COLOR-BLINDNESS

The physiology of colour vision is discussed: as is the way in which t he human eye can detect various combinations of red, green and blue. R ed-green colour blindness, with X-linked inheritance, is the most comm on, but other types are also considered. Methods of testing relating t o the age of the child an reviewed. The use of colours in teaching is widespread, but there is controversy over the difficulties this may ca use a colour blind child. A review of the literature does not reveal m uch information on this, and any problems that do arise are likely to be individual to the child, and to depend on such factors as overall i ntelligence, the attitude of the teacher, and the personality of the c hild. There is no doubt that it is essential to recognise colour visio n defects when it comes to choosing a carter: and that tests must be d one during secondary schooling, but in order to avoid some affected ch ildren being disadvantaged there is enough evidence to support testing at school entry.