Early postnatal development of functional ocular dominance columns in cat primary visual cortexRathjen, Stefan1,2; Löwel, Siegrid1,3Neuroreport: 3 August 2000 - Volume 11 - Issue 11 - p 2363–2367 Vision, Central Abstract Author Information During postnatal development of the visual cortex the thalamocortical afferents serving the two eyes segregate into alternating patches called ocular dominance (OD) columns. Interested in the dynamics of this segregation process we studied the appearance of functional OD columns in the primary visual cortex of normally raised and strabismic kittens aged 2–6 weeks using 2-deoxyglucose labelling in awake animals. In both experimental groups, OD columns covering the entire area 17 and spanning all cortical laminae are first visible at 3 weeks and appear already adult-like at 4 weeks, much earlier than thought on the basis of previous anatomical studies. We hypothesize that a small and anatomically undetectable imbalance between the afferents from the two eyes is amplified by intracortical interactions so that their activity patterns become different and may guide the segregation process of the afferents in cortical layer IV. 1Leibniz-Institut für Neurobiologie, Brenneckestr. 6, D-39118 Magdeburg 2Max-Planck-Institut für Hirnforschung, Deutschordenstr. 46, D-60528 Frankfurt am Main, Germany 3Corresponding Author: Siegrid Löwel Received 26 April 2000; accepted 10 May 2000 © 2000 Lippincott Williams & Wilkins, Inc.