. Our initial findings lid suture first three months life blind deprived eye, ia te majority responded stimulation (6). defect appeared localized cortex, perhaps at site interact between geniculate afferents cortical (7) From another series experiments, found orientat specif ic ty binocularity developed through innate mechanisms (8) result, taken together monocular deprivation experiment, nd ica ed neural connections present can modified experience. Such plasticity not observed but existed (9). done cat, soon our tent rhesus macaque monkey. After demons ted monkey select ively lines different orientations binocular (10),