The role of binocular neurons in the cat striate cortex in combining information from the two eyes.

Cats were raised under conditions of daily alternating monocular exposure, so that each eye received normal input, but the animals were never allowed to use both eyes simultaneously. With single cell recording techniques it could be shown that this led to a severe disturbance of the normal binocularity of cortical neurons. The cats were trained by operant techniques in a two-choice box to discriminate with each eye non-retinotopic stimulus pairs. To test the ability to combine binocular signals it was tested whether the learned discrimination would transfer to red/green colored stimuli which were viewed dichoptically through appropriately colored contract lenses. The arrangement was such that the positive stimulus could be distinguished from the negative stimuli only when the signals from both eyes were combined and used simultaneously. All cats showed immediate transfer, from the monocularly learned discrimination task to the dichoptic paradigm. This indicates that the presence of a normal population of binocular cortical cells in area 17 is not a prerequisite for the ability to use binocular cues for the solution of a pattern discrimination task.