[Carry-over of neurological disorders of infancy and childhood]

Carry-over implies following a patient from the age of childhood to the adulthood. In the developing brain, specific symptoms appear only after development of the neurons of the lesion site and those consisting of the downstream structures. Thus, in the basal ganglia disorders, those involving the striatal direct pathways and the descending output of the basal ganglia develop symptoms in childhood before 10 years old. However, those involving the indirect pathway and the ascending output appear later mostly in adulthood. The development of the brainstem aminergic neuron and the midbrain dopamine neuron are reflected in the sleep-wake rhythm and the pattern of the locomotion. Thus, the order and disorder of those aminergic neurons are evaluated by following the developmental maturation of these biological markers. Thus, carry-over is necessary for child neurology.