The reason why kids confuse letters such as 'b' with 'd' - mirror images - while learning how to write has been revealed in a new study.
Stanislas Dehaene of INSERM, the National Institute of Health and Medical Research in Saclay, France, says that the phenomenon occurs because of children "recycling" an area of the brain that recognises shapes and patterns.
Dehaene suggests that at birth, the VWFA (visual word form area) responds to all visual information in both the normal and the mirror orientation.
But as we learn to read and write, it is "recycled" - it "unlearns" the mirror form of words and letters, so that by adulthood it no longer responds to them.
"It's no wonder that children have so many difficulties with mirror reading and writing," says Dehaene.
"They are trying to learn to read with precisely the area of the brain that has the most sensitivity to recognising mirror images."