DEVELOPMENT OF IDENTICAL ORIENTATION MAPS FOR 2 EYES WITHOUT COMMON VISUAL EXPERIENCE

IN the mammalian visual cortex, many neurons are driven binocularly an d response properties such as orientation preference or spatial freque ncy tuning are virtually identical for the two eyes(1). A precise matc h of orientation is essential in order to detect disparity and is ther efore a prerequisite for stereoscopic vision. It is not clear whether this match is accomplished by activity-dependent mechanisms together w it the common visual experience normally received by the eyes(2,3), or whether the visual system relies on other, perhaps even innate, cues to achieve this task(4-7). Here we test whether visual experience is r esponsible for the match in a reverse-suturing experiment in which kit tens were raised so that both eyes were never able to see at the same time. A comparison of the layout of the two maps formed under these co nditions showed them to be virtually identical. Considering that the t wo eyes never had common visual experience, this indicates that correl ated visual input is not required for the alignment of orientation pre ference maps.