Facing colour engineers and support corps normally had a single branch colour, although exceptionally each regiment of Swedish artillery had its own facing colour until 1910. The United States regular army after the American Civil War adopted a universal dark and light blue uniform under which each regiment was distinguished only by numbers and other insignia, plus branch colors. The latter were yellow for Cavalry, red for Artillery and white (later light blue) for infantry. Combinations of colors such as scarlet piped with white for Engineers, orange piped with white for the Signal Corps and black piped with scarlet for Ordnance personnel
Colour centre ventral occipital area plays an important role in colour vision. The search for the human equivalent of V4 led to the discovery of other areas that were stimulated by colour. The most significant was an area anterior in the ventral occipital lobe, subsequently named V4α. Further fMRI experiments found that V4α had a different function than V4, but worked cooperatively with it. V4α is involved in a number of processes, and is active during tasks requiring colour ordering, imagery, knowledge about colour, colour illusions, and object colour. The V4 and V4α areas are separate entities, but because of their close