Many children today are reported to have attention deficit disorders.
There is much in the literature about attention and vigilance disorders in children. These are usually focused on physically based problems (ADD).
By and large they deal with the problems that a child may have in focusing on a particular figure.
If a child can't find the figure, the problem could be a with figure-ground discrimination (focus). We have discussed this in the topics of visual and auditory perception.
They frequently have problems with sustained focus. This involves memory motivation and arousal. We will be discussing arousal shortly.