Juvenile experience and learning modulate the functional maturation of the brain: relevance for the genesis and therapy of mental disorders

Abstract

This article summarizes experimental data that indicate how juvenile experience and learning events modulate the functional maturation of the brain, shaping thereby the neuronal substrate for the development of intellectual and socio-emotional abilities. The fact that early experience occurs during early postnatal brain development, i.e. phases of elevated neuronal and synaptic plasticity, results in an "imprinting" of synaptic connectivity and neural circuitry in the infant brain. Results from experimental research in animal models support the hypothesis that impoverished intellectual stimulation and disturbance of the socio-emotional environment during early childhood may disturb the formation of functional brain pathways, in particular of the limbic circuits, which play a major role in emotion and learning. Such defective brain systems, representing neurofunctional "scars" in the brain, may be the neuronal basis of a variety of mental disorders and clinical symptoms caused by early stressful psychosocial environment. Ultimately, the goal will be to apply the knowledge gained to the development of biological and psychosocial intervention strategies by utilizing remaining plasticity of the adult human brain aimed at promoting human health, decreasing susceptibility and increasing resistance to disease.