This is a condition where colour vision is normal but children cannot name colours even though they may be able to match them. Children with this condition can sort into different colours and may be able to consistently name black and white. This condition may be related to an impaired short term memory.

Further Information

http://nanonline.org/nandistance/mtbi/ClinNeuro/agnosia.html
http://www.maccs.mq.edu.au/~max/Vision