The first introduction to psychology usually comes in the kind 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 physically function and, to a certain extent, how they act or what illnesses they may develop. But very few of these students have an understandable understanding 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 have to survive. Genes are nothing more than instructions for doing things. People, as all living things, are programmed through thousands of years of natural selection to engage in behavior that is survival oriented. The foundation 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, grandparents, or other kin will determine such behavior.
In terms of understanding what is happening genetically, we’re still in the era of molecular biology. In this framework, genes are just packets of information carrying instructions. This is how 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 see the relationships between behaviour and genes.
The molecular basis for behaviors and human memory is in fact quite simple – it’s all about the epigenome. The Epigenome is a mobile memory storage that determines whether a behavior is going to 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. The majority 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 which determines the behavior is called the epigome. It is this specific copy that we call the epigenome.
The significance of the epigenome in psychology and its relationship to individual differences was revealed in a landmark study on twins. For years, autism research was based upon research on twins. However, it was found that there was substantial heritability (hitability) to behavior which existed between individuals who had identical twins but whose traits were very different. This study provided the first evidence of the significance of the epigenome in human behavior and its connection to abnormal behavioral disorders such as autism.
Although the importance of this Epigenome in psychology was established, many in the psychological area are reluctant to accept its potential as a significant element in mental illness. One reason for this is that it is hard to define a real genetic sequence or locus that leads to a behavioral disorder. Another problem is that there are just too many genetic differences between people to use a single DNA sequence to determine mental illness. Finally, although the study on the Epigenome has been promising, more work needs to be done to find out the role that genetics play in complex diseases such as schizophrenia. If this finding holds true, it may be used as a basis for studying other complicated diseases that have complex genetic components.
If you’re interested in knowing more about Epigenetics and how it applies to psychology, I strongly advise that you follow the links below. My site discusses the exciting new technologies that are available today to better understand how Epigenetics affects behavior and the susceptibility to disease. You can also hear me speak on my epigenetics and autism blog. My research into Epigenetics is focused on understanding the environmental causes of disease, but I have also been involved in studying the relationship between Epigenetics and Autism. My future articles will also discuss diseases of the brain which can be affected by Epigenetics.