Heredity, chromosomal disorders, birth complications, head injury, and a mother's alcoholism or drug abuse may be factors, but in most cases the cause is unknown. Medication may temporarily disguise neurodevelopmental problems, and standardized tests, especially IQ tests, do not detect many of the common and serious dysfunctions. Mental health professionals should be aware of a child' s neurodevelopmental status before undertaking psychotherapy. Although some of them have behavior problems as well, for most attention deficits comprise a significant learning disorder. They have trouble deciding what is relevant when they listen or read.
Many experience inordinate mental fatigue and are inattentive to details.
They often make careless errors and organize their work poorly. Writing is especially difficult for them, and many have associated memory problems. Certain children with otherwise intact cognitive capacities have serious memory deficiencies. Sometimes this deficit is confined to one processing modality, such as the visual, sequential, or verbal. Other students have difficulty maintaining several items at once in active working memory.