“Early experiences leave chemical “Signatures” on genes- The brain is particularly responsive to experiences and environments during early development. The physiological activity created by experience is powerful in shaping brain architecture and actually changes the chemistry that encodes the genes in brain cells. External Experiences spark signals between neurons, and the cells respond by producing proteins. These Gene Regulatory Proteins head to the cell nucleus, where they either attract or repel enzymes that can attach them to the genes. Positive experiences, such as exposure to rich learning opportunities, and negative influences, such as malnutrition or environmental toxins, leave a chemical “signature” on the genes, which can be temporary or permanent. This process is called epigenetic modification”. Excerpt from Harvard Health.
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