Grafting growth in the vascular cambium. Occasionally, a so-called "graft hybrid" or more accurately graft chimera can occur where the tissues of the stock continue to grow within the scion. Such a plant can produce flowers and foliage typical of both plants as well as shoots intermediate between the two. The best-known example this is probably +"Laburnocytisus" 'Adamii', a graft hybrid between "Laburnum" and "Cytisus", which originated in a nursery near Paris, France in 1825. This small tree bears yellow flowers typical of "Laburnum anagyroides", purple flowers typical of "Cytisus purpureus" and curious coppery-pink flowers that show characteristics of both "parents".
Colour centre the recognition of shapes, motion, and colour. V1 has multiple areas that are colour-sensitive, which indicates that colour processing is not limited to one area. According to a paper by Dr Robert Shapley, V1 has an important role in colour perception. fMRI experimental results showed that V1 has two kinds of colour sensitive neurons: single-opponent and double-opponent cells. These cells are integral in the opponent process of interpreting colour signals. Single-opponent neurons respond to large areas of colour. This is advantageous for recognizing large colour scenes and atmospheres. In comparison, double opponent cells respond to patterns, textures, and colour boundaries.