Abstract
One of the behavioral problems in present day pediatrics is a syndrome known as Minimal Brain Dysfunction (MBD). Despite many studies, little is known regarding the etiology, pathophysiology and neuropathology of this disorder. Hyperkinetic behavior is one of the most crucial disorders in MBD. With the experimental paradigms utilized to study hyperkinetic behavior, several animal models with similar symptomatology have been developed in recent years. In this review the author proposed two major methods inducing MBD-like syndrome: early electrical stimulation and neonatal hippocampal lesions. By these experimental treatments to the developing rat pups, several behavioral alterations which are strikingly similar to the MBD patients were obtained at different developmental stages. At the same time, our data could demonstrate the developmental retardation in synaptogenesis of the hippocampus in a group of rats which received electrical stimulation in early developmental stage as well as the functional compensation effects in a group of rats which received hippocampal damage in the neonatal stage. Thus, it was suggested that these morphological and/or functional changes might be related to the later physiological and/or behavioral disorders such as hyperkinetic behaviors and learning deficits in MBD.
