Research has found that environmental factors can actually change the physical structure of the brain (Lenroot and Giedd, 2008). The mental state of an animal can be responsible for the release or suppression of a chemical, which can influence gene expression. Environmental influences, the presence of certain chemicals and the release of hormones and neurotransmitters can modify gene expression. Gene expression can be modified without changing the underlying DNA. There are certain areas that have been identified as “switch” DNA which previously was thought to be "junk" DNA. However, the more we research the area the more we realize how important this "non-coding" DNA is. The switches do not directly lead to the synthesis of proteins. However, switches and homeobox genes, which control switches, tell the protein-synthesizing DNA when to turn on and turn off and how "intense" the synthesis should be.
Genes affect people’s behavior and experience, but their experiences and behavior also affect gene expression (Gottlieb, 2003; Rutter 2006). This bidirectional relationship between heredity and environment is known as the epigenetic framework (Gottlieb). Development takes place through ongoing, bidirectional exchanges between heredity and all levels of the environment.
The Center on the Developing Child at Harvard University have been exploring how early experiences can alter gene expression and affect long-term development. They explain that “the approximately 23,000 genes that children inherit from their parents” form what they call a “structural genome” (Shonkoff et al., 2010, p.1). This structural genome is compared to the hardware of a computer because it determines the boundaries of what’s possible, but does not work without an operating system to tell it what to do. In the genome, the operating system is called the “epigenome” and it determines which functions the genetic “hardware” does and does not perform (Shonkoff et al., 2010). Through time, positive experiences, such as rich learning opportunities, or negative influences, such as “environmental toxins” or stressful life circumstances, leave a chemical “signature” on the genes. These signatures can either temporarily or permanently affect how easily the genes are switched on or off. These experience-driven, chemical changes can play particularly key roles in brain and behavioral development (Shonkoff et al., 2010).
Laura Berk, a leading psychologist on child development, explains that providing a baby with a healthy environment and diet increases brain growth, leading to new connections between nerve cells which influence gene expression. This allows for new “gene-environment exchanges” such as advanced exploration of objects and interaction with caregivers (Berk, 2010). This helps to further enhance brain growth and gene expression. Supportive environments and rich learning experiences generate positive epigenetic signatures that “activate” genetic potential. The stimulation that occurs in the brain through active use of learning and memory circuits can establish a foundation for more effective learning capacities in the future because it is rooted to these epigenetic changes (Shonkoff et al., 2009).
In contrast, harmful environments can dampen gene expression. At times, National Scientific Council explains, “the effect can be so profound that later experiences can do little to change certain characteristics that were initially flexible” (Shonkoff et al., 2010). Epigenetic changes can be caused by repetitive, highly stressful experiences that can damage the systems that manage one’s response to adversity later in life (Szyf, 2009). For some, this epigenome provides a molecular level explanation for why and how early experiences, whether positive or negative, can have an impact that last for life.
Effective interventions can literally alter how children’s genes work and thereby have long-lasting effects on their mental and physical health, learning and behavior. In this respect, “the epigenome is the crucial link between the external environments that shape our experiences and the genes that guide our development” (Shonkoff, 2010, p.2). Gaining a greater understanding of the environmental factors that influence the development of our brains and behavior will allow us to more effectively create policy to provide a healthy environment for developing children.
Since environmental factors can change how the components of the brain exchange information and interact, it must be accounted for in a systems analysis. This external influence of the environment makes it difficult to define clear boundaries for the system; this property is characteristic of complex, open systems.
Genes affect people’s behavior and experience, but their experiences and behavior also affect gene expression (Gottlieb, 2003; Rutter 2006). This bidirectional relationship between heredity and environment is known as the epigenetic framework (Gottlieb). Development takes place through ongoing, bidirectional exchanges between heredity and all levels of the environment.
The Center on the Developing Child at Harvard University have been exploring how early experiences can alter gene expression and affect long-term development. They explain that “the approximately 23,000 genes that children inherit from their parents” form what they call a “structural genome” (Shonkoff et al., 2010, p.1). This structural genome is compared to the hardware of a computer because it determines the boundaries of what’s possible, but does not work without an operating system to tell it what to do. In the genome, the operating system is called the “epigenome” and it determines which functions the genetic “hardware” does and does not perform (Shonkoff et al., 2010). Through time, positive experiences, such as rich learning opportunities, or negative influences, such as “environmental toxins” or stressful life circumstances, leave a chemical “signature” on the genes. These signatures can either temporarily or permanently affect how easily the genes are switched on or off. These experience-driven, chemical changes can play particularly key roles in brain and behavioral development (Shonkoff et al., 2010).
Laura Berk, a leading psychologist on child development, explains that providing a baby with a healthy environment and diet increases brain growth, leading to new connections between nerve cells which influence gene expression. This allows for new “gene-environment exchanges” such as advanced exploration of objects and interaction with caregivers (Berk, 2010). This helps to further enhance brain growth and gene expression. Supportive environments and rich learning experiences generate positive epigenetic signatures that “activate” genetic potential. The stimulation that occurs in the brain through active use of learning and memory circuits can establish a foundation for more effective learning capacities in the future because it is rooted to these epigenetic changes (Shonkoff et al., 2009).
In contrast, harmful environments can dampen gene expression. At times, National Scientific Council explains, “the effect can be so profound that later experiences can do little to change certain characteristics that were initially flexible” (Shonkoff et al., 2010). Epigenetic changes can be caused by repetitive, highly stressful experiences that can damage the systems that manage one’s response to adversity later in life (Szyf, 2009). For some, this epigenome provides a molecular level explanation for why and how early experiences, whether positive or negative, can have an impact that last for life.
Effective interventions can literally alter how children’s genes work and thereby have long-lasting effects on their mental and physical health, learning and behavior. In this respect, “the epigenome is the crucial link between the external environments that shape our experiences and the genes that guide our development” (Shonkoff, 2010, p.2). Gaining a greater understanding of the environmental factors that influence the development of our brains and behavior will allow us to more effectively create policy to provide a healthy environment for developing children.
Since environmental factors can change how the components of the brain exchange information and interact, it must be accounted for in a systems analysis. This external influence of the environment makes it difficult to define clear boundaries for the system; this property is characteristic of complex, open systems.
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