The first introduction to psychology normally comes in the form of biology classes. Many biology students already come into class with at least basic understanding of psychology. They understand that their genes determine how their bodies work, how they function and, to a certain degree, how they behave or what illnesses they might develop. But hardly any of these students have an understandable comprehension of what exactly DNA is, where it’s found in the body, why it causes problems, and how it can be manipulated or changed.
In the case of development, the genes passed from one generation to the next only need to survive. Genes are merely instructions for doing things. People, as all living things, are programmed through thousands of years of natural selection to participate in behavior that’s survival oriented. The basis for this programming is that the expression of specific genes that cause specific traits, such as aggressiveness, violence or sexuality. In the case of psychology, the genes that are passed on to us through our parents, siblings, or other kin will determine such behaviour.
In terms of understanding what is happening genetically, we’re still in the era of molecular biology. In this frame, genes are just packets of information carrying instructions. This is the way humans, plants and animals have been growing for centuries. However, in the last 50 years or so, a revolution in the field of psychology has occurred known as molecular biology or genomics. Genomics provides a new lens through which we can view the relationships between behavior and genes.
The molecular basis for human and behaviors memory is actually quite simple – it’s all about the epigenome. The Epigenome is a cellular memory storage which determines whether a behavior will be expressed or not. Like all memory storage systems, it contains information that is “programmed” in advance by the genome.
What we now know is that the genetic material that determines behavior exists in all of us, but in varying quantities. Most of the variations come from the variation in the copies of genes inside the cellular memory storage of the person. The copy of the gene that determines the behavior is called the epigome. It’s this specific copy that we call the epigenome.
The significance of the epigenome in psychology and its relationship to individual differences was shown in a landmark study on twins. For years, autism research was based upon research on twins. However, it was discovered that there was substantial heritability (hitability) to behavior which existed between individuals who had identical twins but whose traits were quite different. This study provided the first evidence of the significance of the epigenome in human behaviour and its link to abnormal behavioral disorders like autism.
Even though the importance of the Epigenome in psychology was established, many in the emotional field are reluctant to accept its potential as a substantial factor in mental illness. One reason for this is that it is difficult to define a real genetic sequence or locus that leads to a behavioral disorder. Another problem is that there are simply too many genetic differences between people to use a single DNA sequence to determine mental illness. Finally, although the research on the Epigenome has been promising, more work has to be done to determine the role that genetics play in complex diseases such as schizophrenia. If this finding holds true, it can be used as a basis for studying other complicated diseases that have complex genetic components.
If you are interested in knowing more about Epigenetics and how it applies to psychology, I highly recommend that you follow the links below. My site discusses the exciting new technologies that are available now to better understand how Epigenetics affects behavior and the susceptibility to disease. You can even hear me speak on my epigenetics and autism blog. My research into Epigenetics is centered on understanding the ecological causes of disease, but I also have been involved in analyzing the relationship between Epigenetics and Autism. My future posts will also talk about diseases of the brain which can be affected by Epigenetics.