Es werden tierexperimentelle Befunde vorgestellt, die den Einfluss frühkindlicher Erfahrungs- und Lernprozesse auf die funktionelle Reifung des Gehirns und die zugrunde liegende neurobiologische Basis der Entwicklung geistiger und psychischer Fähigkeiten zeigen. Psychosoziale Einflüsse während Phasen früher postnataler Zeitfenster mit erhöhter neuronaler und synaptischer Plastizität können tiefgreifende dauerhafte Veränderungen der Hirnfunktionen induzieren, die sich später, nach Ablauf dieser plastischen Phasen, nur noch bedingt korrigieren lassen. Ein traumatisierendes frühes Umfeld kann zu einer Unter- bzw. Fehlentwicklung funktioneller Schaltkreise des Gehirns führen, wobei vor allem das limbische System betroffen ist, das für die höhere neuronale Integration von Kognition und Emotion wie auch für Lern- und Gedächtnisprozesse zuständig ist. Solche aus früher pathogener psychosozialer Erfahrung induzierten hirnbiologischen Fehlentwicklungen bilden wahrscheinlich die neurobiologische Grundlage von psychischen Störungen, die als Neurosen, Persönlichkeitsstörungen und affektive Störungen und somit als Erkrankungen klassifiziert werden, die bislang fast ausschließlich aus psychoanalytischer oder verhaltenstheoretischer, kaum aber aus hirnbiologischer Sicht betrachtet wurden. Implikationen für therapeutische Möglichkeiten und zukünftige Forschung werden diskutiert.
Juvenile Experience and Learning Modulate the Functional Maturation of the Brain: Relevance for the Genesis and Therapy of Mental Disorders
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.
Key words
Learning - Emotions limbic system - Brain development - Affective disorders
1 Die Arbeiten der Autoren werden gefördert durch den Sonderforschungsbereich 426 der Deutschen Forschungsgemeinschaft „Funktion und Dysfunktion des limbischen Systems”.
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1 Die Arbeiten der Autoren werden gefördert durch den Sonderforschungsbereich 426 der Deutschen Forschungsgemeinschaft „Funktion und Dysfunktion des limbischen Systems”.
