[The contribution of neuropsychology to the diagnosis and treatment of learning disorders].
In its broadest sense, the basic concept of Neuropsychology is that all behaviour originates in the brain; according to Luria, it depends on functional systems constituted by different areas of the brain which are inter related. Each area deals with a particular function which is part of the whole (for example, the cortical area for vision deals with reading). Which cortical areas make up the functional system depends on how the person acquired a certain type of behaviour. The neuropsychological model, when applied to learning disorders, assumes that they are the expression of specific cerebral dysfunction due to genetic or environmental factors which have altered the development of the nervous system. Pennington recognizes five functional systems or nodules related to intellectual function. Each of these corresponds to a clearly defined zone of the cerebrum and impaired function of any zone causes specific learning disorders. Thus, the left perisylvan region deals with neurolinguistic function and disorders of this causes dyslexia. The hippocampal area of both hemispheres is related to memory and changes in this lead to disorders of memory. Right hemisphere dysfunction causes dyscalculia (posterior right hemisphere) and behaviour disorders (anterior right hemisphere) which may present together or separately. The dysexecutive syndrome is due to frontal lobe changes and is characterized by attention deficit, poor planning and anticipation, defective abstraction and other behaviour disorders. Although these are the best defined and most commonly seen syndromes in clinical practice, it would be logical to expect that there may be as many types of disorder as there are neural systems or subsystems involved in particular types of learning or behaviour, which may be altered. In support of these concepts we report four clinical cases seen by us in the Italian Hospital, Buenos Aires.