Top. Ferret LGN 2 days (P2), 10 days (P10) and 25 days (P25) after birth. Eye segregation is completed at P10 and ON-OFF segregation is completed at P25. A, C, C2: contralateral layers, A1, C1: ipsilateral layers. C3: layer not receiving retinal input, OT: optic tract, MIN: medial interlaminar nucleus, vLGN: ventral lateral geniculate nucleus, W: wing of the geniculate, on: on layers, off: off layers. Reproduced from (Speer et al 2010). Bottom. Cartoon illustrating the stages of retinal afferent segregation in LGN, first by eye and later by ON-OFF contrast polarity (based on (Speer et al 2010)).